Final Report Summary - DIAGNO-RAIL (Combining innovative portable VISUAL, ACOUSTIC, MAGNETIC, and NMR methods, with in-situ CHEMICAL diagnostic tools for effective failure assessment and maintenance strategy of RAIL and subway systems)
Executive Summary:
Railways are one of the prime modes of transportation in European Union and as they are closely associated with intensive passenger and cargo transportation, they own high risk in terms of potential loss of human life and damage/destruction of assets. New technologies and stringent safety standards are constantly being introduced, to reduce risks associated with derailments and collisions. A detailed assessment of the defects which emerge both in the rolling stock and the rail infrastructure is essential to apply the correct maintenance strategy. At the same time large span or segmental bridges and tunnels, which are important parts of rail systems are particularly susceptible to deterioration with increasing risk of failure due to often-harsh and aggressive environments, in combination with aging and increasing traffic load. Evidently, efficient maintenance strategies of complex rail systems, which are based on fast and reliable inspection methods, can reduce significantly potential risks and cost. The overall aim of the project is to develop an integrated system of state-of-the-art NDT methodologies to improve risk assessment and failure prediction concerning the integrity and functionality of rail systems, in favour of the participating SMEs. In particular precise Visual and Magnetic ac-Susceptibility methods, for fast and reliable assessment of track failure and damage will be combined with state-of-the-art Acoustic, and Nuclear Magnetic Resonance (NMR) portable devices appropriate for examining the performance of concrete structures, in order to gain critical information concerning the performance, damage risk, and condition monitoring of rail and subway systems. In parallel an innovative chemical tool kit will be developed for in-situ chemical analysis measurements, which in combination with modern established analytical techniques will be used to characterize in-situ materials.
Project Context and Objectives:
Railways are one of the prime modes of transportation in European Union and as they are closely associated with intensive passenger and cargo transportation, they own high risk in terms of potential loss of human life and damage/destruction of assets. New technologies and stringent
safety standards are constantly being introduced, to reduce risks associated with derailments and collisions. A detailed assessment of the defects, which emerge both in the rolling stock and the rail infrastructure, is essential to apply the correct maintenance strategy.
Some of the rail degradations include worn out rails, weld problems, internal defects, corrugations and rolling contact fatigue (RCF) initiated problems such as surface cracks, head checks, squats, chipping and shelling. On the other hand, the attachments between rail and sleepers could be damaged, broken or missing, the quality of the ballast deteriorated. If undetected and/or untreated, these defects can lead to rail breaks and derailments.
The consequences of derailment in terms of loss of human life, damage/destruction of assets and loss of company trust and reputation justify maintaining stringent safety standards, which require massive rail maintenance investments in order to be met. Reduction in maintenance investments may increase the rate of rail degradation, which may increase the risk of derailments.
At the same time large span or segmental bridges and tunnels, which are important parts of rail systems are particularly susceptible to deterioration with increasing risk of failure due to often harsh and aggressive environments, in combination with aging and increasing traffic load.
Evidently, efficient risk management and maintenance strategies of complex rail systems, which are based on fast and reliable inspection methods, can reduce significantly potential risks and cost. In Europe and other developed parts of the world, there are a lot of SMEs working with modern
technologies in the field of Non Destructive Monitoring of the performance of rail infrastructures. In spite of continuous efforts made by all rail organizations and relevant Non-Destructive-Testing (NDT) companies, detailed knowledge of methodologies and testing techniques has not kept pace with the development, as in both cases engineers have struggled to keep abreast with the increasing complexity of the applied methodologies. Because of this, testing quality and interpretation of results have suffered, compounded on occasion by insufficient knowledge of such specialized techniques by both applicants and supervisors of works. Even more, appropriate advice for necessary maintenance actions is not readily available being spread amongst many different specifications and references some of which outdated.
The overall aim of DIAGNO-RAIL is to develop an integrated system of state-of-the-art NDT methodologies based on multiple expertises improving risk assessment and failure prediction concerning the integrity and functionality of main track components and rail infrastructures in favour of the participating SMEs.
In particular precise Visual and advanced Magnetic Detection methods, for fast and reliable assessment of track failure and damage will be combined with state-of-the-art Acoustic methods, and Nuclear Magnetic Resonance (NMR) portable devices appropriate for examining the performance of concrete structures, in order to gain critical information concerning the performance, damage risk, and condition monitoring of rail and subway systems. In parallel,
advanced methodologies such as infrared thermography, and half cell potential will be applied, while an innovative chemical tool kit will be developed for in situ chemical analysis measurements, in combination with established modern analytical techniques, for civil construction materials characterization.
In the above framework the following S&T objectives have been set:
(i) The development of a set of methodologies for monitoring integrity, damage, and failure of track components.
Specifically:
1. A system of high definition camera fixed on a rolling vehicle associated with a high speed acquisition system and fitted floodlighting for complete image monitoring of the track is implemented. The image monitoring will be continuous up to the speed of 70km/h. The determination of optimum conditions for reliable continuous image monitoring of the track up to the speed of 70 km/h and a set of at least 10 000 reliable images is a measure for the meeting of the
objective.
In particular, an autonomous imaging hardware including high-speed high-definition camera with synchronized lighting and high-speed, high-capacity image acquisition and storage system developed by Alcon Diaz Consulting. This device can be embedded in any railway vehicle providing 500 W, 230 V AC supply. It provides continuous image monitoring of the track with inspection speed up to 70 km/h. More than 90 000 images were acquired during the project and more than 13 km of railway track were successfully inspected during real-scale field tests.
2. A fast image processing software will be developed and used for rail integrity verification, rail geometry measurements, switches and crossings location and condition, rail attachments monitoring, sleepers condition, ballast quality control, dilatation joints displacement measurements.
The measures of the successful completion of this objective include:
- identifying and localising principal components of the track (switches, crossings, dilatation joints, signalisation equipments); characterizing the geometry of the rail;
- measuring displacements of dilatation joints concurrently with temperature measurements of the rail;
- identifying the rail-sleeper attachments and sleepers condition;
- characterizing the mean size of the ballast aggregates.
In particular, an extended image processing software developed by the University of Cergy-Pontoise including various functionalities. Its first function is the generation of panoramic reconstruction of the track by stitching the series of successive images of the track acquired by the autonomous imaging hardware. Panoramic reconstruction of the track is the essential tool for safe, accurate and economic visual inspection and control of the state of the main components and devices of the track. Using processes of forms recognition, customized algorithms, specific criteria and thresholds, the image processing software includes additional functions with the aim of controlling the whole railway track, identifying critical defects and providing hard core information for risk management and maintenance strategy to the railway companies. These additional functions concern the automatic identification of sleepers on panoramic images, the automatic measure of the distance between adjacent sleepers, the automatic identification of the presence or the missing of bolts and screws and the measure of the aperture of thermal expansion devices.
3. A novel method for the magnetic detection of cracks in rail tracks based on the measurement of the magnetic induction of the surface of rails, by an appropriate array of magnetic field sensors (magnetic detection device).
The measure of the meeting of the objective includes complementary NDT methodologies such as Eddy Current and Ultrasonic methods which will be used to test the reliability of the proposed methodology.
4. Appropriate software for the magnetic detection device. The measures for the successful completion of the objective include:
- The software must communicate with the array of the magnetic sensors
- The software must be able to store multichannelly the data from the array
- The software must be able to identify cracks by analyzing the input data
(ii) A set of methodologies for monitoring integrity, damage, and failure of concrete components of rail systems will be developed.
5. Design and development of the FK microseismic methodology for monitoring condition and degradation of concrete structures. The measure of the meeting of the objective includes the correlation of the developed methodology with existing UT and Sonic methods for concrete components.
6. A user-friendly software package for non-experts in the microseismic FK method. The measures for the successful completion of the objective include:
- The software must communicate with the array of the microseismic sensors,
- The software must be able to store multichannelly the data from the array,
- The software must be able to apply a two-dimensional fast Fourier transformation (FFT) and to solve the Inverse problem by extracting the modes of Lamb and Rayleigh waves automatically with appropriate adjustments of the initial parameters.
7. The development of a unilateral NMR sensor and a portable NMR equipment for studying microstructure characteristics of mortar and concrete. The measure of the meeting of the objective includes the comparison of the data of the portable NMR devise with corresponding data from laboratory NMR experiments on reference samples with well known microstructure characteristics.
8. A user-friendly software package for non-experts in the NMR spectroscopy. The measures for the successful completion of the objective includes:
- The software must be able to record NMR signals from the portable sensor,
- The software must be able to apply a one-dimensional fast Fourier transformation (FFT) and implement pre-defined NMR pulse sequences.
9. Development of an innovative chemical tool kit for in situ chemical analysis of the concrete structures and market implementation. The measures for the successful completion of the objective includes:
- Ability to identify the chemical properties according to each type and category of deterioration agents which affect the subway concrete structures.
- Ability to identify different types of deterioration patterns.
All the above will be correlated with laboratory measurements on reference samples.
(iii) The Magnetic, Microseismic and NMR devices will be evaluated at Laboratory level.
10. Magnetic laboratory measurements on prototype specimens with predefined defects. The measure of the meeting of the objective includes the comparison with standard NDT tests such as Ultrasonic and Eddy Currents.
11. Microseismic laboratory tests on specimens made of concrete and mortars with controlled porosities, permeabilities, impurities and defects. Compositional characteristics and microstructure properties of the specimens will be examined with conventional laboratory techniques such as Electron Microscopy, Nitrogen and Mercury Porosimetry, Strength Measurements, Ultrasonic, etc. and compared to the microseismic and NMR data. These actions constitute the measure of the meeting of the objective. Specifically, a state of the art microseismic technique will be developed for the investigation of the mechanical properties of concrete using the acoustic module developed in the DIAGNO-RAIL proposal. The level of damage will be inferred by acquiring a seismograph of the concrete specimens, after a mechanical impact at low frequencies. The analysis of the seismograph will be carried out by taking in consideration higher-modes of surface wave propagation, including Rayleigh waves, Lamb waves- both symmetrical and antisymmetrical. This will result to a high resolution mapping of the corrosion versus depth profiles in concrete structures, currently unavailable with standard acoustic methods.
12. NMR laboratory measurements for the determination of moisture content, and the determination of the pore-size distributions in the materials. Standard NMR protocols will be employed. Results obtained from the portable device will be directly compared with the ones obtained from standard laboratory NMR equipment. The above actions constitute the measure of the meeting of the objective. Pore size distributions will be measured with NMR relaxation time measurements, to be carried out using standard NMR equipment and the relevant DIAGNO-RAIL portable device. Moreover, by implementing an inverse Laplace transform, it is possible to deduce pore size distributions from NMR results both at laboratory and on-site. The advantage of the NMR method
is that it allows on-site assessment of the porosity without the need of the expensive transportation of the core samples.
(iv) "On site" measurements with the developed systems will be performed in a rail system.
"On site" measurements with the developed systems were performed in a rail system.
RATP (Régie Autonome des Transports Parisiens) disposes a special carriage for railway inspection of the network. RATP provided free access to the special carriage, where the autonomous imaging hardware was embedded and tested on the RER A line in the Paris region.
Urban Rail Transport S.A. (STASY S.A.) in Athens, Greece, a company incorporated the three rail companies that existed from: AMEL S.A (attiko metro system operation), ISAP S.A (urban rail), and TRAM S.A. (tramway) accepts also to provide access to its railway network for on-site
measurements with the proposed methodologies. These two railroad companies will not be involved whatsoever in the development of the project and will be restricted of access to the know-how of the project and technologies involved.
13. The image monitoring device was performed on 13.650 km of the RER A line between the railway stations of Vincennes and Noisy-Champs at the East of Paris. This railway line is the most frequented of the Paris region with about 1500 trains and 650 000 passengers per day. The field testing allows the verification of:
- the continuous image acquisition and storage processing of images at the inspection speed of 70 km/h covering completely the inspected railway track,
- the adequate quality and definition of images for accurate identification and controlling of the main components and devices of the track,
- the high quality panoramic reconstruction of the inspected railway track and the efficiency of quality control indicators,
- the full automatic identification of sleepers and their localization on the panoramic images of the track
- the accurate automatic measurement of the distance between adjacent sleepers
- the automatic identification of fastening elements on the sleepers and the automatic detection of missing fastening elements
- the accurate measurement of the aperture of thermal expansion devices
- the easiness of use of the extended image processing software and the efficiency of its user guide.
14. On site magnetic crack detection. The condition of rail tracks will be examined in detail. The field implementation of magnetic crack detection and visual detection both placed in a fast moving vehicle will allow the correlation of these two different methodologies. Well established methodologies i.e. eddy current and ultrasound testing will also be performed and the overall aim is to develop a reference database of known track failures and how they are detected by magnetic crack and visual detection in contrast with eddy current and ultrasound testing.
15. The condition of tunnels, bridges, and other structural components of a rail system will be examined and monitored in detail. The advanced methods based on the portable microseismic and NMR devices will be applied on – site on the concrete structures of the rail system. The microseismic method will be assessed in real concrete geometries where higher – modes of surface waves propagation are of critical importance in the analysis of the deterioration profile of the structures and will provide information with respect to the in depth internal integrity of concrete as well as near-surface cracks and materials quality. The measure of the meeting of the objective include comparative field tests on the same rail structures, by applying existing state-of-the-art methods (like advanced IR-Thermography, Electrical Resistivity, Half Cell Potential).
