Based on the finite element method and the theory of interaction between beam and rail, for girder bridge and the simply supported girder bridge which are common rail continuous bridge as an example, this establishes on railway line - bridge - bridge pier integration calculation model and analyzes the influence of the type of load and load range on the bending force law.

A vehicle-track-subgrade coupling vibration system model was proposed to analysis the influence of cell plate length to slab track vertical dynamic response. The model was built with finite element method, rail was modeled as space beam element, both track plate and base plate were modeled as shell element, the vertical connections between rail, slab and subgrade were modeled as spring-damper element. The results show that with the cell plate length increases, the vertical vibration displacement of rail, track plate and base plate have decreasing tendency; the vertical vibration acceleration of rail has increasing tendency; the vertical vibration acceleration of track plate and base plate have decreasing tendency.