超载对装配式梁桥横向联系疲劳损伤的影响

In order to study the fatigue damage degree of the transverse connection of prefabricated assembled beam bridges under overloading, we establish the fatigue evaluation process of the steel beam connection structure of the fabricated beam bridges based on the linear cumulative damage criterion. Taking a concrete girder bridge as an example, we investigate the influence of vehicle overload on the lateral contact fatigue damage of concrete girder bridge and analyze the factors such as overload ratio, overload rate, vehicle frequency, loading level and overload model. The results show that the fatigue life of transverse connection decreases significantly with the increase of overloading rate. Compared with the general running state of vehicles, the fatigue life of horizontal connection is more sensitive to the change of overloading rate. Compared with overloading rate and vehicle action frequency, the lateral contact fatigue damage is more sensitive to vehicle overload ratio and loading level. The influence of different overload models on the fatigue damage of transverse connection is obvious, among which the overload of four-axle vehicle and six-axle trailer has the most prominent influence on the fatigue damage of the steel plate connected with the transverse diaphragm beam. Strictly controlling the proportion of overloaded vehicles and the loading level of heavy vehicles can effectively delay the fatigue damage process of key components. The bridge load limit management should consider the difference of the impact of overloaded models on the fatigue life of bridge components.