薄壁断面曲线高架桥的空间结构分析

THREE-DIMENSIONAL STRUCTURAL ANALYSIS OF CURVED ELEVATED BRIDGE WITH THIN-WALLED OPEN AND CLOSED SECTIONS

本文在根据薄壁曲线梁翘曲扭转理论推导出的薄壁断面曲线粱单元空间刚度矩阵和各类荷载作用下空间等效节点力计算方法的基础上,提出了用刚度法进行曲线高架桥的空间结构分析方法,它可以用来计算正交抗扭线性支承、斜交抗扭线性支承、独柱式点支承以及支座预偏心等不同支座条件下的曲线高架桥的内力和变形,并可考虑桥墩对梁部结构的影响。文末通过对二跨斜支承曲线高架桥的计算实例,探讨了在均布荷载(自重)作用下支座偏角及翘曲对结构变形和内力的影响。

In this paper a method of three-dimensional structural analysis of curved elevated bridge with thin-walled section has been developed, which is based on the stiffness matrix formulation of a spatially curved, thin-walled beam element and a computational method for the equivalent space nodal forces, derived by the warping torion theory of curved thin-walled girder. The approach proposed herein can be used to calculate the internal forces and displacements of curved elevated bridges under different conditions, such as linear bearing of torsional restraint disposed either perpendicularly or obliquely to the ourved longitudinal axis, intermediate support with a single column of torsional unrestraint, presence of an eccentricity at a support, etc.. Numerical examples are given for a skew, curved elevated bridge. The effects of support inclination and warping stiffness on the magnitudes of the internal forces and displacements both for open and for closed sections of this bridge have been studied.