16. The NMR portable device will be used for the on site evaluation of the porosity of the concrete structures in the rail system. An innovative aspect of this project is to perform on site determination of the pore size distribution of core samples extracted from the concrete structure. The measure of the meeting of the objective includes measurements and additional standard tests (IR Thermography, Electrical Resistivity, Half Cell Potential).
All undertaken actions aim (i) to give the partners a competition advantage in the relevant NDT Market (primarily NDT activities concerning maintenance and risk assessment of rail and subway systems in Europe), and (ii) to give an impulse to the academic partners to further develop and promote their applied research in the relevant NDT field.
Project Results:
Within the framework of the DIAGNO-RAIL project the main S & T results/foregrounds are presented below:
1. Portable Magnetic Detection Device
2. Software and User Guide for the Portable Magnetic Detection Device
3. Development of advanced image processing software for visual inspection of rail tracks
4. Extension of advanced image processing software with risk management and maintenance strategies criteria at laboratory scale
5. Development of Portable microseismic device and FK methodology
6. Laboratory Assessment of portable microseismic device. Report on comparison with other methods
7. Development of portable NMR device and methodology
8. Laboratory Assessment of Portable NMR device. Report on comparison with other methods
9. Chemical tool kit and User Guide. Report on Lab and work-site tests
10. Field Evaluation Report for Magnetic Detection device.
11. Field Evaluation Report for the Image Monitor Device in real conditions
12. Field Evaluation Report for acoustic device.
13. Field Evaluation Report for NMR device.
The main features and goals of each project results are described as follows:
1. Portable Magnetic Detection Device.
The objective of this result is the fabrication of a low cost portable device capable to detect cracks, from the magnetic field produced around a crack (stray magnetic field), in a magnetized rail track. The main specifications of the system for the magnetic detection of cracks are the following:
i) Use of GMR sensors as sensors of the field changes caused by the presence of cracks near or on the surface of rail tracks. GMR sensors appear to be the best choice due to their high sensitivity.
ii) Simultaneous real time acquisition of the voltage output signals, produced by an array of GMR sensors, by use of a data acquisition device/PC-card (in short DAQ) connected to a portable PC. It is estimated that it will be sufficient to use a DAQ with the capability of simultaneous acquisition of the signals of up to eight GMR sensors.
iii) The DAQ should be capable of supplying the bias voltage, which is of the order of 10 Volt, needed for the operation of the GMR sensors.
iv) Signal recording and signal analysis of the voltage output signals VOUT of the GMR sensors by the LabVIEW based data acquisition and analysis software running on the PC.
v) Simple self-contained apparatus of small size and low weight for portability.
The development of the portable magnetic detection device consists of an array of magnetic field sensors and a device for magnetization of the rail tracks.
The choice of the main components of the device is real important for the efficient utilization of the system. After a though investigation and a series of experiments the portable magnetic detection device was designed and fabricated successfully consisting of the following main components:
a) Part of the detection device that moves on top of rail tracks:
The moving part of the detection device consists of a magnetic circuit, used to magnetize the rail tack, and the GMR sensors, used to detect the longitudinal component of the magnetic field caused by the presence of cracks:
Magnets: The magnetization of the non-magnetized steel of rail tracks is a crucial step, in order to produce a magnetic field inside it and in external space near it. The abrupt changes in the components of this field, which occur near cracks that exist in rail tracks, form the basis of crack detection. It is necessary to generate magnetic fields of a few kGauss inside rail tracks, in order that the sharp voltage peaks produced by the sensors can be clearly distinguished from electronic noise. Magnetic fields of a few kGauss can easily be generated by relatively small electromagnets. Alternatively, it is possible to use permanent magnets which produce a magnetic field of a few kGauss, like ferrite magnets. Figure 6 shows the assembling of a magnetic circuit consisting from three rectangular pieces of magnetically soft steels (see Figure 6(b)) and two ferrite permanent magnets (SrFe12O19 magnets of Figure 6(a)). The permanent magnets are magnetized perpendicular to their lengths. The magnets of Figure 6(a) and the steel pieces of Figure 6(b) are assembled on the plastic skeleton of Figure 6(c). The result is shown in Figures 6(d) and 6(e). The side shown as upper side in Figure 6(e) is the one that will carry the GMR sensors and will be in contact with the rail tracks during crack detection.
GMR sensors: The GMR sensors that were chosen were the AA and AB series Analog Magnetic Field Sensors of NVE Corporation. More specifically, for the preliminary tests of the detecting device, the GMR sensors that were used were four sensors of the AA002-02 type with field sensitivity 3.0–4.2 mV/(VOe). Figure 7 shows the final form of the part of the detection device that moves on top of rail track: Figure 7(a) shows a general view, while Figure 7(b) shows specifically the printed board with the four sensors fixed on it. On the printed board are also fixed five coaxial cables with BNC connectors: one for the input biasing voltage of the GMR sensors and four for the output voltage signal VOUT produced by them due to the presence of longitudinal component of the stray magnetic field.
b) DAQ for collection of analog signals from GMR sensors and A/D conversion:
The analog voltage signals produced by the GMR sensors are collected and processed by a commercial data acquisition device (DAQ) purchased by “National Instruments”. The type of the device is “NI USB-6212 BNC” (see Figure 8) and is capable of collecting and digitizing 8 different analog voltage signals (16-bit, 400 kS/sec). The particular model incorporates a voltage source used to polarize the GMR sensors and can be connected to a PC through a USB port.
c) PC with data acquisition and data analysis software
The final component of the detecting device is a LabVIEW based software running on a portable PC. The software is designed to collect the digital signals produced by DAQ, store the signals to a hard disk and perform signal analysis for the detection of cracks.
2. Software and User Guide for the Portable Magnetic Detection Device.
The objective of this result is the development of user friendly software necessary for the proper operation of the magnetic detection device that is used for the magnetic detection of cracks on rail tracks. The developed software is based on the LabVIEW 2009 application. This application is capable: (a) of controlling all the parameters of the measuring process, such as biasing voltage VB and sampling frequency fS, and (b) for simultaneous real time acquisition of the voltage signals of the GMR sensors. This real time acquisition involves the control of the sampling frequency, of the analog-to-digital (A/D) converter integrated in the DAQ device, by the developed software. A reasonable choice for the needed software is to develop a LabVIEW based application, which is used for communicating/controlling the DAQ device.
Within the framework of the project a user friendly LabVIEW based software is successfully developed that allows the user to easily adjust the values of all the parameters that are relevant to the measuring process, through an easily understandable graphical user interface (GUI). The application of the software is mainly the communication between the PC and the DAQ device, the adjustment of all the parameters that are relevant to data acquisition and the testing of the data acquisition process in laboratory conditions. Based on tests made on rail tracks, where we have deliberately created cracks on their surfaces in order to test the device, we can argue that the instrument is capable of detecting cracks on rail tracks by measuring the changes caused by these cracks on the magnetic field produced inside the tracks.
3. Development of advanced image processing software for visual inspection of rail tracks.
The objective of this result is the development of an image processing software that is able to generate a panoramic image of the track by stitching series of successive images with varying degrees of overlapping. The panoramic image of the track is an essential tool for safe and accurate visual inspection and control of the state of the main elements and devices of the track (rails, joints, connections, attachments, sleepers, ballast, crossing and thermal expansion devices).
The advanced image processing software is successfully developed to stitch sequences of overlapped images and to provide continuous panoramic image of the track. This software includes powerful algorithms free from random movements of the camera during image acquisition and variable conditions of lighting. The panoramic image generation is a result of great number of key-points detection, key-points matching, image blending and image merging using a transformation estimates from one image to another based on four parameters: longitudinal translation, lateral translation, rotation and scale. On the other hand, computing time is incompatible with real time processing of images. Further developments have been performed from panoramic image of track. Firstly, the measurement of characteristic distances of thermal expansion devices which is essential for functioning control. Secondly, the automatic detection of the presence or absence of main elements of the track (anchor bolds).
4. Extension of advanced image processing software with risk management and maintenance strategies criteria at laboratory scale.
This result concerns the extension of the image processing software to the monitoring of rail track main defects for risk management and maintenance
strategy. Using forms recognition and including specific criteria and thresholds, the extended image processing software is able to control the rail integrity, to identify sleepers, and connections to control the presence of bolts and screws, to measure distance between sleepers and aperture of thermal expansion devices and identify main defects. Consequently, the extended image processing software provides all necessary information for the development of a decision making system for risk management and maintenance strategy.
In particular, the extension of the advanced image processing software provides full automatic monitoring of the track’s components and detection of their main defects using powerful algorithms. Moreover, the extended image processing software provides precise image of the current state of the track’s components that could be compared with the previous states and supply information about the progressive wearing and the aging of components and evolving of low risk defects. All this information is the essential input for a decision-making system for risk management and maintenance strategy and scheduling.
Risk management analysis is based on assessment of the consequences resulting from nonintervention on the component or the defect. For each intervention the risk’s frequency and the risk’s gravity have to be quantified with the aim of determining a global risk index evaluating the risk taken from non-intervention on the railway track. The value of global risk index is the main tool for risk management of the rail track and determines the priority of the intervention.
Moreover, the maintenance strategy for every reference period could be established on the base of a matrix of the values of global risk index for the components of the rail track and the interventions for each component, using adequate thresholds.
5. Development of Portable microseismic device and FK methodology.
This result involves the implementation of the microseismic FK method at frequency range 1-40 kHz for analysis and assessment in the weathered or delaminated concrete. The implementation of the method includes the assembly of appropriate modules, the accelerometers arrays, the impact hammer in one portable unit along with a preliminary software capable or acquiring the microseismic signals and analysing them according to the FK methodology.
The characteristic of the current seismic methods is that they operate at low frequencies (5 kHz - 60 kHz) making them suitable of yielding small strain mechanical modulus as a function of depth in concrete structures. The Innovation of the proposed microseismic method concerns the implementation of an advance signal analysis that takes into account the different surface waves that are produced in a confined geometry of real concrete structures (Lamb and Rayleigh waves) and solves the fundamental and higher-order modes of such surface waves. The method resolves fundamental and higher-order modes of both Lamb and Rayleigh waves to accurately evaluate concrete quality with depth.
The objective of this result is the implementation of the FK methodology in a state of the art, portable device, assembled from acoustic modulus. This device, in conjunction with the advanced signal analysis is used for in-field microseismic measurements in weathered or delaminated concrete. The main specifications of the FK device are the following:
i) Synchronization of up to five accelerometers for real time acquisition of acoustic signals in order to record a seismograph of over 16 instances. Synchronization is a critical part of the whole process, especially between the various sets of the five signals.
ii) Correlation of the impact hammer signal with the trigger of the accelerometers. The generation of the acoustic signal by the impact hammer must be correlated to the trigger of the accelerometers for synchronization issues and for the automated process of the data files.
iii) Signal recording and signal analysis.
iv) Simple self-contained apparatus of small size and low weight for portability.
For the development of the portable, microseismic device with the above specifications, a selection of state of the art acoustic modules is performed. The assembly of the modules is designed in order to achieve minimum volume of the final device for best portability. Thus, the main components of the developed FK microseismic device are the following:
a) A/D converter – Current stimulator
The A/D conversion of the data is based on a National Instrument PC card capable of driving eight accelerometers while also providing the current stimulation to them prior to trigger. The developed software allows the simultaneous recording and display of sets of data from up to seven accelerometers.
b) External Trigger
Triggering is accomplished in two ways depending on the experimental needs.
- The signal from the impact hammer triggers a circuit that generates a TTL pulse. This pulse is driven to the external trigger jack of the National Instrument PC card which drives the accelerometers.
- The signal of the impact hammer is driven to the channel 0 of the National Instrument PC card which drives the accelerometers.
c) Impact hammer
The impact hammer is a PCB piezotronics instrument. The hammer has several different impact tips in order to modify its frequency response and additional weight module. The frequency response of the impact hammer has a Gaussian like shape and its signal can be recorded via a BNC jack.
d) PreAmplifier
The pre-amplifier is used to amplify the signals from the accelerometers. The use of pre-amplifier is optional, depending on the experimental conditions.
e) Accelerometers
The accelerometers are from PCB piezotronics and are high sensitivity ceramic shear accelerometers with resonance frequency up to 50 kHz.
f) PC
The PC is a National Instruments PC mounted in a PXI-1002 rack along with the microseismic card. The whole system is portable and lightweight.
A state of the art, portable, FK microseismic device, is developed and implemented successfully. Based on the preliminary tests of a floor concrete sample we can argue that the instrument will be capable of measuring the mechanical parameters of concrete structures as well as to estimate their thickness.
6. Laboratory Assessment of portable microseismic device. Report on comparison with other methods.
The objective of this result involves the laboratory assessment of the the capability of the FK microseismic device and methodology by using
laboratory test specimens with different compositional characteristics, such as porosity and defects. As a result the advantages and limitations of the techniques and instruments developed and presented in result 5 are evaluated and validated at laboratory level for the specific materials. In addition, complementary NDT techniques together with strength tests have been used at laboratory level for the assessment of the device.
In order to evaluate the microseismic device a series of concrete samples were fabricated. These samples vary on composition and induced defects (from thermal treatment) and were fully characterized by standard methods (compressive strength, ultrasonic and impact echo measurements). In addition, two concrete walls with different thickness were tested and carrots were extracted to conduct strength measurements.
The main issues that were addressed during the laboratory evaluation of the microseismic device were the standardization of the experimental parameters. Specifically, we conducted experiments to determine the optimum experimental parameters for:
a. the trigger method
b. the best coupling of the accelerometers to the concrete wall
c. the initial distance of the impact from the array of accelerometers
d. the weight of the impact hammer in relation to the desired excitation frequency range
e. the distances within the array of the accelerometers.
f. Multichannel method and FK method.
