Impact effect study on long-span irregular concrete filled steel tube arch bridge under moving vehicles

In order to research the impact effect characteristic of a long-span irregular CFST arch bridge, the dynamic response analysis on the interaction of vehicle and bridge was carried out by the self-compiling computing program for the Yitong River bridge under construction in Changchun city. The influence of road surface roughness, vehicle speed and damping on impact effect of bridge was analyzed by theory. Results show that the effect of road surface roughness on vibration response of the irregular arc bridge is significant, keeping good roughness level will decrease impact factors. The influence of vehicle speed on impact effect is related with the primary modes of response, and hence increasing vehicle speed may not increase impact factors. Damping ratio of the structure does not affect impact factors significantly when it is changed in a given scope by specification, and damping ratio of 5% can be used in the design for security. Moreover, reference values of impact factors of the bridge are given in the study.