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.

Analytical Nonlinear Modeling of Rail and Fastener Longitudinal Response

“…As discussed by Khachaturian et al ( 17 ), fastening systems, like many of the components in the rail infrastructure, have evolved iteratively over time, through a trial-and-error design approach aimed at addressing conditions symptomatic of track strength and force-transfer deficiencies (e.g., plate cutting, rail seat deterioration, rail rollover, rail pad movement) ( 18 ). These deficiencies have also led to various track component failures (e.g., broken spikes, broken shoulders, broken threaded rods) that have caused derailments ( 19–23 ). Between 1999 and 2018 there were 250 Federal Railroad Administration reportable derailments on mainlines and sidings in the United States caused by “defective or missing spikes or rail fasteners” ( 24 ).…”

A mechanistic model of lateral rail head deflection based on fastening system parameters

“…Similar assumptions were made in some other studies on rail rollover. 7,8 To theoretically understand and simplify the track structure, mechanistic models are often proposed based on finite element simulation or field observation. A mechanistic model describes a system based on the fundamental physical laws that it obeys and looks into the functions of the system components.…”

Quantification of longitudinal fastener stiffness and the effect on fastening system loading demand

“…that have caused derailments. [4][5][6][7][8][9] Between 1999 and 2018 there were 250 Federal Railroad Administration (FRA) reportable derailments on mainlines and sidings in the United States caused by "defective or missing spikes or rail fasteners". 10 This iterative approach has led to the installation of fasteners in track where demands exceed capacity, inefficient designs, and an insufficient understanding of the underlying mechanisms that govern the track system's response to changing conditions (e.g., input loads, component wear, support conditions) that has manifested itself in maintenance and safety problems as evident from the review of FRA track-caused derailment data.…”