曲线斜拉桥主梁扭矩分布优化及试验验证

Optimization and Test Verification of Torque Distribution of Main Girders of Curved Cable-Stayed Bridges

为获得工程可应用的曲线斜拉桥主梁扭矩分布优化的简易方法,根据曲线斜拉桥的力学特点,由初等静力学关系建立其主梁扭矩分布计算的简化模型,在此基础上提出采用设置曲线内、外侧斜拉索不对称初张力和调整支座位置的联合优化方法,实现曲线斜拉桥主梁扭矩分布的优化。给出联合优化方法的实现流程,以某座混凝土Π形主梁曲线斜拉桥为工程背景,分别采用有限元数值分析及模型试验验证该方法的正确性和可行性。结果表明:该方法能有效改善曲线斜拉桥主梁扭矩分布及曲线梁段不平衡的支座反力分布,将其应用于实际工程正确、可行。该方法分析过程简单、易于操作、经济实用、效率较高。

To acquire a simple approach that is applicable to the engineering to the optimization of the torque distribution of the main girders of curved cable-stayed bridges, the simplified model for the calculation of the torque distribution was established by the elementary statics relationship in accordance with the mechanical characteristics of the bridges. Based on the established model, the combined optimization method of setting the asymmetric initial tension of the stay cables on the inner and outer sides of the curves and of adjusting the bearing positions was proposed in order to achieve the optimization of the torque distribution. The process flow of the optimization method was given, a curved cable-stayed bridge with the concrete II-shape main girder was cited as an ex-ample and the correctness and feasibility of the method was verified, respectively by the finite ele-ment numerical analysis and the model tests. The results yield that with the method, the torque distribution of the main girders of the curved cable-stayed bridges and the unbalanced reaction force distribution of the bearings in the sections of the curved main girders can be effectively improved. The application of the method to the practical engineering is correct and feasible. The analysis process of the method is also simple, easily operational, economic and highly efficient.