Investigation of Tie Plate Icing/Ice Jacking

Abstract

Tie plate icing (or ice jacking) is a cold weather railway phenomenon understood as a build up of ice and/or snow between the tie plate and the base of the rail, which causes a safety risk to railways in cold climates, and has caused derailments in the past. In addition to an investigation into root causes, this report sought to understand operational safety impacts, identify potential monitoring methods, and propose remedial actions to the phenomenon. Three field inspections occurring between January and April of 2022 were performed, measuring weather conditions and site and track characteristics to determine lateral track gage strength and widening. Conditions of concern were identified as areas where rail is not tightly seated to the tie plate, and inclement weather causes snow or ice to accumulate. Tie degradation, fastener deterioration, ballast fouling, high rail neutral temperature, hanging ties, and rail pumping were all risk-contributing factors. “Snow jacking” vs. “ice jacking” are also identified as separate weather conditions with jacking mechanics distinguishable from one another. Some measures identified to mitigate these conditions include improved drainage design, manual ice removal, geometry tightening, and degraded tie and fastener replacement. To better understand the mechanics of these conditions, a preliminary finite element model was developed including the variables of fastening conditions, jacking severity, and rail neutral temperature and curvature. Future work is suggested to validate this model through laboratory testing, along with a survey of railroad companies’ best practices for inspecting, identifying, and remediating the issue beyond those identified in this report.