The impact effects of the vehicle dynamic loads should be considered in designing bridge structures. To calculate the vibration response of long-span curved bending beam bridge caused by vehicle, form function matrix was created by introducing high order displacement interpolation function in the nodes. Based on virtual work principle and dynamic finite element theory, spatial element stiffness matrix and density matrix of curved box girder bridge with 9 freedom degrees in each node were deduced, the restricted torsion and shear lag effect were considered in deducing stiffness matrix, the influence that mass center didn’t coincides with torsion center was also considered in deducing density matrix. The vibration equations of vehicle-bridge coupling were established by introducing vehicle mode with 7 freedom degrees. Newmark-βmethod was used on MATLAB to solve vibration response of system under vehicle dynamic loads, and influences of vehicle speed, vehicle weight and primary beam stiffness on impact coefficient were analyzed. The results show that when displacement impact coefficient was used to replace moment and shear impact coefficient for section internal force design, moment design value would maximally increase by 2.89%, shear force design value would maximally decrease by 34.9%; vehicle weight had a little influence on impact coefficient; displacement and moment impact coefficients decreased with the increasing of primary beam stiffness, while shear force impact coefficient increased with the increasing of primary beam stiffness; the theoretical calculation values agreed well with the finite element results of ANSYS.
