A SIMPLE DYNAMIC MODEL FOR SIMULATING DRAFT-GEAR BEHAVIOR IN RAIL-CAR IMPACTS

A new, simple dynamic model is developed for use in simulating draft-gear behavior in rail-car impacts. The model is based on an analysis of the individual components inside several types of draft gears. The transition from kinetic to static friction during the impact is included. Comparisons with drop-hammer tests and full-scale impacts show good agreement with the experimental forces and deflection. In particular two very important phenomena are correctly simulated: 1) the rise in force just before maximum travel, and 2) the stick-slip-grab phenomenon during impact.