空间缆索自锚式悬索桥成桥状态的确定方法

结合悬链线理论和几何非线性有限元方法,对空间缆索自锚式悬索桥成桥状态的确定方法进行了研究。提出了空间主缆和吊索的线形及内力的迭代计算方法,在此基础上建立成桥状态的几何非线性有限元模型,进行非线性迭代计算并不断修改单元无应力原长及刚度矩阵,直至节点位移满足精度要求,即确定了全桥结构的成桥状态。利用该方法能得到满足设计要求的自锚式悬索桥成桥状态,并得到了主缆、吊索、加劲梁的线形、杆件内力等重要信息。算例验证表明了该计算方法是可行的,能够满足工程计算精度要求,可用于空间缆索自锚式悬索桥成桥状态的确定。

A Method for Determining Dead-load State of Spatial-cable Self-anchored Suspension Bridge

The catenary theory and geometrical nonlinear finite element method were adopted in determining the dead-load state of self-anchored suspension bridge with spatial cables.The iteration method of geometric shapes and internal forces of spatial cables and hangers was presented,and the geometric nonlinear finite element model was set up.The unstrained lengths and stiffness matrix were revised continually until the nodes' displacements met the precision requirement in the processing of nonlinear iteration calculation.Then the dead-load state of the whole bridge was determined.With this method,the dead-load state that meets the design requirement of self-anchored suspension bridge and the geometric shapes and internal forces of cables,hangers,and stiffening beams can be obtained.A presented example proves that the method is valid and feasible for engineering requirement and determining the dead-load state of spatial self-anchored suspension bridges.