地震爆炸联合作用下桥梁响应与损伤的数值模拟

To obtain the dynamic response and damage law of bridges subjected to the combined action of earthquake and blast, a finite element (FE) model of one 30 m-span simply supported prestressed reinforced concrete girder bridge under the combined action of earthquake and blast was established using the software ANSYS/LS-DYNA as an analytical platform. A new simulation method that considers the combined action of seismic and explosive loads was utilized. Seismic wave EL Centro and a 250 kg TNT explosive were selected as applied loads acting on the structure. The damage condition and dynamic response of various bridge structural members were analyzed, and the damage law and failure type of structures under the combined action were summarized. The results show that the longitudinal displacement of the main girder increases and beam falling may occur under the combined action. The use of displacement limitation devices is suggested. When piers are subjected to the combined action, the damage area and the depth of piers will increase, and a fatal injury of the base being cut off may occur, causing failure of the carrying capacity. The occurrence time of the most severe pier damage and the damage severity vary under different loading directions.