Improving railway joint service life through computational analysis of its geometry

Insulated rail joints (IRJ) are essential points of vulnerability in a railway network that, due to degradation, impose a significant restriction on the operating uptime of a railway system. The IRJ degradation is caused by the combination between an inherent reduction of structural rigidity and the immense forces applied to the rail. The reduction of lifespan of the insulated rail joint is such that there is a reduction of operating capacity to one-tenth of the continuous welded rail system. As such the design for current insulated rail joints shows inadequacy in their design for modern railway operations. To improve the lifespan of the IRJ, the external reinforcement of varying geometry of IRJs has been considered. Using Finite Element Analysis (FEA) static, non-Hertzian analysis to investigate vertical forces on von-Mise stress, strains, bending rigidity, and fatigue life cycles, a comparison of the original vs modified IRJs models was made. There was no key outlying geometry found in comparison to the other geometries, with only small improvements between each geometry. With that said, the Squared Hollow Section (SHS) geometry gives the best life span. The SHS has a theoretical service life considerably higher than that of the 12 to 18 months achieved by the original IRJ shape. Therefore, the application of a reinforcing rail theoretically provides significant improvement to IRJs.