Sensitivity Analysis of Impact Coefficient for Large Transport Vehicle Crossing Bridge

When the vehicle speed is very low, it is generally believed that the impact coefficient of vehicle load can be ignored. However, under the conditions of uneven bridge deck and heavy cargo transportation, the impact coefficient of the bridge when the vehicle is running at low speed cannot be ignored. In order to study the sensitivity of the impact coefficient of large transport vehicles crossing the bridge, this paper first establishes the bridge structure model and vehicle model, and uses the range analysis method to influence the impact coefficient of 12 influencing factors, such as the unevenness of the bridge deck, the stiffness of the bridge structure, and the vehicle mass. The research results show that the method of neglecting the impact coefficient of vehicle load in the existing safety assessment of large transport bridges often makes the bridge structure in a state of potential safety hazard. The impact coefficient is affected differently by different factors. For mid span deflection and bending moment, the primary and secondary order of impact factor is: concrete elastic modulus > bridge deck flatness grade > vehicle speed > structural Rayleigh damping constant. For shear force, the primary and secondary order of influencing factors of impact coefficient is: vehicle speed > concrete elastic modulus > bridge deck flatness grade > structural Rayleigh damping constant.