自锚式悬索桥简化计算方法研究

Study on Simplified Calculation Method of Self-anchored Suspension Bridge

基于能量原理,提出计算自锚式悬索桥受力性能的简化计算方法,对双塔三跨自锚式悬索桥导出求解加劲梁内力、挠度和主缆水平分力的基本公式。该法将自锚式悬索桥的主缆和吊杆截开,用未知力来代替,分别取主缆和连续加劲梁为隔离体进行分析,通过迭代逐步逼近,使两者满足受力协调条件,对主缆同时考虑恒载和活载作用下的挠度,对加劲梁同时考虑轴力和弯矩的作用以及梁柱效应。算例结果表明,该简化计算方法的计算结果收敛速度快,与几何非线性有限元法的计算结果吻合良好。

On the energy principles, a simplified method for calculating the behavior of the self-anchored suspension bridge was proposed. The basic formulas for calculating the forces and deflection of the stiffening girder and the horizontal component forces of the main cable of the twin-tower three-span self-anchored suspension bridge were deduced. The main cable and hangers of the self-anchored suspension bridge were truncated and replaced by unknown forces. The main cable and continuous stiffening girder were taken as respective isolating bodies in analysis and they were made gradually matched in stressing conditions by the iteration method. The defections of the main cable both under the dead load and live load were considered. The actions of both the axial force and bending moment on the stiffening girder and the beam-column effect were considered. The results of the examples show that the results got from this method coincide with those got from the geometry-nonlinear FEM method and their convergence rates are fast.