Refined dynamic analysis of three slab tracks on bridge structures under various high-speed train loads

Abstract

The dynamic performance of three slab ballastless tracks in the China Railway Track System (CRTS), which is supported by a simply supported box girder under various train loads, were comprehensively investigated with refined rigid-flexible coupled models. A refined rigid-flexible coupled model of vehicle-multi layer track-bridge system was developed to investigate the dynamic performance of three various CRTS slab tracks (i.e., CRTS I, II, III) under various conditions of train models, speeds and loads, respectively. The numerical analysis was conducted by using the combination of ANSYS and Universal Mechanism. It shows that the developed refined model has the capability of simulating the vehicle-slab track-bridge interaction with consideration multi-layer track structures, and the model predictions agree reasonably well with the experimentally measured wheel load reduction rate, lateral displacement and lateral acceleration of the bridge under different train speeds. The parameters of derailment system, vertical and lateral acceleration, the wheel-rail contact force, and Sperling index gradually become larger with the increase of the train speed, especially when the speed increases to 350 km/h. In addition, there is a significant increase in vertical wheel-rail contact force while a decrease in Sperling index when the train with full load capacity. Furthermore, the CRTS III slab track has demonstrated a better dynamic performance of track and bridge structures in comparison to CRTS I and CRTS II slab ballastless tracks.