Thus, the FK microseismic device is evaluated and validated successfully. Specifically, the device is tested on concrete samples and on test walls. By a series of experiments and testings the experimental procedure is finalized. The results from the conventional methods (impact echo and acoustic measurements) confirmed the results of the microseismic device within accepted deviation. The experiments on the test walls validate the capability of the device to measure and detect crucial parameters of the structures like the thickness and the mechanical characteristics (Poison ratio, Young modulus).
7. Development of portable NMR device and methodology.
This results involves the development of an NMR sensor, which is adjusted in portable NMR equipment for studying microstructure characteristics (specifically the pore size distribution) of stone, mortars, concrete, and other materials. The 1H NMR method has the advantage that it is a fast, non-invasive technique, capable of monitoring the microporosity in real time. The development of the instrument includes the design and construction of the magnet and the coil for the investigation of core samples extracted from the concrete structure. The innovation of the probe developed is determined by its capability to assess on site the porosity and the pore size distribution of water saturated core concrete samples extracted from concrete structures.
The objective of this result is the implementation of a state of the art, portable, solid state NMR spectrometer, assembled from solid state electronic modulus. This spectrometer, in conjunction with a portable permanent magnet is used for in field NMR measurements of core drilled samples. The main specifications of the NMR spectrometer for these particular experiments are the following:
i) Low applied magnetic field in order to reduce magnetic susceptibility differences between the solid phase and the fluid filling the pore space in NMR experiments in porous materials. These differences lead to field inhomogeneities inside the pore space, often called ‘internal gradients’ and can affect NMR measurements in various ways.
ii) High signal to noise ratio and fast recovery for the detection of the weak NMR signals with short relaxation times encountered in the NMR experiments of porous materials and particularly of core drilled samples which contain many paramagnetic impurities.
iii) Simple self-contained apparatus of small size and low weight for portability.
For the development of the portable, solid state broadband (2 – 800 MHz) NMR spectrometer with the above specifications, a selection of state of the art solid state electronic modules is performed. Subsequently, an assembly of the modules is designed in order to achieve minimum volume of the final spectrometer for best portability. The main components of the developed NMR spectrometer are the following:
a) Transmitter Section
The transmitter section is the part of the spectrometer that generates the radiofrequency (rf) needed for pulsed NMR. It consists of rf synthesizer, phase shifter and gating circuits, and rf amplifier.
b) PC based programmable pulse generator
The pulse generator is based on a National Instrument PC card capable of producing pulses with a minimal duration of 0.6 μsec. The software for the programming allows the design of pulse sequences including the specification of the number and the duration of the pulses, the intervals between them, their repetition time, etc.
c) RF synthesizer
The rf synthesizer is a radiofrequency source (10 kHz – 1000 MHz signal generator) which produces a stable frequency which can be set precisely and can be readily controlled by the computer interface. It creates the frequency signal for the spectrometer and is usually at a low level (a few mW).
d) The pulse gate
The signal from the synthesizer is controlled by a pulse gate. The pulse gate is a fast switch which is opened at defined moments to allow the production of rf pulses. We have used a series of broadband rf switches and phase shifters (DC – 5 GHz, Mini Circuits) which create the rf excitation pulses with certain phases, durations etc., controlled by the PC based programmable pulse generator.
e) Power amplifier
The power amplifier is used to amplify the rf excitation pulses. The amplifier (Tomco Technologies) is broadband within the frequency range 0.5 – 150 MHz, capable of supplying 250 Watts at the desired frequency of operation. The amplifier operates in class AB and is designed for pulse and continuous wave applications.
f) Duplexer
The signal from the power amplifier is guided to the probe head. The returning spin signal is directed to the preamplifier. The duplexer directs the strong rf pulse from the amplifier into the cable leading to the probe and not into the sensitive signal detection circuitry. On the other hand, it diverts the weak signal coming from the probe to the receiver section. We used a home made duplexer based on the impedance mismatched effect in the λ/4 circuit (CLC-π-circuit, λ is the wavelength).
g) Tank circuit in the probe head
The probe circuit is a tuned LC circuit, impedance matched to 50 ohms at the resonant frequency for efficient power transmission to the sample. The inductor L in the circuit is the sample coil, which is connected to ground at each end through tunable capacitors Cpar and Cser, to allow frequency and impedance matching. Power in and signal out pass through the same point on the resonant circuit, so that both the power amplifier and the signal preamp have a properly matched load. Between the power amplifier and the probe there is a pair of crossed diodes which shows high series impedance when the transmitter is off and low impedance during the pulses.
h) Receiver Section
The receiver section is where the NMR signals are detected and processed. It consists of preamplifier, quadrature receiver, and analog to digital converter.
i) Preamplifier
The preamplifier amplifies the weak NMR spin signal and sends it to the spectrometer. The preamplifier is a high-gain, wide-band module (5 – 600 MHz, 67 dB gain, 1 dB noise figure, MITEQ Inc.), which allows to achieve the necessary level of amplification of the NMR signal in one stage. Antiparallel diodes are set to the ground before the preamplifier to prevent damage on it through extruding remnants of the pulse. In this way voltages over 0.6 V are absorbed.
j) Receiver
The receiver utilizes two Mini Circuits (33 dB gain) amplifiers as gain stages. Dual phase-sensitive (quadrature) detection is accomplished directly at the NMR frequency without any intermediate conversion stages, using Mini Circuits mixers, splitters and a quadrature hybrid. Specifically, the signal after amplification is directed to a Mini Circuit splitter and the two signals are subsequently feed to two mixers (Mini Circuits) where they are mixed with two 90 degree out of phase reference signals coming out from the frequency synthesizer.
k) Analog-to-Digital Converter
The demodulated NMR signals are directed to low pass filters (pass-band DC- 1.9 MHz) and then are digitized using a two port National Instrument analog-to-digital ADC converter card interfaced with the computer.
l) Assembly of the system
Using the electronic units associated with the spectrometer, the assembly of the modules was performed according to the minimum volume design The assembly is arranged in three different layers and a very small volume has been achieved using as short rf cables as possible.
The portable broadband NMR spectrometer was coupled to a circular Halbach array magnet, which provides a uniform field in a compact format.
The implementation of a portable, pulsed solid state NMR spectrometer is successfully completed. The spectrometer is assembled from up to date solid state electronic modulus. The instrument allows the performance of NMR experiments in low external magnetic fields. The instrument exhibits good signal to noise ratio and fast recovery considering the low operational frequency. Finally the instrument is portable of relatively small size and robust. Based on preliminary laboratory tests we can argue that the instrument is capable of measuring the pore-size distribution of various saturated core samples of different origin.
8. Laboratory Assessment of Portable NMR device. Report on comparison with other methods.
This result involves the laboratory assessment of the portable NMR equipment. The main objective concerns NMR laboratory measurements on test specimens for the determination of moisture content, and the determination of the pore-size distributions of the samples. Standard NMR protocols are employed. Results obtained from the portable device are directly compared with the ones obtained from standard laboratory NMR equipment. In particular, pore size distributions are measured with NMR relaxation time measurements, carried out using standard NMR equipment and the relevant DIAGNO-RAIL portable device. Moreover, by implementing an inverse Laplace transform, it is possible to deduce pore size distributions from NMR results. The interpretation of the results contribute to the improvement of precision characteristics of the p-NMR. The advantage of the NMR method is that it allows on-site assessment of the porosity without the need of the expensive transportation of the core drilled samples. Composition characteristics and microstructure properties of the test specimens are also studied with conventional laboratory techniques and complementary advanced non-destructive techniques (NDT) are used at laboratory for the assessment of the device.
In order to evaluate the portable NMR device various test specimens were examined which were consisted of materials similar to the materials and structures mainly used in the railway system, e.g cement pastes, concrete, mortars and stones. The samples were examined in order to determine their pore-size distributions using conventional laboratory techniques and both laboratory and portable NMR instrumentation. The samples were prepared with different composition characteristics, microstructure and salt and water content.
The evaluation procedure of the portable NMR device includes three steps:
a) NMR laboratory measurements for the determination of moisture content, and the determination of the pore-size distributions of the test samples. The pore size distribution of the samples was measured with NMR relaxation time (T1) measurements using standard NMR equipment and the relevant DIAGNO-RAIL portable device. The experiments were carried out using standard NMR protocols, which included similar NMR probes, resonance frequency, pulse sequence and NMR parameters, acquisition program and data analysis procedures. The results obtained from both instrumentations were directly compared.
b) Conventional laboratory technique such as Mercury Intrusion Porosimetry was used to determine the pore-size distribution of the samples and validate the NMR measurements.
c) Complementary advanced NDT techniques were used at laboratory for the assessment of the device.
The laboratory evaluation of the DIAGNO-RAIL portable, pulsed solid state NMR spectrometer was successfully completed. The p-NMR instrument was capable of measuring the pore-size distribution of various water saturated samples of different origin. The NMR results obtained from the p-NMR device were directly compared with the ones obtained from the c-NMR device and it was shown that the data are in general good agreement. In addition, it was found the p-NMR relaxation time measurements were well correlated with the results obtained from the conventional MIP experimental measurements. Therefore, the p-NMR device is proven to be a reliable and valuable tool in determining the pore-size distribution and porosity of any given water saturated cementitious material.
9. Chemical tool kit and User Guide. Report on Lab and work-site tests.
The aim of this result is to develop all-in-one chemical kit for the in-situ qualitative and quantitative characterization of the most severe deterioration agents (e.g acidity, chlorides and sulphates, depth of carbonation), as well as, the development of an easy to apply methodology for the field surveys.
An extensive market analysis of available simple tests and microchemical kits, as well as portable instruments able to determine the nature of the ions/
salts and their concentration levels within concrete structures was carried out. On the basis of the above research and market analysis it was decided that the chemical kit must incorporates simple tests for semi-quantitative determination of water soluble ions, such as paper strips, microchemical and colorimetric kits by Merck, together with portable instrumentation, consists of a UV-Vis Photometer NOVA 60 A and a customized system using suitable pairs of Ion Selective Electrodes each time, for chloride, sulphate and nitrate determination.
The developed kit was based on the combination of the above suggested procedures. The kit was tested and calibrated in laboratory on test specimens prepared in collaboration with partner NTUA, with preset concentrations of chloride and sulphate salts, while additional effort was made in order to simplify the in-situ procedure and minimize the required amount of material sampled.
The on-site evaluation of the chemical kit was conducted in subway constructions (AMEL S.A (attiko metro system operation)) of the Urban Rail Transport S.A. (STASY S.A.) in Athens, Greece. For the monitoring of the penetration depth of chlorides into concrete lining of the tunnel samples were collected by drilling at different depths from the surface (5mm, 1-2 cm and 3-5 cm). Two different sampling areas of the concrete lining were selected bearing whitish
efflorescences, along with samples of whitish material from the encrustations and water samples from the inflows in the tunnel.
It was concluded that the results obtained both in laboratory and field applications are in good agreement with traditional laboratory tests and therefore it is concluded that the proposed chemical kit can be effectively used for routine monitoring of preservation condition and identification of risk factors in concrete structures.
10. Field Evaluation Report for Magnetic Detection device.
The aim of this result this result is the the field evaluation of the magnetic crack detection device in real work site conditions (a train station for example).
The field evaluation of the magnetic crack detection device was conducted at the railway infrastructures of “URBAN RAIL TRANSPORT S.A.” (or “STASY S.A.”) at Athens, Greece and the measurements showed that the instrument was capable of detecting defects in rail tracks by measuring the changes caused by these defects on the magnetic field produced inside the tracks
The capability of the instrument to provide accurate values of quantitative parameters that describe the geometrical characteristics of detected defects is still under investigation, but nevertheless it was quite obvious that the system was able to detect the position of cracks and defects by producing voltage peaks when it moved above them. The system was also capable of recording accelerations or decelerations of the cart of the detection device, which make the recorded signals more complicate but could possibly be used as extra information when it is not feasible to maintain the speed of the device at a constant value (for instance when moving the cart by hand).
11. Field Evaluation Report for the Image Monitor Device in real conditions.
This result involves the field testing of the whole image processing device in order to verify its efficiency for making automatic inspection of the railway track and providing critical input for risk management and maintenance strategy.
The field testing of the image monitoring device was conducted at RATP (Régie Autonome des Transports de Paris) one of the main French Railway Companies.
The image monitoring device was tested successfully in field conditions in the Paris region where more than 37,000 images were acquired from 13,650 km railway track and treated by the final version of the extended image processing software. 1,953 panoramic reconstructions of the railway track were produced by automatic image stitching.
The quality of the panoramic reconstructions of the railway track was evaluated by means of customized algorithms and specific criteria and thresholds implemented in the extended image processing software with the aim detecting any anomaly and providing reliable panoramic images.
The panoramic reconstructions of the railway track were used successfully for identification, detection and controlling of main track elements. Firstly, the sleepers were identified en their distance was measured for controlling any movement from their initial place in the track. Secondly, the fastening elements present on the sleepers and ensuring the mechanical connection of the rail with the sleeper were detected. More than 50,000 bold, nuts or screws
were controlled and lesser than 0.4% was identified as missing. With these results the field testing demonstrates that the image monitoring device is able to provide accurate and reliable critical information for risk management and maintenance strategy of the railway track.
