基于双层平面索变形的车辐式张拉结构找形方法  

The form finding method for spoke tension structure based on double planar layers of cables

作　　者：尚仁杰[1] 吴转琴[1] 刘景亮[1] 

机构地区：[1]中冶建筑研究总院有限公司,北京100088

出　　处：《应用力学学报》2013年第5期720-725,803,共6页Chinese Journal of Applied Mechanics

摘　　要：建立了由上层索、下层索、飞柱组成的双层平面索结构,根据节点平衡推导了各索段拉力的计算公式;基于索拉力产生的平衡荷载与索拉力水平分量及索竖向变形之间的关系,推导了平面索在竖向荷载作用下变形计算的有限元列式;通过对平面索结构边界节点施加竖向位移,将上下索边节点移动到建筑要求的位置;当飞柱高度不同时,可通过飞柱的伸长或缩短达到设计要求的飞柱高度,最终实现车辐式张拉结构找形。本文还给出了找形后结构分析和索张拉控制所需的初应变计算公式以及考虑边界梁和柱子在索力下产生弹性变形的处理方法。通过对车辐式张拉结构工程实例进行找形计算,介绍了有限元法的计算过程;对找形后车辐式张拉结构进行了受力分析,将找形时结构荷载施加在找形后的结构上,结构最大竖向位移仅为0.72mm,验证了该找形方法的正确性。The spoke tension structure can be formed through the deformation of two parallel layers of cables.The structure of double planar layers of cables is built up of upper cables,lower cables and flying columns horizontally.The FEM equation of the structure is deduced in the paper based on the relationship of balanced loads and the form of cables and the horizontal tensions of the cables.The boundary nodes are imposed to dispancement conditions to satisfy the architecture requirements.The heights of the flying columns are achieved through the elongation or shrinkage when they are different.The FEM process to find the form of the spoke tension structure is introduced by an engineering project.The analysis of the spoke tension structure under the applied load after the form-finding is carried out and the correctness of the method is confirmed.The method in the paper has the definite physical meaning,and is easy to carry out with high accuracy.

关 键 词：车辐式张拉结构 平面索 索桁架 平衡荷载法 找形 有限元法 

分 类 号：TU394[建筑科学—结构工程] O342[理学—固体力学]