Development of next generation guardrail systems using crash analysis and heuristic optimization methods

The guardrail systems are being designed to keep the vehicles moving in the traffic in the road and to reduce the risk of injury during an accident. The crash performances of these systems were determined with tests and simulations which were performed according to EN 1317 European Roadside Safety Standards. In this study, crash tests of a guardrail system, which has H1 containment level, were simulated and new designs were performed to improve the crash performance. Steel posts with different cross-sectional design, steel W-Beam, connection plates and bolts were used. Guardrail systems were designed with 25 different post sections with different design variables and the distance between the posts was designed as 2.00 m for the analysis. Three dimensional solid models have been prepared in CATIA while finite element models have been built up with HYPERMESH. TB11 and TB42 crash analysis were performed with RADIOSS software according to EN 1317 standards. 25 different designs were evaluated according to weight, guardrail's working width and acceleration severity index (ASI). 2 of 25 designs were found to be unsuccessful to keep the vehicles on the road during the collision, so excluding these models, the optimum design has been trying to obtained over 23 models with gravitational search algorithm, which is one of the heuristic optimization methods. As a result of optimization, an optimum design was obtained which has minimum weight and acceleration severity index value (ASI).