Authors: David Tyrell, Kristine Severson

Date of Publication:  October 1996

Sponsoring Agency:  U.S. Department of Transportation - Federal Railroad Administration, Office of Research and Development

Performing Organization:  USDOT Volpe National Transportation Systems Center, Office of Systems Engineering

Report No:  DOT/FRA/ORD-96/08

Abstract:

Tests have been conducted on Amtrak's traditional passenger seat to evaluate its performance under static and dynamic loading conditions.  Quasi-static tests have been conducted to establish the load-deflection characteristics of the seat.  Dynamic tests of selected collision conditions have also been conducted with instrumented Hybrid III dummies to evaluate the collision performance of the seat and to verify the analytic simulation tools.  This report describes the results of the crashworthiness testing of Amtrak's traditional seats.

The quasi-static testing indicates that the seats are sufficiently strong to withstand the occupant loads predicted from the computer simulation.  However, in dynamic tests with a triangular crash pulse peak higher than 5 g's, the seat attachments are prone to failure, particularly at the wall mount.  The dynamic test failures were possibly due to the inertial effects of the seat, which were not present during the static tests.

Injury criteria measured and calculated from the dummies included Head Injury Criteria (HIC), chest deceleration, axial compressive neck load, and femur load.  The injury criteria for all seven dynamic tests were within the acceptable human tolerance levels as specified in standards by the National Highway Traffic Safety Administration (NHTSA) and the Federal Aviation Administration (FAA).

The dummy's head and chest deceleration time histories and injury criteria from the dynamic tests have been compared with the results of simulations corresponding to each of the seven dynamic tests.  These comparisons demonstrate a reasonable agreement between the analytic predictions and the dynamic test results, given the variability in the effective stiffness of the seats under different loading conditions.
 

No. of Pages:  80