Finally, using customized algorithms implemented into the image processing software, the image monitoring device can easily include new functionalities as the recognition and localization of main rail defects as for example, rail corrugation, splintering or lateral wearing providing complementary critical information for a making-decision system for risk management and maintenance strategy.
12. Field Evaluation Report for acoustic device.
This result involves the evaluation of the microseismic device in field conditions. The in-field measurements were conducted at the rail network of the Urban Rail Transport S.A. (STASY S.A.) in Athens, Greece. This company incorporates the three rail companies operating in Athens and include: AMEL S.A (Attiko metro system operation), ISAP S.A (urban rail), and TRAM S.A. (tramway). In particular, the in-filed measurements of the microseismic device were conducted in the concrete supporting plates of the rails at the rail system of AMEL (metro company of Athens). The field measurements were conducted at the rail network between the stations “Nomismatoskopio - Ag. Paraskevi” and between the stations “Holargos – Ethiki Amyna”, during the maintenance hours of the AMEL (from 01:00am to 04:30am).
The measurements were conducted in selected areas:
a. near the walkway,
b. besides the rails,
c. at the area below the third rail.
Furthermore, the measurements were conducted at selected points between the rail stations:
a. at points of high humidity,
b. at points of great rail curvature where the load on the cement plates is greater
c. and for reference purpose, at completely dry and straight points where the cement plates are expected to be intact.
All the results from the field measurements were consistent with the tunnels outline as provided from AMEL. We were able to detect the actual depth of the concrete support plates in most cases. We conducted measurements on sites where the cements plates are expected to be intact (at the entrance of the stations and below the third line) for reference purposes. We were able to detect deterioration of the concrete plates consistent with the environmental parameters (high humidity, great curvature).
Overall, the microseismic device was proven reliable in field conditions.
13. Field Evaluation Report for NMR device.
This result involves the field evaluation of the portable NMR equipment on concrete structures and in particular the capability of the NMR device in real work site conditions. The field measurements were conducted at the rail network of the Urban Rail Transport S.A. (STASY S.A.) in Athens, Greece. This company incorporates the three rail companies operating in Athens and include: AMEL S.A (Attiko metro system operation), ISAP S.A (urban rail), and TRAM S.A. (tramway). In particular, the on – site application of portable NMR equipment was conducted using core samples extracted from the infrastructure of the rail system of AMEL S.A (Attiko metro system operation). AMEL S.A. is a state company of high scientific training, which based on reliable scheduling and systematic work, implements the development of the Athens Metro network.
The field measurements were conducted at the rail network between the stations “Nomismatoskopio - Ag. Paraskevi”, and between the stations “Holargos – Ethiki Amyna”, during the maintenance hours of the AMEL S.A. (from 01:00am to 04:30am). Different samples were extracted from the building structure (tunnel, walls, etc) of the metro stations. These core samples were extracted from areas of the tunnel with increased moisture level, leakage of water and areas with salt efflorescence on the surface. The selection of these areas was mainly based initially on visual inspection of the concrete structures following a detailed thermographic survey for a full proof evidence for moisture presence beneath the surface.
The extracted samples were measured with the portable NMR equipment in order to evaluate the porosity of the samples and to determine on-site the pore-size distribution. The pore-size distribution of the extracted core samples was determined by measuring the T1 and T2 1H NMR relaxation times.
The NMR measurements showed that the instrument is capable of the on-site determination of the pore size distribution in defected concrete structures. It is proven that the evaluation of the pore-size distribution can provide an estimate concerning the integrity of such large scale structure and thus, the capability of the instrument to provide results in real work site conditions is established successfully.
Finally conventional state-of-the-art inspection techniques were used such as Infrared Thermography, Electrical Resistivity, Half Cell Potential, corrosion current density measurements in order to evaluated the preservation state of the similar railway tunnels measure above of the AMEL. From the diagnostic studies, it was deduced that infrared thermography can provide significant information about the moisture mapping providing real-time results in such types of inspections. In particular it can be used efficiently for the assessment of large scale concrete constructions as well as to disclose any subsurface features. On the other hand, Electrical Resistivity, Half Cell Potential, corrosion current of steel reinforcements and GPR provided information regarding the condition of the concrete structure and its corrosion gradient on regions where humidity was detected through the thermographic monitoring. These results from the inspection methods correlate very well with the results obtained from the field evaluation of the microseismic and NMR device.
Potential Impact:
The overall aim of the project is to develop an integrated system of state-of-the-art NDT methodologies to improve risk assessment and failure prediction concerning the integrity and functionality of rail systems, in favour of the participating SMEs and is divided in two main areas of application:
Inspection of Rails with precise Visual and Magnetic ac-Susceptibility methods and Inspection of concrete elements of the rail system with on site Acoustic, and Nuclear Magnetic Resonance (NMR) methods combined with a chemical tool kit for in situ chemical analysis measurements.
The main guidelines of the overall dissemination strategy are:
a) Development of awareness, transfer and publicity activities for the industrial and research communities, as well as for the general public.
b) Publications of scientific papers.
c) Organization of presentations and trials as standalone activities of the project or within relevant conferences in the area.
d) Design and production of publishing materials in both printed and electronic form.
e) Development and maintenance of a web site dedicated to the project.
f) Network and established distribution channels of the individual partners.
In the first reporting period, the following results have been achieved:
i) Selection of appropriate project logo
ii) Project Factsheet
iii) Project flyer
iv) Project presentation
v) Set up of the project website, maintenance of News section and other contents (public and members area, project repository)
At the end of the project the following dissemination activities were completed:
i) Conferences releases
ii) Published field results
iii) Promotional material forwarded to end-users
iv) Presentations to end-users
v) Update of the promotion material and the website
DIAGNO-RAIL logo
A logo for the DIAGNORAIL project has been selected and will be attached as a separate file in this report.
DIAGNO-RAIL Factsheet
The project Factsheet is a two-pages folder containing four sections: At a glance (with the main figures of the project), Overview, Challenges and Activities. The Factsheet will be attached as a separate file in this report.
DIAGNO-RAIL Flyer
The DIAGNO-RAIL flyer contains a title page, a page with all partners’ logos, the name and address of the co-ordinator. The other three pages contain an overview of the project, a description of challenges for each of the proposed methodologies of the project and characteristic images of the results (Figure 3). The Flyer will be attached as a separate file in this report.
DIAGNO-RAIL Web site
The DIAGNO-RAIL web site was established in two steps: at first only for internal use, then for public dissemination (http://www.ims.demokritos.gr/diagnorail). The home web page of the project includes general information about the project and the overall aim of the project. There are six different links available:
a) The Project
b) News & Events
c) Partners
d) Documents
f) Progress
g) Forum
“The Projects” link includes information about the main objectives of the project, the materials under investigation and the innovative methods which are used in the DIAGNO-RAIL project. Also there is a link to the European Commission CORDIS web site, where there is direct information about the funding sources, the project description, details and participants.
The “News & Events” link includes information regarding the news, press, events and meetings that will take place during the progress of the project. This section shares information regarding all the project activities that helps promote the DIAGNO-RAIL project. These activities include the published joint papers in peer-reviewed international journals and the presentations at international meetings and conferences. Moreover, all the review meetings between the partners are listed.
In the “Partners” link a description of the Consortium as whole is presented. The Consortium comprises of seven participants. The selection criteria of the specific seven participants for the completion of DIAGNO-RAIL project are given in detail. A general profile of each partner is presented with all the contact information and the name of the responsible person.
The “Documents” link includes the newsletter, publications, performance reports and file manager. These documents are important for maintaining communication with each partner, for promoting the DIAGNO-RAIL project to the public and also for promoting a wider use of NDT techniques in the field of railways and construction. In the “Progress” link there is detail information regarding the work packages, the tasks, the deliverables and the milestones of the DIAGNO-RAIL project. In this section tables and GANTT charts are presented showing each month the timing and status of the work packages, tasks, deliverables and milestones of the DIAGNO-RAIL project.
The “Forum” link is for communication purposes between the DIAGNO-RAIL partners and also it is a place where people discuss topics related to non-destructive testing, decision-making and policies. In particular, during the project, mailing lists will be requested from existing European networks or target groups related to the field of non-destructive testing, and will be prompted to register DIAGNO-RAIL’s portal. Workpackage leaders are responsible for disseminating the results of their respective Workpackage to the target groups. Target groups include professional organizations and Non-Destructive Testing Societies.
Conferences
DIAGNO-RAIL results were presented to the following International conferences.
1. ICNNAI'2012 - The 7th International Conference on Neural Networks and Artificial Intelligence
October 10-12, 2012
Minsk, Belarus
Scope of the conference:
The aim of the conference is to present and discuss research results and their applications, to support and accelerate world-wide exchange of ideas. The continuous exchange of scientific and technical information is of particular importance for the research and the transfer of research to practice. The scope of this conference covers the theory and application of neural networks and techniques of artificial intelligence. New techniques, instruments and both software and hardware components are included. ALCON and UCP contributed to the above conference with a paper:
"Railway track inspection using artificial vision"
A. Belhaoua, J. L. Gallias, N. Renault, V. V. Bui and P. Faucon
This contrition involved the visual inspection of the rail track using an advanced image monitoring method and an advanced image processing software for fast and reliable assessment of track failure and damage.
2. 12th International Conference on Recent Advances in Concrete Technology and Sustainability Issues
October 30- November 2, 2012
Prague, Czech Republic
Scope of the conference:
This conference includes topics in Advances in Geological CO2 Sequestration and Co-Sequestration with O2; Self-Compacting High-Performance Concretes; Dynamic Performance of Eco-Friendly Prestressed Concrete Sleeper; Parameters Influencing the Performance of Shrinkage-Compensating Concrete, and much more.NTUA contributed to the above conference with the following papers:
a) Corrosion Inhibitors and Macrogalvanic Cells.
G. Batis, E. Zacharopoulou, A. Zacharopoulou.
b) Novel Concrete Coating Materials: Physicochemical Characteristics and Performance Evaluation against Corrosion
Th. Zafeiropoulou, E. Rakanta and G. Batis.
This contrition involved the compositional characteristics and microstructure properties of concrete examined with conventional laboratory techniques. This activity was important as the conference was international involving people from around the world, which aids the promotion of build in this project.
All the above dissemination activities are important as all the conferences were international involving people from around the world and thus raise the public awareness with regards to the research work of the project, the achievements of the project and all these results to the promotion of the integrated system that was built in the DIAGNO-RAIL project.
Publications
DIAGNO-RAIL results were published under the following titles:
1. Railway track inspection using artificial vision
A. Belhaoua, J. L. Gallias, N. Renault, V. V. Bui and P. Faucon
This paper (6 pages) is a contribution from ALCON and UCP and was accepted and published in the conference proceedings of the seventh International Conference on Neural Networks and Artificial Intelligence.
2. Inspection of Railway Track Fastening Elements Using Artificial Vision
A. Belhaoua, J. L. Gallias, N. Renault, V. V. Bui and P. Faucon
This paper is a contribution from ALCON and UCP and is submitted to the international scientific review "Transportation Research" and is 23 pages.
The above dissemination activities are important as the publications give the opportunity to promote the DIAGNO-RAIL project to the general public through the internet given details about the capabilities of the developed methodologies as well as the direct and powerful applications.
DIAGNO-RAIL Presentations
A presentation of the DIAGNO-RAIL project has been developed in order to be addressed to an end-user network. It contains technical information for each proposed methodology of the project and the expected overall benefits. A comparison with the existing state-of-the-art methods is conducted and preliminary results are presented. This presentation was presented to the Urban Rail Transport S.A. (STASY S.A.) in Athens. Greece. This company incorporated the three rail companies that existed up to that point: AMEL S.A (attiko metro system operation), ISAP S.A (urban rail), and TRAM S.A. (tramway). The goal of this presentation was to present the concepts and capabilities of the project along with other promotional materials in order to establish a potential end-user interest for the DAIGNO-RAIL project. Thus, ENDITECH S.A (the coordinator) has managed to establish new contact and promote the developed technologies to STASY S.A. who showed a big interest and agreed to provide access to its railway network for the on-site measurements with the proposed methodologies, which include in-field test of the Magnetic Crack Detection Device, in-field test with the FK microseismic device/methodology and on – site application of portable NMR equipment.
Moreover, many contacts have been taken by Alcon Diaz Consulting and by the University of Cergy- Pontoise during the DIAGNO-RAIL project with three main French Railway Companies, as such as RATP (Railway network company of the Paris region), SNCF (French National Railway Corporation) and EUROTUNNEL (French-English railway company operating under the Channel) for making advertising about DIAGNO-RAIL project, and particularly image monitoring device, and for negotiating field testing with the higher impact. Finally, RATP (Régie Autonome des Transports de Paris) offered the best conditions for the testing, providing, as 2 years ago (see report of June 2011, deliverable 2.1) a special railway carriage for testing.
A demonstration of the DIAGNO-RAIL project was carried out at the STASY S.A site (metro company of Athens) and in France (RATP).
The dissemination and exploitation of project results is significant to DIAGNO-RAIL project. A final plan of the dissemination strategy of the DAIGNORAIL project was concluded and certain measures in the dissemination and promotion of project results were taken to diffuse the capabilities of the project to the different professional, political and social groups. The underlying goal of the dissemination plan was to promote the idea of maintenance and quality of public works into the society and to create links among researchers, end-users, and decision-makers.
List of Websites:
The official website of the project for the public awareness has been developed and the web page address is the following:
http://www.ims.demokritos.gr/diagnorail
The DIAGNO-RAIL web page is hosted at the Institute of Materials Science, N.C.S.R. "Demokritos", Greece. It is a dynamic web page, which can be modified by registered users. Furthermore, a file manager provides data exchange between registered users.
