Technical Reports

Conventional Passenger Rail Vehicle Safety, Volume I: Summary of Safe Performance Limits

  • 01
  • Sep
  • 1998
AUTHOR: G. Samavedam, J. Gomes, P. Warren, F. Blader
SUBJECT: Passenger Rail
KEYWORDS: Equalized and Non-Equalized Trucks, OMNISM, Computer Simulation
ABSTRACT: This report presents a methodology based on computer simulation that assesses the safe dynamic performance limits of commuter passenger vehicles. The methodology consists of determining the critical design parameters and characteristic properties of both the vehicle and the track, establishing the failure modes, and then using a computer model to determine under what conditions the failure occurs. The computer tool predicts the dynamics of the vehicles at varying speeds and safety limits and margins are established based on when the predicted behavior approaches a derailment. This report also presents numerical examples of this methodology that were produced using the software tool OMNISIM to predict the response of single and bi-level vehicles as they negotiate both tangent tracks and tracks with curves up to 20 deg. Imperfections such as cusps, misalignments, and switch points are simulated to determine conditions of unsafe vehicle behavior. Safe performance limits for the cars with assumed parameters are developed and presented in terms of maximum imperfection amplitudes and vehicle speeds.