Structural Crashworthiness Standards Comparison: Grade-Crossing Collision Scenarios

In support of the Federal Railroad Administration’s (FRA) Railroad Equipment Safety Program, American and European grade-crossing collision scenarios were evaluated and compared. Finite element analyses (FEA) were employed to subject an FRA-compliant passenger car to grade-crossing collision scenarios defined in both the proposed FRA Code of Federal Regulations (CFR) and European Standard (EN) 15227. The proposed FRA collision scenario involved a single car impacted by a cart. The cart had a punch mounted to it to hit a specific post of the end frame of the car. The EN 15227 collision scenario involved a complete train consist impacting a large deformable obstacle that approximates a lorry. The analyses show that these collision scenarios, while both grade-crossing scenarios, are very different not only in terms of the impact object and the amount of initial kinetic energy involved, but also in terms of how the car is loaded and deformed during impact. The FRA scenario is shown to be easier to analyze as well as easier to test than the EN 15227 scenario. Additionally, the FRA scenario is safer to test because of the levels of initial energy involved. The FRA scenario also provides clearer metrics of success. The FRA-compliant car utilized in the analyses and test conducted for this paper passed both FRA and EN 15227 grade-crossing collision scenarios according to the requirements for each respective standard. However, the analyses show that despite both scenarios providing for energy absorption in a grade-crossing collision, because the manner in which the car is loaded and deformed (concentrated vs. distributed) is different, the FRA performance standard and EN 15227 grade-crossing collision scenarios are not equivalent and mutual compliance is not guaranteed.