Long-Term Performance of Ballastless High-Speed Railway Track Under the Conditions of Ground Water Level Variations

High-speed railways will be exposed to high water level caused by extreme water conditions, such as floods and heavy rainfall, which may influence the soil structure of roadbed, leading to excess accumulative deformation under dynamic train loads. The development of uneven deformation of railway track will then exacerbate the wheel–track interaction, which in turn accelerates the degradation of high-speed railway roadbed and jeopardizes the safety of train running. To verify the long-term performance of high-speed railway road under various water level conditions, a full-scale physical model of a ballastless railway and a sequential loading system were developed which can simulate train moving load at speeds up to 360 km/h. Water level in the physical model can be raised and lowered with a water level control system. Train moving loading tests were carried out at three typical water levels: at the subsoil bottom, at the subsoil surface and at the subgrade surface. In each water level condition, three different train velocities: 108, 216 and 360 km/h were simulated for a certain number of cyclic loads. Some results of dynamic pore water pressure are presented in this paper.