A methodology for vehicle-induced vibration of half-through tie-arch bridge

A three-dimensional finite-element model for the coupled interaction between a vehicle and a long-span tie-arch bridge was developed using the equation coupling method, incorporating both geometrical non-linearity and contact non-linearity. A comprehensive analysis on the impact coefficients of suspenders was conducted, considering various factors such as vehicle speed, bridge surface roughness, driving mode (single lane or double lanes) and vehicle type (two-axle and three-axle vehicles). The results showed that the impact coefficient of suspenders is higher at low vehicle speeds. The driving mode and vehicle type had a significant influence on the impact coefficients of suspenders. It was also found that, as the bridge surface roughness deteriorates, the suspenders experience larger impact forces, affecting the structural safety and durability of the bridge, as well as impairing driving safety and comfort. The results also revealed that the dynamic impact coefficients specified in design codes are not applicable to tie-arch bridges. Vehicle–bridge coupling model should therefore be used to compute dynamic impact coefficients accurately.