网格结构中的杆件更换问题  

Some problems on bar replacement in reticulated structures

作　　者：王琼[1] 黄莉[1] 邓华[1] 

机构地区：[1]浙江大学空间结构研究中心,浙江杭州310058

出　　处：《空间结构》2013年第3期27-32,共6页Spatial Structures

摘　　要：在网格结构的杆件更换过程中,需要施加支顶力来保持新旧结构受力状态的一致性,所施加支顶力的大小可以通过杆系有限元法求解.如果需要更换的杆件较多,支顶力的计算过程比较繁琐,需要多次更改有限元模型.本文对于杆件更换时支顶力的求解提出了一种改进的方法,该方法不需要对模型的总体刚度矩阵作修改,有效减少了计算量.以杆件更换过程中产生的结构应变能误差最小为目标,可以找出多根杆件更换时最优的杆件更换顺序.按照改进后的方法求解,可以准确地求出最优杆件更换顺序,并且大大减少有限元的求解次数.During the bar replacement in space reticulated structures, jacket force should be exerted in order to make the condition of the new structure be consistent to the old one. And the jacket force can be obtained by the bar-based finite element method （FEM） analysis. When there are lots of bars to be replaced, the FEM model has to be updated again and again and thus the analysis will be cumbersome. A new method was brought up to solve the problem. With this method, the global structural stiffness matrix remains unchanged, thus reducing the computational efforts greatly. An optimal algorithm based on the minimum tolerance of structural strain energy to determine the sequence of bars to he replaced is also brought accordingly. The sequence of bars to be replaced can be determined accurately and the corresponding FEM computational efforts are reduced with the new method.

关 键 词：网格结构 杆件更换 有限元法 总体刚度矩阵 应变能 

分 类 号：TU356[建筑科学—结构工程]