01519016

Component

To support the increasingly rigorous performance demands due to growing heavy-haul freight operations and increased high-speed intercity passenger rail development worldwide, advancements in concrete crosstie fastening system designs are needed. Improvements to the components responsible for attenuating loads and protecting the concrete crosstie rail seat will enhance the safety and efficiency of the track infrastructure. Rail pad assemblies are designed to provide a protective layer between the rail base and crosstie and attenuate the dynamic loads imposed on the rail seat, reducing the stresses to acceptable levels. Understanding the mechanistic behavior of rail pad assemblies is critical to improving the performance and life cycle of the infrastructure and its components, which will ultimately reduce the occurrence of potential failure modes such as rail seat deterioration (RSD). Lateral, longitudinal, and shear forces exerted on the components of the fastening system can result in displacements and deformations of rail pad assemblies with respect to the rail seat. The high stresses and relative movement are expected to contribute to multiple failure mechanisms and result in an increased need for costly maintenance activities. Thus, the analysis of the mechanics of pad assemblies is of paramount importance for the improvement of railroad superstructure component design and performance. In this study, the shear behavior of this component will be investigated from a mechanistic perspective that combines laboratory and field experiments to explain how the surfaces interact, show how the materials deform, and quantify the amount of relative displacement between the fastening system components. The expected results will lay the groundwork for the development of a mechanistic design approach that enhances the performance, efficiency, and durability of current concrete crosstie fastening systems.

This paper was sponsored by TRB committee AR050 Railroad Track Structure System Design.

01503729

14-3915

English

13p

2014

Transportation Research Board 93rd Annual Meeting

Digital/other

Figures; Photos; References

Concrete ties; Fastenings; Laboratory tests; Load tests; Mechanical loads; Railroad ties; Tie pads

Design; Railroads; I22: Design of Pavements, Railways and Guideways

Transportation Research Board Annual Meeting 2014 Paper #14-3915

TRIS, TRB, ATRI

Jan 27 2014 3:21PM