Design of a Full-Scale Test Rig to Simulate Moving Train Loads on Railway Track for Fatigue Behavior Investigation

Understanding the dynamic response of railway track and its long-term behavior under moving train loads is necessary for improving track performance. In this study, a full-scale test rig using fixed hydraulic jacks on a test track is designed to investigate innovative ballast and sleeper solutions. Previous laboratory tests applied dynamic loads sequentially to a few adjacent sleepers, using identical load amplitudes corresponding to the target sleeper reaction forces. To preserve the integrity of the track and simulate more realistic conditions, the loads in the present experiment are applied directly to the rail. Each load can be distributed along the rail and thus generate reaction forces on several sleepers within a certain range. An inverse beam-support model is therefore developed to determine the jack loads required to generate the targeted sleeper reactions induced by passing trains. Preliminary numerical results show that the calculated jack loads reproduce the reactions with acceptable accuracy. The loading frame is designed to be easy to assemble and movable along the test track. This proposed test rig enables full-scale dynamic loading while maintaining continuity and requiring only minimal modifications to the test track. It also provides the possibility to monitor the evolution of rail level and alignment, exhibiting advantages over previous approaches.