Enhancing the Performance of High-Speed Railway Slab-Ballast Transition Zones Using Geotextile Reinforcement: A Dynamic-Equivalent ۳D Finite Element Investigation

Transition zones between ballast and slab tracks are critical points in high-speed railways due to abrupt stiffness variations. This study investigates the optimization of speed-induced track responses in railway transition zones using geotextile reinforcement through a three-dimensional finite element dynamic-equivalent analysis. To address the inherent tensile weakness of the ballast layer, various geotextile lengths (۶, ۹, and ۱۲ m) were modeled under heavy loading at speeds of ۱۶۰ and ۵۰۰ km/h. The numerical model was validated against experimental data of geosynthetic-stabilized soil under cyclic loading, showing a deviation of less than ۱۰%. Results indicate that increasing train speed significantly intensifies rail deflection and impact coefficients. However, the inclusion of geotextile over cement-stabilized ballast enhances confinement and tensile strength, leading to a ۶۰% reduction in vertical rail deformation compared to the unreinforced state. Among the tested configurations, a ۱۲-meter geotextile length provided the optimal performance in reducing vertical rail displacement and smoothing the stiffness transition. These findings demonstrate that geotextile reinforcement is a highly effective and practical reinforcement strategy for enhancing the structural integrity and longevity of high-speed railway transition zones.

کلیدواژه ها:

High-speed railway ، Transition zone ، Geotextile reinforcement ، finite element analysis ، Nonlinear dynamic analysis