Post-derailment dynamic simulation of rail vehicles – methodology and applications

An earlier developed multi-body system post-derailment module, that predicts the wheelsets’ behaviour after impact with concrete sleepers, is upgraded to account for possible wheel–rail fastener impact situations, after train derailments at high speed. The vertical stiffness describing the wheel–fastener impact behaviour is calibrated and validated based on two authentic derailment cases. Geometrical specifications that permit a brake disc and a bogie frame to act as substitute guidance mechanisms after flange climbing derailments on curved track are presented for an X 2000 trailer car. Further, an introductory analysis on the post-derailment vehicle behaviour on tangent track after a ‘flange on rail head’ derailment condition is also presented as a function of bogie yaw resistance. The risk of carbody overturning after derailments on tangent track is assessed as a function of coupler height and carbody centre of gravity as well as bogie transversal beam position.