（东南大学土木工程学院，南京 210096）

［摘要］由于横索悬垂、复杂边界和不对称张拉等因素影响，大尺度单层平面索网玻璃幕墙中出现玻璃安装困难和索力耦联等问题。提出了单层平面索网结构的找形问题，并分析了该问题的独有特点和解决的必要性。针对此类找形问题，文中对非线性有限元逆迭代法进行推广，提供了方便实用的解决方法。为了提高迭代的收敛速度，引进了找形差值修正比例因子矩阵，并给出了该矩阵元素的具体计算公式。算例证明，该方法精确实用，表明单层索网玻璃幕墙支承体系的找形分析非常必要，而且经找形后的索网索力分布更均匀，减少了两个方向索力的耦联，提高了索网结构的安全性和经济性。

［关键词］单层索网；找形分析；非线性有限元逆迭代法；玻璃幕墙；找形差值；悬垂度；预张力

中图分类号：TU323.8文献标识码：A文章编号：1002-848X(2011)03-0014-05

Form-finding of singlelayer plane cable net

Weng Zhenjiang, Shan Jian, Yin Lingfeng, Huang Wei

(College of Civil Engineering, Southeast University, Nanjing 210096, China)

Abstract:Many problems, such as difficult glass installation, coupled cable tension, are appeared in large scale single-layer cable net glass curtain wall due to the affection of  suspension deflection of horizontal cables, complicated boundary, asymmetric tensioning etc. Form-finding for single-layer plane cable net was put forword, and the characteristics and the necessity of solving the problem were analyzed. A convenient and applicable solving method was provided by generalizing and improving the nonlinear finite element inverse iteration method. A modified ratio factor matrix was introduced for increasing the convergence rate of iteration.The specific formulae were given for calculating the matrix elements. Two given examples indicate that the proposed method is accurate and practical. Conclusions are drawn that formfinding analysis for support system of single-layer cable net glass curtain wall is necessary, and it can make the cable tension no-coupled and distribution more uniformly, ultimately enhances the safety and economy of the cable structure.

Keywords:single-layer cable net; form-finding analysis; nonlinear finite element inverse iteration method; glass curtain wall; formfinding difference; suspension deflection; pretension force

作者简介：翁振江，博士研究生，Email:zhenjiang001@163.com。

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