Cumulative effects of cracking in monoblock multipurpose precast concrete sleepers on railway tracks

Abstract

This work addresses the phenomenon of cracking in multipurpose precast monoblock concrete sleepers by examining the entire process from fabrication to final installation on railway tracks. This includes stages such as manufacturing, stockpiling, track installation for rail neutralization, and eventually fastening the rails to the sleepers. A nonlinear numerical model, which is experimentally validated, is used to analyze this effect. Also, thermal and mechanical actions are considered at each stage of the process. Accordingly, different types of polymeric dowels and concrete aggregates—siliceous and carbonate—are evaluated to assess their impact on cracking. The results indicate that the thermal expansion capacity and elastic stiffness of the dowels, as well as the outdoor temperatures during fabrication, stockpiling, and installation, play critical roles in the cracking process. Sleepers made with carbonate aggregate, stiff-expansive dowels, fabricated in cold environments, and installed in hot conditions are particularly prone to severe cracking. Consequently, these conditions should be avoided to minimize cracking in multipurpose sleepers.