基于显式弧长法的索杆张力结构成形过程数值模拟(英文)  

Numerical simulation of the erection process of cable-strut tensile structures using explicit arc-length method

作　　者：祖义祯[1,2] 邓华[1] 王玮[1] 

机构地区：[1]浙江大学空间结构研究中心,浙江杭州310058 [2]中国中元国际工程有限公司,北京100089

出　　处：《空间结构》2015年第1期90-96,共7页Spatial Structures

基　　金：Project supported by National Natural Science Foundation of China(50978226,50578139)

摘　　要：索杆张力结构的施工成形本质上是通过缩短主动张拉索长度来驱动的,因此其成形过程可通过一系列随张拉索长度变化引起的连续平衡构型来模拟.由于施工过程中结构几何的不稳定性,通常采用动力松弛法进行这种松弛索杆系统平衡形态的求解以避免建立系统的刚度矩阵.将张拉索长度作为控制变量,在动力松弛法基础上引入了一个位移约束方程.进而提出了一种显式弧长策略来实现索杆张力结构成形过程的自动跟踪求解.该方法的优点是在求解过程中通过限制控制变量的增量以使结构位移保持恒定增加,因而求得的成形过程较常规方法更平稳,甚至可跟踪到可能存在的奇异构型.对一个索穹顶算例进行了的成形分析,计算结果反映了本文方法的精确性和有效性.The erection of cable-strut tensile structures is substantially driven by shortening the length of actively-stretched cables, and the erection process is generally simulated by solving the continuous equilibrating structural configurations with the length change of those stretched cables. Due to the instability of structural geometry under construction, the Dynamic Relaxation （DR） method is usually employed to find the equilibrium configuration of this slack cable-bar assembly because no stiffness matrix is established in this method. Taking the lengths of stretched cables as control variables, a displacement constraint equation is introduced into the DR method. An explicit arc-length strategy is further suggested to automatically trace the erection configurations of cable-strut tensile structure. The merit of this method is as followed： the increment of control variables is constrained in order to keep a constant increment of structural displacements, thus the erection process is steadier than what is obtained by conventional method and can even present the possible singular configurations. Erection simulation of an illustrative cable dome is carried out, and the results show the accuracy and validity of the method put forward in this paper.

关 键 词：索杆张力结构 施工成形分析 动力松弛法 显式弧长法 运动路径 

分 类 号：TU323[建筑科学—结构工程] TU311.2