Railways are one of the prime modes of transportation in European Union and as they are closely associated with intensive passenger and cargo transportation, they own high risk in terms of potential loss of human life and damage/destruction of assets. New technologies and stringent safety standards are constantly being introduced, to reduce risks associated with derailments and collisions. A detailed assessment of the defects which emerge both in the rolling stock and the rail infrastructure is essential to apply the correct maintenance strategy. At the same time large span or segmental bridges and tunnels, which are important parts of rail systems are particularly susceptible to deterioration with increasing risk of failure due to often-harsh and aggressive environments, in combination with aging and increasing traffic load. Evidently, efficient maintenance strategies of complex rail systems, which are based on fast and reliable inspection methods, can reduce significantly potential risks and cost. The overall aim of the project is to develop an integrated system of state-of-the-art NDT methodologies to improve risk assessment and failure prediction concerning the integrity and functionality of rail systems, in favour of the participating SMEs. In particular precise Visual and Magnetic ac-Susceptibility methods, for fast and reliable assessment of track failure and damage will be combined with state-of-the-art Acoustic, and Nuclear Magnetic Resonance (NMR) portable devices appropriate for examining the performance of concrete structures, in order to gain critical information concerning the performance, damage risk, and condition monitoring of rail and subway systems. In parallel an innovative chemical tool kit will be developed for in-situ chemical analysis measurements, which in combination with modern established analytical techniques will be used to characterize in-situ materials.
Project Context and Objectives:
Railways are one of the prime modes of transportation in European Union and as they are closely associated with intensive passenger and cargo transportation, they own high risk in terms of potential loss of human life and damage/destruction of assets. New technologies and stringent
safety standards are constantly being introduced, to reduce risks associated with derailments and collisions. A detailed assessment of the defects, which emerge both in the rolling stock and the rail infrastructure, is essential to apply the correct maintenance strategy.
Some of the rail degradations include worn out rails, weld problems, internal defects, corrugations and rolling contact fatigue (RCF) initiated problems such as surface cracks, head checks, squats, chipping and shelling. On the other hand, the attachments between rail and sleepers could be damaged, broken or missing, the quality of the ballast deteriorated. If undetected and/or untreated, these defects can lead to rail breaks and derailments.
The consequences of derailment in terms of loss of human life, damage/destruction of assets and loss of company trust and reputation justify maintaining stringent safety standards, which require massive rail maintenance investments in order to be met. Reduction in maintenance investments may increase the rate of rail degradation, which may increase the risk of derailments.
At the same time large span or segmental bridges and tunnels, which are important parts of rail systems are particularly susceptible to deterioration with increasing risk of failure due to often harsh and aggressive environments, in combination with aging and increasing traffic load.
Evidently, efficient risk management and maintenance strategies of complex rail systems, which are based on fast and reliable inspection methods, can reduce significantly potential risks and cost. In Europe and other developed parts of the world, there are a lot of SMEs working with modern
technologies in the field of Non Destructive Monitoring of the performance of rail infrastructures. In spite of continuous efforts made by all rail organizations and relevant Non-Destructive-Testing (NDT) companies, detailed knowledge of methodologies and testing techniques has not kept pace with the development, as in both cases engineers have struggled to keep abreast with the increasing complexity of the applied methodologies. Because of this, testing quality and interpretation of results have suffered, compounded on occasion by insufficient knowledge of such specialized techniques by both applicants and supervisors of works. Even more, appropriate advice for necessary maintenance actions is not readily available being spread amongst many different specifications and references some of which outdated.
The overall aim of DIAGNO-RAIL is to develop an integrated system of state-of-the-art NDT methodologies based on multiple expertises improving risk assessment and failure prediction concerning the integrity and functionality of main track components and rail infrastructures in favour of the participating SMEs.
In particular precise Visual and advanced Magnetic Detection methods, for fast and reliable assessment of track failure and damage will be combined with state-of-the-art Acoustic methods, and Nuclear Magnetic Resonance (NMR) portable devices appropriate for examining the performance of concrete structures, in order to gain critical information concerning the performance, damage risk, and condition monitoring of rail and subway systems. In parallel,
advanced methodologies such as infrared thermography, and half cell potential will be applied, while an innovative chemical tool kit will be developed for in situ chemical analysis measurements, in combination with established modern analytical techniques, for civil construction materials characterization.
In the above framework the following S&T objectives have been set:
(i) The development of a set of methodologies for monitoring integrity, damage, and failure of track components.
Specifically:
1. A system of high definition camera fixed on a rolling vehicle associated with a high speed acquisition system and fitted floodlighting for complete image monitoring of the track is implemented. The image monitoring will be continuous up to the speed of 70km/h. The determination of optimum conditions for reliable continuous image monitoring of the track up to the speed of 70 km/h and a set of at least 10 000 reliable images is a measure for the meeting of the
objective.
In particular, an autonomous imaging hardware including high-speed high-definition camera with synchronized lighting and high-speed, high-capacity image acquisition and storage system developed by Alcon Diaz Consulting. This device can be embedded in any railway vehicle providing 500 W, 230 V AC supply. It provides continuous image monitoring of the track with inspection speed up to 70 km/h. More than 90 000 images were acquired during the project and more than 13 km of railway track were successfully inspected during real-scale field tests.
2. A fast image processing software will be developed and used for rail integrity verification, rail geometry measurements, switches and crossings location and condition, rail attachments monitoring, sleepers condition, ballast quality control, dilatation joints displacement measurements.
The measures of the successful completion of this objective include:
- identifying and localising principal components of the track (switches, crossings, dilatation joints, signalisation equipments); characterizing the geometry of the rail;
- measuring displacements of dilatation joints concurrently with temperature measurements of the rail;
- identifying the rail-sleeper attachments and sleepers condition;
- characterizing the mean size of the ballast aggregates.
In particular, an extended image processing software developed by the University of Cergy-Pontoise including various functionalities. Its first function is the generation of panoramic reconstruction of the track by stitching the series of successive images of the track acquired by the autonomous imaging hardware. Panoramic reconstruction of the track is the essential tool for safe, accurate and economic visual inspection and control of the state of the main components and devices of the track. Using processes of forms recognition, customized algorithms, specific criteria and thresholds, the image processing software includes additional functions with the aim of controlling the whole railway track, identifying critical defects and providing hard core information for risk management and maintenance strategy to the railway companies. These additional functions concern the automatic identification of sleepers on panoramic images, the automatic measure of the distance between adjacent sleepers, the automatic identification of the presence or the missing of bolts and screws and the measure of the aperture of thermal expansion devices.
3. A novel method for the magnetic detection of cracks in rail tracks based on the measurement of the magnetic induction of the surface of rails, by an appropriate array of magnetic field sensors (magnetic detection device).
The measure of the meeting of the objective includes complementary NDT methodologies such as Eddy Current and Ultrasonic methods which will be used to test the reliability of the proposed methodology.
4. Appropriate software for the magnetic detection device. The measures for the successful completion of the objective include:
- The software must communicate with the array of the magnetic sensors
- The software must be able to store multichannelly the data from the array
- The software must be able to identify cracks by analyzing the input data
(ii) A set of methodologies for monitoring integrity, damage, and failure of concrete components of rail systems will be developed.
5. Design and development of the FK microseismic methodology for monitoring condition and degradation of concrete structures. The measure of the meeting of the objective includes the correlation of the developed methodology with existing UT and Sonic methods for concrete components.
6. A user-friendly software package for non-experts in the microseismic FK method. The measures for the successful completion of the objective include:
- The software must communicate with the array of the microseismic sensors,
- The software must be able to store multichannelly the data from the array,
- The software must be able to apply a two-dimensional fast Fourier transformation (FFT) and to solve the Inverse problem by extracting the modes of Lamb and Rayleigh waves automatically with appropriate adjustments of the initial parameters.
7. The development of a unilateral NMR sensor and a portable NMR equipment for studying microstructure characteristics of mortar and concrete. The measure of the meeting of the objective includes the comparison of the data of the portable NMR devise with corresponding data from laboratory NMR experiments on reference samples with well known microstructure characteristics.
8. A user-friendly software package for non-experts in the NMR spectroscopy. The measures for the successful completion of the objective includes:
- The software must be able to record NMR signals from the portable sensor,
- The software must be able to apply a one-dimensional fast Fourier transformation (FFT) and implement pre-defined NMR pulse sequences.
9. Development of an innovative chemical tool kit for in situ chemical analysis of the concrete structures and market implementation. The measures for the successful completion of the objective includes:
- Ability to identify the chemical properties according to each type and category of deterioration agents which affect the subway concrete structures.
- Ability to identify different types of deterioration patterns.
All the above will be correlated with laboratory measurements on reference samples.
(iii) The Magnetic, Microseismic and NMR devices will be evaluated at Laboratory level.
10. Magnetic laboratory measurements on prototype specimens with predefined defects. The measure of the meeting of the objective includes the comparison with standard NDT tests such as Ultrasonic and Eddy Currents.
11. Microseismic laboratory tests on specimens made of concrete and mortars with controlled porosities, permeabilities, impurities and defects. Compositional characteristics and microstructure properties of the specimens will be examined with conventional laboratory techniques such as Electron Microscopy, Nitrogen and Mercury Porosimetry, Strength Measurements, Ultrasonic, etc. and compared to the microseismic and NMR data. These actions constitute the measure of the meeting of the objective. Specifically, a state of the art microseismic technique will be developed for the investigation of the mechanical properties of concrete using the acoustic module developed in the DIAGNO-RAIL proposal. The level of damage will be inferred by acquiring a seismograph of the concrete specimens, after a mechanical impact at low frequencies. The analysis of the seismograph will be carried out by taking in consideration higher-modes of surface wave propagation, including Rayleigh waves, Lamb waves- both symmetrical and antisymmetrical. This will result to a high resolution mapping of the corrosion versus depth profiles in concrete structures, currently unavailable with standard acoustic methods.
12. NMR laboratory measurements for the determination of moisture content, and the determination of the pore-size distributions in the materials. Standard NMR protocols will be employed. Results obtained from the portable device will be directly compared with the ones obtained from standard laboratory NMR equipment. The above actions constitute the measure of the meeting of the objective. Pore size distributions will be measured with NMR relaxation time measurements, to be carried out using standard NMR equipment and the relevant DIAGNO-RAIL portable device. Moreover, by implementing an inverse Laplace transform, it is possible to deduce pore size distributions from NMR results both at laboratory and on-site. The advantage of the NMR method
is that it allows on-site assessment of the porosity without the need of the expensive transportation of the core samples.
(iv) "On site" measurements with the developed systems will be performed in a rail system.
"On site" measurements with the developed systems were performed in a rail system.
RATP (Régie Autonome des Transports Parisiens) disposes a special carriage for railway inspection of the network. RATP provided free access to the special carriage, where the autonomous imaging hardware was embedded and tested on the RER A line in the Paris region.
Urban Rail Transport S.A. (STASY S.A.) in Athens, Greece, a company incorporated the three rail companies that existed from: AMEL S.A (attiko metro system operation), ISAP S.A (urban rail), and TRAM S.A. (tramway) accepts also to provide access to its railway network for on-site
measurements with the proposed methodologies. These two railroad companies will not be involved whatsoever in the development of the project and will be restricted of access to the know-how of the project and technologies involved.
13. The image monitoring device was performed on 13.650 km of the RER A line between the railway stations of Vincennes and Noisy-Champs at the East of Paris. This railway line is the most frequented of the Paris region with about 1500 trains and 650 000 passengers per day. The field testing allows the verification of:
- the continuous image acquisition and storage processing of images at the inspection speed of 70 km/h covering completely the inspected railway track,
- the adequate quality and definition of images for accurate identification and controlling of the main components and devices of the track,
- the high quality panoramic reconstruction of the inspected railway track and the efficiency of quality control indicators,
- the full automatic identification of sleepers and their localization on the panoramic images of the track
- the accurate automatic measurement of the distance between adjacent sleepers
- the automatic identification of fastening elements on the sleepers and the automatic detection of missing fastening elements
- the accurate measurement of the aperture of thermal expansion devices
- the easiness of use of the extended image processing software and the efficiency of its user guide.
14. On site magnetic crack detection. The condition of rail tracks will be examined in detail. The field implementation of magnetic crack detection and visual detection both placed in a fast moving vehicle will allow the correlation of these two different methodologies. Well established methodologies i.e. eddy current and ultrasound testing will also be performed and the overall aim is to develop a reference database of known track failures and how they are detected by magnetic crack and visual detection in contrast with eddy current and ultrasound testing.
15. The condition of tunnels, bridges, and other structural components of a rail system will be examined and monitored in detail. The advanced methods based on the portable microseismic and NMR devices will be applied on – site on the concrete structures of the rail system. The microseismic method will be assessed in real concrete geometries where higher – modes of surface waves propagation are of critical importance in the analysis of the deterioration profile of the structures and will provide information with respect to the in depth internal integrity of concrete as well as near-surface cracks and materials quality. The measure of the meeting of the objective include comparative field tests on the same rail structures, by applying existing state-of-the-art methods (like advanced IR-Thermography, Electrical Resistivity, Half Cell Potential).
16. The NMR portable device will be used for the on site evaluation of the porosity of the concrete structures in the rail system. An innovative aspect of this project is to perform on site determination of the pore size distribution of core samples extracted from the concrete structure. The measure of the meeting of the objective includes measurements and additional standard tests (IR Thermography, Electrical Resistivity, Half Cell Potential).
