Investigation of the Impact of Abrasion as a Concrete Crosstie Rail Seat Deterioration (RSD) Mechanism

Abstract

To meet the demands of increasing freight axle loads and cumulative gross tonnages, and high-speed passenger rail development in North America, the performance and service life of concrete railway crossties must be improved. According to a railway industry survey conducted by the University of Illinois at Urbana-Champaign (UIUC), rail seat deterioration (RSD) was identified as one of the primary factors limiting concrete crosstie service life. While previous research at UIUC focused on the moisture-driven mechanisms of RSD, the purpose of this study is to define and characterize abrasion in order to understand the criticality of abrasion as a failure mechanism. Abrasion is widely considered to be a viable mechanism leading to RSD; nonetheless, a lack of understanding of the complex properties affecting abrasion has resulted in a highly iterative design process for concrete crossties and fastening systems. When combined with abrasive fines and water that penetrate into the rail seat and pad interface, the frictional forces and relative movement of the concrete crosstie and fastening system equate to a seemingly ideal situation for the occurrence of abrasive wear. This paper includes an investigation of the tribological properties at the interface of the rail seat and pad and preliminary results from an experimental evaluation of the parameters that are believed to affect the rate of abrasion. By identifying the parameters that contribute to RSD, UIUC’s research will seek to mitigate the effects of abrasion with an overall goal of improving the performance of concrete crossties.