The safety and durability of railway transportation networks can be enhanced by studying the conditions that lead to fatigue cracks in rails during service. Mechanical testing and computational simulation techniques can be used to investigate manufacturing processes such as roller straightening and the resulting residual stresses incurred during production of modern railroad rails. The goal of this research has been to determine fatigue crack growth and fatigue life of rails and establish safe inspection intervals for rails in field service.
Below: (left) A mechanical engineering graduate student prepares a steel rail for mechanical testing. (right) This finite element model of a rail was used to study the mechanical conditions that contribute to rail service life.
Collaborative research on railway fatigue has been led by Prof. Herman Nied in the Fracture and Solid Mechanics Lab in the Department of Mechanical Engineering & Mechanics at Lehigh. This work has been completed in partnership with investigators at Thornton-Tomasetti consulting and ArcelorMittal steel, and in collaboration with Lehigh Mechanical Engineering alum and emeritus Harvard professor John Hutchinson. Funding for this research was provided by the U.S. Department of Transportation and the Federal Railroad Administration.
Read more about this research in in the 2019 Proceedings of the ASME/IEEE Joint Rail Conference: Defect Growth Characterization in Modern Rail Steels.