All undertaken actions aim (i) to give the partners a competition advantage in the relevant NDT Market (primarily NDT activities concerning maintenance and risk assessment of rail and subway systems in Europe), and (ii) to give an impulse to the academic partners to further develop and promote their applied research in the relevant NDT field.
Project Results:
Within the framework of the DIAGNO-RAIL project the main S & T results/foregrounds are presented below:
1. Portable Magnetic Detection Device
2. Software and User Guide for the Portable Magnetic Detection Device
3. Development of advanced image processing software for visual inspection of rail tracks
4. Extension of advanced image processing software with risk management and maintenance strategies criteria at laboratory scale
5. Development of Portable microseismic device and FK methodology
6. Laboratory Assessment of portable microseismic device. Report on comparison with other methods
7. Development of portable NMR device and methodology
8. Laboratory Assessment of Portable NMR device. Report on comparison with other methods
9. Chemical tool kit and User Guide. Report on Lab and work-site tests
10. Field Evaluation Report for Magnetic Detection device.
11. Field Evaluation Report for the Image Monitor Device in real conditions
12. Field Evaluation Report for acoustic device.
13. Field Evaluation Report for NMR device.
The main features and goals of each project results are described as follows:
1. Portable Magnetic Detection Device.
The objective of this result is the fabrication of a low cost portable device capable to detect cracks, from the magnetic field produced around a crack (stray magnetic field), in a magnetized rail track. The main specifications of the system for the magnetic detection of cracks are the following:
i) Use of GMR sensors as sensors of the field changes caused by the presence of cracks near or on the surface of rail tracks. GMR sensors appear to be the best choice due to their high sensitivity.
ii) Simultaneous real time acquisition of the voltage output signals, produced by an array of GMR sensors, by use of a data acquisition device/PC-card (in short DAQ) connected to a portable PC. It is estimated that it will be sufficient to use a DAQ with the capability of simultaneous acquisition of the signals of up to eight GMR sensors.
iii) The DAQ should be capable of supplying the bias voltage, which is of the order of 10 Volt, needed for the operation of the GMR sensors.
iv) Signal recording and signal analysis of the voltage output signals VOUT of the GMR sensors by the LabVIEW based data acquisition and analysis software running on the PC.
v) Simple self-contained apparatus of small size and low weight for portability.
The development of the portable magnetic detection device consists of an array of magnetic field sensors and a device for magnetization of the rail tracks.
The choice of the main components of the device is real important for the efficient utilization of the system. After a though investigation and a series of experiments the portable magnetic detection device was designed and fabricated successfully consisting of the following main components:
a) Part of the detection device that moves on top of rail tracks:
The moving part of the detection device consists of a magnetic circuit, used to magnetize the rail tack, and the GMR sensors, used to detect the longitudinal component of the magnetic field caused by the presence of cracks:
Magnets: The magnetization of the non-magnetized steel of rail tracks is a crucial step, in order to produce a magnetic field inside it and in external space near it. The abrupt changes in the components of this field, which occur near cracks that exist in rail tracks, form the basis of crack detection. It is necessary to generate magnetic fields of a few kGauss inside rail tracks, in order that the sharp voltage peaks produced by the sensors can be clearly distinguished from electronic noise. Magnetic fields of a few kGauss can easily be generated by relatively small electromagnets. Alternatively, it is possible to use permanent magnets which produce a magnetic field of a few kGauss, like ferrite magnets. Figure 6 shows the assembling of a magnetic circuit consisting from three rectangular pieces of magnetically soft steels (see Figure 6(b)) and two ferrite permanent magnets (SrFe12O19 magnets of Figure 6(a)). The permanent magnets are magnetized perpendicular to their lengths. The magnets of Figure 6(a) and the steel pieces of Figure 6(b) are assembled on the plastic skeleton of Figure 6(c). The result is shown in Figures 6(d) and 6(e). The side shown as upper side in Figure 6(e) is the one that will carry the GMR sensors and will be in contact with the rail tracks during crack detection.
GMR sensors: The GMR sensors that were chosen were the AA and AB series Analog Magnetic Field Sensors of NVE Corporation. More specifically, for the preliminary tests of the detecting device, the GMR sensors that were used were four sensors of the AA002-02 type with field sensitivity 3.0–4.2 mV/(VOe). Figure 7 shows the final form of the part of the detection device that moves on top of rail track: Figure 7(a) shows a general view, while Figure 7(b) shows specifically the printed board with the four sensors fixed on it. On the printed board are also fixed five coaxial cables with BNC connectors: one for the input biasing voltage of the GMR sensors and four for the output voltage signal VOUT produced by them due to the presence of longitudinal component of the stray magnetic field.
b) DAQ for collection of analog signals from GMR sensors and A/D conversion:
The analog voltage signals produced by the GMR sensors are collected and processed by a commercial data acquisition device (DAQ) purchased by “National Instruments”. The type of the device is “NI USB-6212 BNC” (see Figure 8) and is capable of collecting and digitizing 8 different analog voltage signals (16-bit, 400 kS/sec). The particular model incorporates a voltage source used to polarize the GMR sensors and can be connected to a PC through a USB port.
c) PC with data acquisition and data analysis software
The final component of the detecting device is a LabVIEW based software running on a portable PC. The software is designed to collect the digital signals produced by DAQ, store the signals to a hard disk and perform signal analysis for the detection of cracks.
2. Software and User Guide for the Portable Magnetic Detection Device.
The objective of this result is the development of user friendly software necessary for the proper operation of the magnetic detection device that is used for the magnetic detection of cracks on rail tracks. The developed software is based on the LabVIEW 2009 application. This application is capable: (a) of controlling all the parameters of the measuring process, such as biasing voltage VB and sampling frequency fS, and (b) for simultaneous real time acquisition of the voltage signals of the GMR sensors. This real time acquisition involves the control of the sampling frequency, of the analog-to-digital (A/D) converter integrated in the DAQ device, by the developed software. A reasonable choice for the needed software is to develop a LabVIEW based application, which is used for communicating/controlling the DAQ device.
Within the framework of the project a user friendly LabVIEW based software is successfully developed that allows the user to easily adjust the values of all the parameters that are relevant to the measuring process, through an easily understandable graphical user interface (GUI). The application of the software is mainly the communication between the PC and the DAQ device, the adjustment of all the parameters that are relevant to data acquisition and the testing of the data acquisition process in laboratory conditions. Based on tests made on rail tracks, where we have deliberately created cracks on their surfaces in order to test the device, we can argue that the instrument is capable of detecting cracks on rail tracks by measuring the changes caused by these cracks on the magnetic field produced inside the tracks.
3. Development of advanced image processing software for visual inspection of rail tracks.
The objective of this result is the development of an image processing software that is able to generate a panoramic image of the track by stitching series of successive images with varying degrees of overlapping. The panoramic image of the track is an essential tool for safe and accurate visual inspection and control of the state of the main elements and devices of the track (rails, joints, connections, attachments, sleepers, ballast, crossing and thermal expansion devices).
The advanced image processing software is successfully developed to stitch sequences of overlapped images and to provide continuous panoramic image of the track. This software includes powerful algorithms free from random movements of the camera during image acquisition and variable conditions of lighting. The panoramic image generation is a result of great number of key-points detection, key-points matching, image blending and image merging using a transformation estimates from one image to another based on four parameters: longitudinal translation, lateral translation, rotation and scale. On the other hand, computing time is incompatible with real time processing of images. Further developments have been performed from panoramic image of track. Firstly, the measurement of characteristic distances of thermal expansion devices which is essential for functioning control. Secondly, the automatic detection of the presence or absence of main elements of the track (anchor bolds).
4. Extension of advanced image processing software with risk management and maintenance strategies criteria at laboratory scale.
This result concerns the extension of the image processing software to the monitoring of rail track main defects for risk management and maintenance
strategy. Using forms recognition and including specific criteria and thresholds, the extended image processing software is able to control the rail integrity, to identify sleepers, and connections to control the presence of bolts and screws, to measure distance between sleepers and aperture of thermal expansion devices and identify main defects. Consequently, the extended image processing software provides all necessary information for the development of a decision making system for risk management and maintenance strategy.
In particular, the extension of the advanced image processing software provides full automatic monitoring of the track’s components and detection of their main defects using powerful algorithms. Moreover, the extended image processing software provides precise image of the current state of the track’s components that could be compared with the previous states and supply information about the progressive wearing and the aging of components and evolving of low risk defects. All this information is the essential input for a decision-making system for risk management and maintenance strategy and scheduling.
Risk management analysis is based on assessment of the consequences resulting from nonintervention on the component or the defect. For each intervention the risk’s frequency and the risk’s gravity have to be quantified with the aim of determining a global risk index evaluating the risk taken from non-intervention on the railway track. The value of global risk index is the main tool for risk management of the rail track and determines the priority of the intervention.
Moreover, the maintenance strategy for every reference period could be established on the base of a matrix of the values of global risk index for the components of the rail track and the interventions for each component, using adequate thresholds.
5. Development of Portable microseismic device and FK methodology.
This result involves the implementation of the microseismic FK method at frequency range 1-40 kHz for analysis and assessment in the weathered or delaminated concrete. The implementation of the method includes the assembly of appropriate modules, the accelerometers arrays, the impact hammer in one portable unit along with a preliminary software capable or acquiring the microseismic signals and analysing them according to the FK methodology.
The characteristic of the current seismic methods is that they operate at low frequencies (5 kHz - 60 kHz) making them suitable of yielding small strain mechanical modulus as a function of depth in concrete structures. The Innovation of the proposed microseismic method concerns the implementation of an advance signal analysis that takes into account the different surface waves that are produced in a confined geometry of real concrete structures (Lamb and Rayleigh waves) and solves the fundamental and higher-order modes of such surface waves. The method resolves fundamental and higher-order modes of both Lamb and Rayleigh waves to accurately evaluate concrete quality with depth.
The objective of this result is the implementation of the FK methodology in a state of the art, portable device, assembled from acoustic modulus. This device, in conjunction with the advanced signal analysis is used for in-field microseismic measurements in weathered or delaminated concrete. The main specifications of the FK device are the following:
i) Synchronization of up to five accelerometers for real time acquisition of acoustic signals in order to record a seismograph of over 16 instances. Synchronization is a critical part of the whole process, especially between the various sets of the five signals.
ii) Correlation of the impact hammer signal with the trigger of the accelerometers. The generation of the acoustic signal by the impact hammer must be correlated to the trigger of the accelerometers for synchronization issues and for the automated process of the data files.
iii) Signal recording and signal analysis.
iv) Simple self-contained apparatus of small size and low weight for portability.
For the development of the portable, microseismic device with the above specifications, a selection of state of the art acoustic modules is performed. The assembly of the modules is designed in order to achieve minimum volume of the final device for best portability. Thus, the main components of the developed FK microseismic device are the following:
a) A/D converter – Current stimulator
The A/D conversion of the data is based on a National Instrument PC card capable of driving eight accelerometers while also providing the current stimulation to them prior to trigger. The developed software allows the simultaneous recording and display of sets of data from up to seven accelerometers.
b) External Trigger
Triggering is accomplished in two ways depending on the experimental needs.
- The signal from the impact hammer triggers a circuit that generates a TTL pulse. This pulse is driven to the external trigger jack of the National Instrument PC card which drives the accelerometers.
- The signal of the impact hammer is driven to the channel 0 of the National Instrument PC card which drives the accelerometers.
c) Impact hammer
The impact hammer is a PCB piezotronics instrument. The hammer has several different impact tips in order to modify its frequency response and additional weight module. The frequency response of the impact hammer has a Gaussian like shape and its signal can be recorded via a BNC jack.
d) PreAmplifier
The pre-amplifier is used to amplify the signals from the accelerometers. The use of pre-amplifier is optional, depending on the experimental conditions.
e) Accelerometers
The accelerometers are from PCB piezotronics and are high sensitivity ceramic shear accelerometers with resonance frequency up to 50 kHz.
f) PC
The PC is a National Instruments PC mounted in a PXI-1002 rack along with the microseismic card. The whole system is portable and lightweight.
A state of the art, portable, FK microseismic device, is developed and implemented successfully. Based on the preliminary tests of a floor concrete sample we can argue that the instrument will be capable of measuring the mechanical parameters of concrete structures as well as to estimate their thickness.
6. Laboratory Assessment of portable microseismic device. Report on comparison with other methods.
The objective of this result involves the laboratory assessment of the the capability of the FK microseismic device and methodology by using
laboratory test specimens with different compositional characteristics, such as porosity and defects. As a result the advantages and limitations of the techniques and instruments developed and presented in result 5 are evaluated and validated at laboratory level for the specific materials. In addition, complementary NDT techniques together with strength tests have been used at laboratory level for the assessment of the device.
In order to evaluate the microseismic device a series of concrete samples were fabricated. These samples vary on composition and induced defects (from thermal treatment) and were fully characterized by standard methods (compressive strength, ultrasonic and impact echo measurements). In addition, two concrete walls with different thickness were tested and carrots were extracted to conduct strength measurements.
The main issues that were addressed during the laboratory evaluation of the microseismic device were the standardization of the experimental parameters. Specifically, we conducted experiments to determine the optimum experimental parameters for:
a. the trigger method
b. the best coupling of the accelerometers to the concrete wall
c. the initial distance of the impact from the array of accelerometers
d. the weight of the impact hammer in relation to the desired excitation frequency range
e. the distances within the array of the accelerometers.
f. Multichannel method and FK method.
