针对多跨连续曲线梁的车桥耦合振动问题,分别采用三梁式模型和12自由度的车辆模型对桥梁和车辆进行模拟,通过快速傅里叶逆变换采用三角级数方法模拟了桥面不平度及其速度项,考虑桥梁结构阻尼的影响,采用基于ANSYS的分离迭代算法研究了多个车辆荷载共同作用下连续曲线箱梁桥不同控制截面位置的内力和挠度响应的主要差异及其随车速的变化规律.研究表明:横向加载车道数对支点扭矩、跨中扭矩、支点弯矩和墩顶截面弯矩的最大动力放大系数有很大影响,而对主梁的竖向挠度和墩柱的轴力最大动力放大系数影响很小；纵向加载车辆数对桥梁的冲击效应有很大影响；桥梁的动力放大系数随车头间距增大显著提高而最大效应则大大减小.研究结果可为多跨连续曲线箱梁桥的设计提供参考.%The dynamic behavior of a multi-span continuous curved bridge under heavy trucks passing was investigated, the bridge was discretized with a triple-beam model and the trucks were simulated with a 12-DOF model. The inverse fast Fourier transformation was applied to simulate road irregularity and its velocity term of grade B according to the power spectral density of road roughness. The impact effects at various positions of the curved bridge under multi-vehicle action with different velocities were investigated considering the bridge structural damping using the separated iteration method based on ANSYS. The analysis results showed that the number of lateral loading lanes has a great effect on the fulcrum and the mid-span torques, the fulcrum bending moment and the bending moment maximum dynamic amplification factor of the top pier cross-section, while it has little effect on the maximum deflection dynamic amplification factor of the girder and the maximum axial force dynamic amplication factor of the pier; the number of longitudinal loading vehicles has significant influence on the bridge impact effects; the impact factors increase with increase in space headway but the corresponding maximum responses decrease. The presented results provided a reference for design of continuous curved box girder bridges.
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