悬索桥成桥状态计算方法

假设悬索桥主缆自重沿弧长均匀分布，加劲梁、桥面等其余恒载沿水平均匀分布，考虑主缆弹性伸长对其自重集度的影响，导出了以参数u（shu=dy／dx）表示的主缆线形方程。由边界条件，建立了求解主缆水平张力和端点未知参数的非线性方程组，采用拟牛顿法求解。然后通过改变参数u来确定主缆线形坐标。最后由积分法导出了主缆索有应力和无应力长的计算公式。算例表明该方法收敛速度较快，计算精度较高，可用于悬索桥设计与施工控制计算。

Analytical Methods of Suspension Bridge Geometry under Dead Loads

On the assumption that self-weights of main cables for suspension bridge are uniform distributed along arc length and the rest dead loads such as stiffened girder and bridge deck are uniform distributed along horizon,the analytical equations of main cable shape are deduced and are expressed with a parameter u(shu=dy/dx) on the consideration of the influence on self-weight intensity of the elastic elongation of main cable.Based on the boundary conditions,the problem is reduced to a set of nonlinear(equations.) The unknown parameter of end and horizontal component of tension of main cable are solved by quasi-Newton methods.By the change of parameter u,the coordinate of main cable shape can be determined.Then the calculation formulas of stressed and unstressed cable length are required by the cable element length's integral method.The results from an engineering case show that the methods are quick in convergence with high precision,are applicable for the design and construction calculation of suspension bridge.1 tab,3 figs,6 refs.