Thus, the FK microseismic device is evaluated and validated successfully. Specifically, the device is tested on concrete samples and on test walls. By a series of experiments and testings the experimental procedure is finalized. The results from the conventional methods (impact echo and acoustic measurements) confirmed the results of the microseismic device within accepted deviation. The experiments on the test walls validate the capability of the device to measure and detect crucial parameters of the structures like the thickness and the mechanical characteristics (Poison ratio, Young modulus).
7. Development of portable NMR device and methodology.
This results involves the development of an NMR sensor, which is adjusted in portable NMR equipment for studying microstructure characteristics (specifically the pore size distribution) of stone, mortars, concrete, and other materials. The 1H NMR method has the advantage that it is a fast, non-invasive technique, capable of monitoring the microporosity in real time. The development of the instrument includes the design and construction of the magnet and the coil for the investigation of core samples extracted from the concrete structure. The innovation of the probe developed is determined by its capability to assess on site the porosity and the pore size distribution of water saturated core concrete samples extracted from concrete structures.
The objective of this result is the implementation of a state of the art, portable, solid state NMR spectrometer, assembled from solid state electronic modulus. This spectrometer, in conjunction with a portable permanent magnet is used for in field NMR measurements of core drilled samples. The main specifications of the NMR spectrometer for these particular experiments are the following:
i) Low applied magnetic field in order to reduce magnetic susceptibility differences between the solid phase and the fluid filling the pore space in NMR experiments in porous materials. These differences lead to field inhomogeneities inside the pore space, often called ‘internal gradients’ and can affect NMR measurements in various ways.
ii) High signal to noise ratio and fast recovery for the detection of the weak NMR signals with short relaxation times encountered in the NMR experiments of porous materials and particularly of core drilled samples which contain many paramagnetic impurities.
iii) Simple self-contained apparatus of small size and low weight for portability.
For the development of the portable, solid state broadband (2 – 800 MHz) NMR spectrometer with the above specifications, a selection of state of the art solid state electronic modules is performed. Subsequently, an assembly of the modules is designed in order to achieve minimum volume of the final spectrometer for best portability. The main components of the developed NMR spectrometer are the following:
a) Transmitter Section
The transmitter section is the part of the spectrometer that generates the radiofrequency (rf) needed for pulsed NMR. It consists of rf synthesizer, phase shifter and gating circuits, and rf amplifier.
b) PC based programmable pulse generator
The pulse generator is based on a National Instrument PC card capable of producing pulses with a minimal duration of 0.6 μsec. The software for the programming allows the design of pulse sequences including the specification of the number and the duration of the pulses, the intervals between them, their repetition time, etc.
c) RF synthesizer
The rf synthesizer is a radiofrequency source (10 kHz – 1000 MHz signal generator) which produces a stable frequency which can be set precisely and can be readily controlled by the computer interface. It creates the frequency signal for the spectrometer and is usually at a low level (a few mW).
d) The pulse gate
The signal from the synthesizer is controlled by a pulse gate. The pulse gate is a fast switch which is opened at defined moments to allow the production of rf pulses. We have used a series of broadband rf switches and phase shifters (DC – 5 GHz, Mini Circuits) which create the rf excitation pulses with certain phases, durations etc., controlled by the PC based programmable pulse generator.
e) Power amplifier
The power amplifier is used to amplify the rf excitation pulses. The amplifier (Tomco Technologies) is broadband within the frequency range 0.5 – 150 MHz, capable of supplying 250 Watts at the desired frequency of operation. The amplifier operates in class AB and is designed for pulse and continuous wave applications.
f) Duplexer
The signal from the power amplifier is guided to the probe head. The returning spin signal is directed to the preamplifier. The duplexer directs the strong rf pulse from the amplifier into the cable leading to the probe and not into the sensitive signal detection circuitry. On the other hand, it diverts the weak signal coming from the probe to the receiver section. We used a home made duplexer based on the impedance mismatched effect in the λ/4 circuit (CLC-π-circuit, λ is the wavelength).
g) Tank circuit in the probe head
The probe circuit is a tuned LC circuit, impedance matched to 50 ohms at the resonant frequency for efficient power transmission to the sample. The inductor L in the circuit is the sample coil, which is connected to ground at each end through tunable capacitors Cpar and Cser, to allow frequency and impedance matching. Power in and signal out pass through the same point on the resonant circuit, so that both the power amplifier and the signal preamp have a properly matched load. Between the power amplifier and the probe there is a pair of crossed diodes which shows high series impedance when the transmitter is off and low impedance during the pulses.
h) Receiver Section
The receiver section is where the NMR signals are detected and processed. It consists of preamplifier, quadrature receiver, and analog to digital converter.
i) Preamplifier
The preamplifier amplifies the weak NMR spin signal and sends it to the spectrometer. The preamplifier is a high-gain, wide-band module (5 – 600 MHz, 67 dB gain, 1 dB noise figure, MITEQ Inc.), which allows to achieve the necessary level of amplification of the NMR signal in one stage. Antiparallel diodes are set to the ground before the preamplifier to prevent damage on it through extruding remnants of the pulse. In this way voltages over 0.6 V are absorbed.
j) Receiver
The receiver utilizes two Mini Circuits (33 dB gain) amplifiers as gain stages. Dual phase-sensitive (quadrature) detection is accomplished directly at the NMR frequency without any intermediate conversion stages, using Mini Circuits mixers, splitters and a quadrature hybrid. Specifically, the signal after amplification is directed to a Mini Circuit splitter and the two signals are subsequently feed to two mixers (Mini Circuits) where they are mixed with two 90 degree out of phase reference signals coming out from the frequency synthesizer.
k) Analog-to-Digital Converter
The demodulated NMR signals are directed to low pass filters (pass-band DC- 1.9 MHz) and then are digitized using a two port National Instrument analog-to-digital ADC converter card interfaced with the computer.
l) Assembly of the system
Using the electronic units associated with the spectrometer, the assembly of the modules was performed according to the minimum volume design The assembly is arranged in three different layers and a very small volume has been achieved using as short rf cables as possible.
The portable broadband NMR spectrometer was coupled to a circular Halbach array magnet, which provides a uniform field in a compact format.
The implementation of a portable, pulsed solid state NMR spectrometer is successfully completed. The spectrometer is assembled from up to date solid state electronic modulus. The instrument allows the performance of NMR experiments in low external magnetic fields. The instrument exhibits good signal to noise ratio and fast recovery considering the low operational frequency. Finally the instrument is portable of relatively small size and robust. Based on preliminary laboratory tests we can argue that the instrument is capable of measuring the pore-size distribution of various saturated core samples of different origin.
8. Laboratory Assessment of Portable NMR device. Report on comparison with other methods.
This result involves the laboratory assessment of the portable NMR equipment. The main objective concerns NMR laboratory measurements on test specimens for the determination of moisture content, and the determination of the pore-size distributions of the samples. Standard NMR protocols are employed. Results obtained from the portable device are directly compared with the ones obtained from standard laboratory NMR equipment. In particular, pore size distributions are measured with NMR relaxation time measurements, carried out using standard NMR equipment and the relevant DIAGNO-RAIL portable device. Moreover, by implementing an inverse Laplace transform, it is possible to deduce pore size distributions from NMR results. The interpretation of the results contribute to the improvement of precision characteristics of the p-NMR. The advantage of the NMR method is that it allows on-site assessment of the porosity without the need of the expensive transportation of the core drilled samples. Composition characteristics and microstructure properties of the test specimens are also studied with conventional laboratory techniques and complementary advanced non-destructive techniques (NDT) are used at laboratory for the assessment of the device.
In order to evaluate the portable NMR device various test specimens were examined which were consisted of materials similar to the materials and structures mainly used in the railway system, e.g cement pastes, concrete, mortars and stones. The samples were examined in order to determine their pore-size distributions using conventional laboratory techniques and both laboratory and portable NMR instrumentation. The samples were prepared with different composition characteristics, microstructure and salt and water content.
The evaluation procedure of the portable NMR device includes three steps:
a) NMR laboratory measurements for the determination of moisture content, and the determination of the pore-size distributions of the test samples. The pore size distribution of the samples was measured with NMR relaxation time (T1) measurements using standard NMR equipment and the relevant DIAGNO-RAIL portable device. The experiments were carried out using standard NMR protocols, which included similar NMR probes, resonance frequency, pulse sequence and NMR parameters, acquisition program and data analysis procedures. The results obtained from both instrumentations were directly compared.
b) Conventional laboratory technique such as Mercury Intrusion Porosimetry was used to determine the pore-size distribution of the samples and validate the NMR measurements.
c) Complementary advanced NDT techniques were used at laboratory for the assessment of the device.
The laboratory evaluation of the DIAGNO-RAIL portable, pulsed solid state NMR spectrometer was successfully completed. The p-NMR instrument was capable of measuring the pore-size distribution of various water saturated samples of different origin. The NMR results obtained from the p-NMR device were directly compared with the ones obtained from the c-NMR device and it was shown that the data are in general good agreement. In addition, it was found the p-NMR relaxation time measurements were well correlated with the results obtained from the conventional MIP experimental measurements. Therefore, the p-NMR device is proven to be a reliable and valuable tool in determining the pore-size distribution and porosity of any given water saturated cementitious material.
9. Chemical tool kit and User Guide. Report on Lab and work-site tests.
The aim of this result is to develop all-in-one chemical kit for the in-situ qualitative and quantitative characterization of the most severe deterioration agents (e.g acidity, chlorides and sulphates, depth of carbonation), as well as, the development of an easy to apply methodology for the field surveys.
An extensive market analysis of available simple tests and microchemical kits, as well as portable instruments able to determine the nature of the ions/
salts and their concentration levels within concrete structures was carried out. On the basis of the above research and market analysis it was decided that the chemical kit must incorporates simple tests for semi-quantitative determination of water soluble ions, such as paper strips, microchemical and colorimetric kits by Merck, together with portable instrumentation, consists of a UV-Vis Photometer NOVA 60 A and a customized system using suitable pairs of Ion Selective Electrodes each time, for chloride, sulphate and nitrate determination.
The developed kit was based on the combination of the above suggested procedures. The kit was tested and calibrated in laboratory on test specimens prepared in collaboration with partner NTUA, with preset concentrations of chloride and sulphate salts, while additional effort was made in order to simplify the in-situ procedure and minimize the required amount of material sampled.
The on-site evaluation of the chemical kit was conducted in subway constructions (AMEL S.A (attiko metro system operation)) of the Urban Rail Transport S.A. (STASY S.A.) in Athens, Greece. For the monitoring of the penetration depth of chlorides into concrete lining of the tunnel samples were collected by drilling at different depths from the surface (5mm, 1-2 cm and 3-5 cm). Two different sampling areas of the concrete lining were selected bearing whitish
efflorescences, along with samples of whitish material from the encrustations and water samples from the inflows in the tunnel.
It was concluded that the results obtained both in laboratory and field applications are in good agreement with traditional laboratory tests and therefore it is concluded that the proposed chemical kit can be effectively used for routine monitoring of preservation condition and identification of risk factors in concrete structures.
10. Field Evaluation Report for Magnetic Detection device.
The aim of this result this result is the the field evaluation of the magnetic crack detection device in real work site conditions (a train station for example).
The field evaluation of the magnetic crack detection device was conducted at the railway infrastructures of “URBAN RAIL TRANSPORT S.A.” (or “STASY S.A.”) at Athens, Greece and the measurements showed that the instrument was capable of detecting defects in rail tracks by measuring the changes caused by these defects on the magnetic field produced inside the tracks
The capability of the instrument to provide accurate values of quantitative parameters that describe the geometrical characteristics of detected defects is still under investigation, but nevertheless it was quite obvious that the system was able to detect the position of cracks and defects by producing voltage peaks when it moved above them. The system was also capable of recording accelerations or decelerations of the cart of the detection device, which make the recorded signals more complicate but could possibly be used as extra information when it is not feasible to maintain the speed of the device at a constant value (for instance when moving the cart by hand).
11. Field Evaluation Report for the Image Monitor Device in real conditions.
This result involves the field testing of the whole image processing device in order to verify its efficiency for making automatic inspection of the railway track and providing critical input for risk management and maintenance strategy.
The field testing of the image monitoring device was conducted at RATP (Régie Autonome des Transports de Paris) one of the main French Railway Companies.
The image monitoring device was tested successfully in field conditions in the Paris region where more than 37,000 images were acquired from 13,650 km railway track and treated by the final version of the extended image processing software. 1,953 panoramic reconstructions of the railway track were produced by automatic image stitching.
The quality of the panoramic reconstructions of the railway track was evaluated by means of customized algorithms and specific criteria and thresholds implemented in the extended image processing software with the aim detecting any anomaly and providing reliable panoramic images.
The panoramic reconstructions of the railway track were used successfully for identification, detection and controlling of main track elements. Firstly, the sleepers were identified en their distance was measured for controlling any movement from their initial place in the track. Secondly, the fastening elements present on the sleepers and ensuring the mechanical connection of the rail with the sleeper were detected. More than 50,000 bold, nuts or screws
were controlled and lesser than 0.4% was identified as missing. With these results the field testing demonstrates that the image monitoring device is able to provide accurate and reliable critical information for risk management and maintenance strategy of the railway track.
Finally, using customized algorithms implemented into the image processing software, the image monitoring device can easily include new functionalities as the recognition and localization of main rail defects as for example, rail corrugation, splintering or lateral wearing providing complementary critical information for a making-decision system for risk management and maintenance strategy.
