Objectif
In the definition phase of the project research was directed towards the requirements and design specifications for both demonstrators. The application areas for safety fences were defined as: Bends, bridges and fly-overs in secondary roads; for lighting columns: The 10 metre column was considered to offer the optimum contribution to passive safety.
Based on a survey of energy absorbing mechanisms a number of design concepts were developed. Using multi-body software Madymo and Vedyac impact behaviour of vehicles was evaluated, finally resulting in the choice for two demonstrators: a patented "Tilting Bird" system for the safety fence and a tapered 10 m Lighting Column.
For these kinds of applications materials and specific processes were developed and selected: pultrusion and sheet moulding compound technology for the safety fence and vacuum injection for the columns. Assessment of the applicability of thermoplastic materials for inclusion in the safety fence was also undertaken.
Safety fence:
The properties and requirements of safety fence components have then been defined in detail. Coupled with the evaluation of impact performance a material selection was made for each element of the safety fence.
The design of the overall geometry together with component geometry (beam and post) was completed using Vedyac, Madymo and FEM software. In depth analysis was conducted on the jointing techniques between all elements of the Tilting Bird system and as a result the dynamic behaviour of the connections were established.
Resulting from the dynamic impact testing on ground anchor and ground anchor post connection, the design of spacer and ground anchor was almost completed.
Two full-scale tests were performed according to the CEN standard prEN 1317. The test with the car (900 kg/100kph/20°) was successful and according to the simulations, however the full-scale test with a bus (13000kg/70kph/20°) was not successful due to local failure of the longitudinal beam.
Lighting column:
A Mathcad software tool was developed for the evaluation and design of composite lighting columns. Using FEM calculations the performance of columns under impact was evaluated. Six prototype lighting columns were manufactured of which two were full-scale tested (side impact 70 kph and frontal impact 100 kph) in accordance to the PrEN 12767 passive safety standard. The tests indicated that the initial design was too stiff resulting in higher than predicted decelerations.
As a consequence the column was redesigned and re-crash tested. This resulted in a partly successful full-scale frontal impact test. The outputs Revealed that LE3 passive safety performance has been demonstrated for a 100 kph frontal impact, which is the highest level of safety. However, further development is required to avoid secondary impact and reduce the damage to the vehicle.
Roadside safety systems need to be further improved to increase the safety in terms of vehicle occupant survivability and reducing injury levels. Accidents can be prevented by increasing the visibility of the current roadside safety systems and improving the visual guidance function of the current crash barriers. Besides, the leaching of zinc from steel guide rails (approximately 3000 tonne per annum in Europe) is one of the largest diffuse sources of heavy metal pollution. New advanced polymeric composite materials technology can come up with a favourable solution for the above mentioned problems. However. composite materials have remained prohibitively expensive and slow to penetrate other roadside safety equipment sectors. The major barriers to wider applications are: A lack of cost effective processing technologies.
A lack of composite impact performance data. A lack of appropriate composite design philosophy. A lack of composite modelling capabilities. With a concerted action, presented in this proposal, the development can be initiated and carried out successfully. The overall objective of the project is to improve roadside safety systems by the versatile use of fibre reinforced polymer composite materials in these systems. More specifically this project should lead to the development of roadside safety systems, which have the following benefits: Improved safety for all road users. Improved reliability, durability, maintenance and cost effectiveness based on a through life analysis. Improved safety and working conditions for road maintenance personnel. Lower impact on the environment during its life cycle than current steel systems.
More specifically the consortium will address the following objectives: To develop and demonstrate rapid and cost effective process technologies that will allow composites to compete with existing materials within 3 years. To develop an understanding of the behaviour of composite materials when impacted by high-energy loads within 3 years. To validate computer models which simulate the impact performance of errant vehicles on composite roadside safety equipment within 3 years. To develop and validate new composite design techniques which optimise energy absorption for use in roadside safety equipment within 3 years. The result will be 2 validated case study roadside safety systems which will be reviewed from a technical performance and economic competitive point of view. The proposed project is presented by a consortium whose partners cover a desirable range of material technologies (Scott Bader, EPL), manufacturing technologies (Decostone, EPL, Structil, Top Glass), composites design and modelling expertise (TNO, PTM), roadside safety expertise (PTM, Prof. V. Giavotto, chairman of CEN TC226/WGI), and installation expertise (Nevag) which could not be found in one country alone. Besides, the Project Advisory Board (set up in order to ensure the development of systems needed by the market and to aid exploitation) will consist of representatives of national road authorities.
Champ scientifique
Thème(s)
Appel à propositions
Data not availableRégime de financement
CSC - Cost-sharing contractsCoordinateur
1780 AM DEN HELDER
Pays-Bas