Management of wheel/rail interface to prevent rail rollover derailments

Abstract

Recent rail rollover derailments motivated this investigation. The wheel/rail forces under seven track/rail conditions were measured at a curve of a heavy haul line. The investigation indicated that combinations of reverse rail cant, weak rail restraint, poor truck steering and poor wheel/rail contact can increase the risk of a rail rollover derailment. This investigation reaffirms the findings from previous rail roll studies and further stresses three important issues related to track maintenance practice. First, track maintenance tasks that involve changing track gage or rail orientation can have the unintended consequence of causing adverse wheel/rail contact, resulting in large lateral forces. Rail grinding should be coordinated with the restoration of rail cant to correct wheel/rail contact patterns. Second, restoring and restraining only the high rail has a high risk of causing a rollover derailment from the low rail. Third, rail grinding cannot be properly conducted on a track that has weak rail restraint and variable levels of reverse rail cant.