12. Field Evaluation Report for acoustic device.
This result involves the evaluation of the microseismic device in field conditions. The in-field measurements were conducted at the rail network of the Urban Rail Transport S.A. (STASY S.A.) in Athens, Greece. This company incorporates the three rail companies operating in Athens and include: AMEL S.A (Attiko metro system operation), ISAP S.A (urban rail), and TRAM S.A. (tramway). In particular, the in-filed measurements of the microseismic device were conducted in the concrete supporting plates of the rails at the rail system of AMEL (metro company of Athens). The field measurements were conducted at the rail network between the stations “Nomismatoskopio - Ag. Paraskevi” and between the stations “Holargos – Ethiki Amyna”, during the maintenance hours of the AMEL (from 01:00am to 04:30am).
The measurements were conducted in selected areas:
a. near the walkway,
b. besides the rails,
c. at the area below the third rail.
Furthermore, the measurements were conducted at selected points between the rail stations:
a. at points of high humidity,
b. at points of great rail curvature where the load on the cement plates is greater
c. and for reference purpose, at completely dry and straight points where the cement plates are expected to be intact.
All the results from the field measurements were consistent with the tunnels outline as provided from AMEL. We were able to detect the actual depth of the concrete support plates in most cases. We conducted measurements on sites where the cements plates are expected to be intact (at the entrance of the stations and below the third line) for reference purposes. We were able to detect deterioration of the concrete plates consistent with the environmental parameters (high humidity, great curvature).
Overall, the microseismic device was proven reliable in field conditions.
13. Field Evaluation Report for NMR device.
This result involves the field evaluation of the portable NMR equipment on concrete structures and in particular the capability of the NMR device in real work site conditions. The field measurements were conducted at the rail network of the Urban Rail Transport S.A. (STASY S.A.) in Athens, Greece. This company incorporates the three rail companies operating in Athens and include: AMEL S.A (Attiko metro system operation), ISAP S.A (urban rail), and TRAM S.A. (tramway). In particular, the on – site application of portable NMR equipment was conducted using core samples extracted from the infrastructure of the rail system of AMEL S.A (Attiko metro system operation). AMEL S.A. is a state company of high scientific training, which based on reliable scheduling and systematic work, implements the development of the Athens Metro network.
The field measurements were conducted at the rail network between the stations “Nomismatoskopio - Ag. Paraskevi”, and between the stations “Holargos – Ethiki Amyna”, during the maintenance hours of the AMEL S.A. (from 01:00am to 04:30am). Different samples were extracted from the building structure (tunnel, walls, etc) of the metro stations. These core samples were extracted from areas of the tunnel with increased moisture level, leakage of water and areas with salt efflorescence on the surface. The selection of these areas was mainly based initially on visual inspection of the concrete structures following a detailed thermographic survey for a full proof evidence for moisture presence beneath the surface.
The extracted samples were measured with the portable NMR equipment in order to evaluate the porosity of the samples and to determine on-site the pore-size distribution. The pore-size distribution of the extracted core samples was determined by measuring the T1 and T2 1H NMR relaxation times.
The NMR measurements showed that the instrument is capable of the on-site determination of the pore size distribution in defected concrete structures. It is proven that the evaluation of the pore-size distribution can provide an estimate concerning the integrity of such large scale structure and thus, the capability of the instrument to provide results in real work site conditions is established successfully.
Finally conventional state-of-the-art inspection techniques were used such as Infrared Thermography, Electrical Resistivity, Half Cell Potential, corrosion current density measurements in order to evaluated the preservation state of the similar railway tunnels measure above of the AMEL. From the diagnostic studies, it was deduced that infrared thermography can provide significant information about the moisture mapping providing real-time results in such types of inspections. In particular it can be used efficiently for the assessment of large scale concrete constructions as well as to disclose any subsurface features. On the other hand, Electrical Resistivity, Half Cell Potential, corrosion current of steel reinforcements and GPR provided information regarding the condition of the concrete structure and its corrosion gradient on regions where humidity was detected through the thermographic monitoring. These results from the inspection methods correlate very well with the results obtained from the field evaluation of the microseismic and NMR device.
Potential Impact:
The overall aim of the project is to develop an integrated system of state-of-the-art NDT methodologies to improve risk assessment and failure prediction concerning the integrity and functionality of rail systems, in favour of the participating SMEs and is divided in two main areas of application:
Inspection of Rails with precise Visual and Magnetic ac-Susceptibility methods and Inspection of concrete elements of the rail system with on site Acoustic, and Nuclear Magnetic Resonance (NMR) methods combined with a chemical tool kit for in situ chemical analysis measurements.
The main guidelines of the overall dissemination strategy are:
a) Development of awareness, transfer and publicity activities for the industrial and research communities, as well as for the general public.
b) Publications of scientific papers.
c) Organization of presentations and trials as standalone activities of the project or within relevant conferences in the area.
d) Design and production of publishing materials in both printed and electronic form.
e) Development and maintenance of a web site dedicated to the project.
f) Network and established distribution channels of the individual partners.
In the first reporting period, the following results have been achieved:
i) Selection of appropriate project logo
ii) Project Factsheet
iii) Project flyer
iv) Project presentation
v) Set up of the project website, maintenance of News section and other contents (public and members area, project repository)
At the end of the project the following dissemination activities were completed:
i) Conferences releases
ii) Published field results
iii) Promotional material forwarded to end-users
iv) Presentations to end-users
v) Update of the promotion material and the website
DIAGNO-RAIL logo
A logo for the DIAGNORAIL project has been selected and will be attached as a separate file in this report.
DIAGNO-RAIL Factsheet
The project Factsheet is a two-pages folder containing four sections: At a glance (with the main figures of the project), Overview, Challenges and Activities. The Factsheet will be attached as a separate file in this report.
DIAGNO-RAIL Flyer
The DIAGNO-RAIL flyer contains a title page, a page with all partners’ logos, the name and address of the co-ordinator. The other three pages contain an overview of the project, a description of challenges for each of the proposed methodologies of the project and characteristic images of the results (Figure 3). The Flyer will be attached as a separate file in this report.
DIAGNO-RAIL Web site
The DIAGNO-RAIL web site was established in two steps: at first only for internal use, then for public dissemination (http://www.ims.demokritos.gr/diagnorail). The home web page of the project includes general information about the project and the overall aim of the project. There are six different links available:
a) The Project
b) News & Events
c) Partners
d) Documents
f) Progress
g) Forum
“The Projects” link includes information about the main objectives of the project, the materials under investigation and the innovative methods which are used in the DIAGNO-RAIL project. Also there is a link to the European Commission CORDIS web site, where there is direct information about the funding sources, the project description, details and participants.
The “News & Events” link includes information regarding the news, press, events and meetings that will take place during the progress of the project. This section shares information regarding all the project activities that helps promote the DIAGNO-RAIL project. These activities include the published joint papers in peer-reviewed international journals and the presentations at international meetings and conferences. Moreover, all the review meetings between the partners are listed.
In the “Partners” link a description of the Consortium as whole is presented. The Consortium comprises of seven participants. The selection criteria of the specific seven participants for the completion of DIAGNO-RAIL project are given in detail. A general profile of each partner is presented with all the contact information and the name of the responsible person.
The “Documents” link includes the newsletter, publications, performance reports and file manager. These documents are important for maintaining communication with each partner, for promoting the DIAGNO-RAIL project to the public and also for promoting a wider use of NDT techniques in the field of railways and construction. In the “Progress” link there is detail information regarding the work packages, the tasks, the deliverables and the milestones of the DIAGNO-RAIL project. In this section tables and GANTT charts are presented showing each month the timing and status of the work packages, tasks, deliverables and milestones of the DIAGNO-RAIL project.
The “Forum” link is for communication purposes between the DIAGNO-RAIL partners and also it is a place where people discuss topics related to non-destructive testing, decision-making and policies. In particular, during the project, mailing lists will be requested from existing European networks or target groups related to the field of non-destructive testing, and will be prompted to register DIAGNO-RAIL’s portal. Workpackage leaders are responsible for disseminating the results of their respective Workpackage to the target groups. Target groups include professional organizations and Non-Destructive Testing Societies.
Conferences
DIAGNO-RAIL results were presented to the following International conferences.
1. ICNNAI'2012 - The 7th International Conference on Neural Networks and Artificial Intelligence
October 10-12, 2012
Minsk, Belarus
Scope of the conference:
The aim of the conference is to present and discuss research results and their applications, to support and accelerate world-wide exchange of ideas. The continuous exchange of scientific and technical information is of particular importance for the research and the transfer of research to practice. The scope of this conference covers the theory and application of neural networks and techniques of artificial intelligence. New techniques, instruments and both software and hardware components are included. ALCON and UCP contributed to the above conference with a paper:
"Railway track inspection using artificial vision"
A. Belhaoua, J. L. Gallias, N. Renault, V. V. Bui and P. Faucon
This contrition involved the visual inspection of the rail track using an advanced image monitoring method and an advanced image processing software for fast and reliable assessment of track failure and damage.
2. 12th International Conference on Recent Advances in Concrete Technology and Sustainability Issues
October 30- November 2, 2012
Prague, Czech Republic
Scope of the conference:
This conference includes topics in Advances in Geological CO2 Sequestration and Co-Sequestration with O2; Self-Compacting High-Performance Concretes; Dynamic Performance of Eco-Friendly Prestressed Concrete Sleeper; Parameters Influencing the Performance of Shrinkage-Compensating Concrete, and much more.NTUA contributed to the above conference with the following papers:
a) Corrosion Inhibitors and Macrogalvanic Cells.
G. Batis, E. Zacharopoulou, A. Zacharopoulou.
b) Novel Concrete Coating Materials: Physicochemical Characteristics and Performance Evaluation against Corrosion
Th. Zafeiropoulou, E. Rakanta and G. Batis.
This contrition involved the compositional characteristics and microstructure properties of concrete examined with conventional laboratory techniques. This activity was important as the conference was international involving people from around the world, which aids the promotion of build in this project.
All the above dissemination activities are important as all the conferences were international involving people from around the world and thus raise the public awareness with regards to the research work of the project, the achievements of the project and all these results to the promotion of the integrated system that was built in the DIAGNO-RAIL project.
Publications
DIAGNO-RAIL results were published under the following titles:
1. Railway track inspection using artificial vision
A. Belhaoua, J. L. Gallias, N. Renault, V. V. Bui and P. Faucon
This paper (6 pages) is a contribution from ALCON and UCP and was accepted and published in the conference proceedings of the seventh International Conference on Neural Networks and Artificial Intelligence.
2. Inspection of Railway Track Fastening Elements Using Artificial Vision
A. Belhaoua, J. L. Gallias, N. Renault, V. V. Bui and P. Faucon
This paper is a contribution from ALCON and UCP and is submitted to the international scientific review "Transportation Research" and is 23 pages.
The above dissemination activities are important as the publications give the opportunity to promote the DIAGNO-RAIL project to the general public through the internet given details about the capabilities of the developed methodologies as well as the direct and powerful applications.
DIAGNO-RAIL Presentations
A presentation of the DIAGNO-RAIL project has been developed in order to be addressed to an end-user network. It contains technical information for each proposed methodology of the project and the expected overall benefits. A comparison with the existing state-of-the-art methods is conducted and preliminary results are presented. This presentation was presented to the Urban Rail Transport S.A. (STASY S.A.) in Athens. Greece. This company incorporated the three rail companies that existed up to that point: AMEL S.A (attiko metro system operation), ISAP S.A (urban rail), and TRAM S.A. (tramway). The goal of this presentation was to present the concepts and capabilities of the project along with other promotional materials in order to establish a potential end-user interest for the DAIGNO-RAIL project. Thus, ENDITECH S.A (the coordinator) has managed to establish new contact and promote the developed technologies to STASY S.A. who showed a big interest and agreed to provide access to its railway network for the on-site measurements with the proposed methodologies, which include in-field test of the Magnetic Crack Detection Device, in-field test with the FK microseismic device/methodology and on – site application of portable NMR equipment.
Moreover, many contacts have been taken by Alcon Diaz Consulting and by the University of Cergy- Pontoise during the DIAGNO-RAIL project with three main French Railway Companies, as such as RATP (Railway network company of the Paris region), SNCF (French National Railway Corporation) and EUROTUNNEL (French-English railway company operating under the Channel) for making advertising about DIAGNO-RAIL project, and particularly image monitoring device, and for negotiating field testing with the higher impact. Finally, RATP (Régie Autonome des Transports de Paris) offered the best conditions for the testing, providing, as 2 years ago (see report of June 2011, deliverable 2.1) a special railway carriage for testing.
A demonstration of the DIAGNO-RAIL project was carried out at the STASY S.A site (metro company of Athens) and in France (RATP).
The dissemination and exploitation of project results is significant to DIAGNO-RAIL project. A final plan of the dissemination strategy of the DAIGNORAIL project was concluded and certain measures in the dissemination and promotion of project results were taken to diffuse the capabilities of the project to the different professional, political and social groups. The underlying goal of the dissemination plan was to promote the idea of maintenance and quality of public works into the society and to create links among researchers, end-users, and decision-makers.
List of Websites:
The official website of the project for the public awareness has been developed and the web page address is the following:
http://www.ims.demokritos.gr/diagnorail
The DIAGNO-RAIL web page is hosted at the Institute of Materials Science, N.C.S.R. "Demokritos", Greece. It is a dynamic web page, which can be modified by registered users. Furthermore, a file manager provides data exchange between registered users.
