预应力斜拉桥受到多种荷载及温度作用从而容易出现裂缝。传统的有限元方法不能精准刻画裂缝的产生与扩展，基于连续-非连续单元法，结合多物理场耦合对预应力桥面板展开数值模拟，对当前裂缝成因、长期演化进行了分析。结果表明：桥面板自身重力、拉索索力及桥梁弯直程度不是构成桥梁出现裂缝的主要原因，同时钢筋预应力在一定程度上有阻碍裂缝开展的作用；温度长期循环作用对桥面板初始裂缝起主导作用，后期车辆动荷载反复加载使初始裂缝进一步扩展。
Prestressed cable-stayed bridges are prone to crack due to various loads and temperatures. The traditional finite element method can not accurately describe the generation and expansion of cracks. In this paper, numerical simulation of a prestressed bridge panel is carried out to analyze the origin and long-term evolution of cracks based on the continuousdiscontinuous element method and multi physical field coupling. The results show that the gravity of the bridge panel itself, the cable force and the degree of bending and straightness of the bridge are not the main reasons for cracks of the bridge and that the prestress of the reinforcement hinders the cracks to a certain extent. The long-term cyclic effect of temperature plays a leading role in the initial crack of the bridge panels, and repeated loading of vehicle dynamic load in the later period makes the initial cracks further expand. The research results of this paper can provide a certain theoretical reference for analyzing causes of
bridge cracks.
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