大跨度斜拉桥大位移影响的非线性静力分析

Nonlinear Stactic Analysis about the Effect of the Large Displacement of the Long-span Cable-stayed Bridge

大跨度斜拉桥由于拉索的柔性、梁自身刚度较小以及梁柱相互影响而产生非线性问题,使有限元平衡方程中的小变形叠加原理不再适用,针对此问题,应用带动坐标混合法求解非线性问题,论述了其单元刚度矩阵的基本原理及其迭代过程.这一方法已在桥梁建设中得到广泛应用,且其计算精度符合工程要求.

Many nonlinear problems in the long-span cable-stayed bridges have happenned because of the flexibility for the stay cable, the little stiffness for the beam,and the effect between the beam and piers. These problems make the minimum displacement superposition principle in the finite element balance equation no longer suit. for these problems,the calculation principle of the nonlinear problem are discussed for the effect of the large displacement,the iterative process and the method to solve the element stiffness matrix by mixed optimization method. This method is applied widely in the field of bridge construction and its computational accuracy accord with the engineering need.