Research on Fatigue Damage Evolution of the Base Plate Structure of China Railway Track System III Type Slab Ballastless Track under Heavy Haul Train Load

To meet the transportation requirements of heavy-haul trains, it is necessary to consider the use of prestressed reinforced concrete ballastless tracks. Therefore, the CRTSIII SBT (China Railway Track System III-type slab ballastless track) has been considered for its convenient construction and geometric adjustment. Considering the problems existing in the base plate of CRTSIII SBT in heavy-haul applications, an indoor test and simulation were conducted to explore the cracking phenomenon of the base plate concrete under fatigue load. The reliability of the simulation was verified through the experimental results. A fatigue crack development law of the base plate structure was established. Furthermore, the influence of the load position, the thickness of self-compacting concrete and axle loads on the fatigue damage of the base plate structure were investigated. For the CRTSIII SBT subjected to heavier axle loads, it is appropriate to thicken the self-compacting concrete layer and strengthen the concrete and steel reinforcement at the plate end to reduce fatigue damage and cracks. The research results can serve as a basis for the optimization of the CRTSIII SBT base plate structure in heavy-haul railway applications.