Influence of curvature radius on impact effects of a box-girder curved bridge under moving vehicle loads

Aiming at a complex coupled vehicle-bridge problem, a triple-beam model was applied to model bridge structure and a simple separation iteration solution method was presented based on ANSYS program. The detailed derivation process and computational procedures of the problem were also presented and validated by the field dynamic test of a preselected dual-box girder curved bridge. The inverse fast Fourier transformation was applied to generate road irregularity and its velocity term of grade B according to power spectral density of road roughness. The curvature radius and vehicle speed effects were analyzed based on the dynamic amplification factor (DAF) of a curved-bridge considering the traveling eccentricity of vehicles. The results indicated that the DAF of the curved bridge is larger than that of a straight bridge, and DAFs of internal forces and displacement at different positions are different significantly; the internal forces and displacements have different sensitivities to curvature radius, and their DAFs vary greatly while the curvature radius is smaller than a certain characteristic value.