Switches and Crossings
Steps toward a whole system model framework for switches & crossings have been taken. As an example of implemented results is the prediction of crossing geometry evolution (due to plasticity and wear) under operational loading. This modelling (which includes a multitude of numerical tools), allows a crossing design that (after a short time) "wears in" to the optimal geometry. This will significantly increase the operational life of the crossing. The economic benefit will depend on the operational conditions, the base case (e.g. the “unoptimized geometry” to compare towards) and local rates for maintenance and replacements including secondary costs.
It was found that opportunity exists to prevent a significant proportion of faults relating to switches by self-adjusting. The faults which remain, or are uneconomical to prevent, may be detected early using a range of sensing, which is mature in the railway industry. Automatic self-adjustment can be fitted to the majority of switches. A cost-benefit analysis of self-adjusting switches and crossing infrastructure with built-in monitoring, considered over the life-cycle of the asset indicating an 8% annual rate of return was performed in In2Track.
Track structure
Slabs with a twofold objective for the fibres has been developed. The first objective is as a traditional reinforcement. The second objective is to deteriorate the interface when replacement is necessary. In the case studied, the deterioration has been triggered by microwave application. The ability to deteriorate the slab provides a major benefit in required time and resources when a slab needs to be replaced; a slab that can be broken up by fibre debonding needs much less efforts for demolition. The related cost savings will depend on the local conditions of track, labour etc. They should be possible to estimate with rather good precision for specific conditions.
Building on work in In2Rail, a method for repair of discrete rail defects using line welding has been further investigated. In particular, the propensity for subsurface initiated rolling contact fatigue at the weld has been investigated in depth using numerical simulations. Through this simulation-based validation, the risk has been shown to be moderate, which makes the method suitable for implementation in field demonstrators. Due to its efficiency and reduction of operation time, the method was in In2Rail shown to be a cost-efficient method to handle severe rail surface defects. The research in In2Rail further confirms the potential of the method.
Structures
In2Track has investigated inspections using high definition images of tunnel lining paired with precise positioning, lidar scanning and an autonomous digital image correlation software capable of automatically detecting significant changes in the external aspect of the tunnel lining. Several test runs have been made in the project. The technology brings economic and capacity related benefits and also improvements in workers safety.
Optical measurement methods – ground based and un-manned aerial vehicle (UAV) mounted – have been used to test the applicability of several image-based technologies in the creation of digital twins, detection of damage and identification and tracking of changes in geometry and structural behaviour of bridges. In addition, trials using un-manned aerial vehicles for bridge inspections have demonstrated that the data is of improved quality compared to the traditional methods and provides sufficient information to the asset owners to assess the overall condition of the bridge. The benefits of these enhanced inspection methods include reduced traffic disruption, decreased costs and enhanced workers safety.
