Review of severe deformation recommended practice through analyses comparison of two cab car end frame designs

Non-linear large deformation analyses have been conducted to evaluate the performance of the cab car corner and collision posts of the Federal Railroad Administration's (FRA) sponsored state-of-the-art (SOA) end frame design and the Bombardier M7 design under quasi-static and dynamic test conditions. Pre-test analysis predictions of the dynamic performance of the SOA corner post closely match test measurements. A similar analysis of the corner post was performed on the M7 design, and the results compared with the SOA test and analysis results. Using this M7 model, analysis results for the quasi-static test of the collision post were developed, and compared with the test measurements. Up to the onset of material failure, the analysis results and test measurements closely agree. After the onset of material failure, the results progressively diverge. Overall, the crashworthiness performance of the collision posts of the SOA and M7 designs were found to be essentially the same, and the performance of the M7 corner post design was found to perform better than the SOA corner post design. This difference in performance comes from the sidewall support in the M7 design, which is not present in the SOA design.