Dynamic response properties of two-way subgrade in bridge-subgrade transition section under moving load

A 3D finite-element model was established by using finite element method to systematically study the dynamic response characteristics of subgrade in bridge-subgrade transition section of heavy haul railway under dynamic load.The response rules were summarized after analysis.It is pointed that the displacement curves of the points in horizontal direction of subgrade are assumed W shape under moving towards load.The displacement of the point at the center of loading area is largest,and the maximum displacement on the left of subgrade is larger than that on the right.More close to the loading center,the displacement change of the point is more dramatic.The result indicates that the load not only has impact on the displacements of the points on its action side,but also exacerbates the ones on the other side.Along the depth direction,the impact of load on subgrade displacement wears off.