斜拉网壳结构的非线性静力分析

斜拉网壳结构是一种新颖的杂交结构体系,是“刚性”和柔性基本结构结合的典型,可跨越更大的跨度。本文基于Taylor展开公式和变分原理,推导了具有二阶精度的空间杆单元新型几何非线性刚度矩阵。研究了斜拉索的非线性问题和塔柱简化计算问题。针对弹性和刚性支座,以及是否考虑塔柱共同工作等影响因素,借助孤长法,数值计算了斜拉柱面和斜拉穹顶网壳结构极限承载力问题;同时,分别与相应的网壳结构计算结果进行了比较,最后,得出了有应用价值的结论和建议。

Nonlinear Static Analysis for Cable-stayed Reticulated Shell Structures

The Cable-stayed Reticulated Shell Structure (CSRS) is a kind of so called hybrid structural system, composed of "stiff" and flexible structures. The CSRS can stride accross larger span than most of the trsditional spatial structures. This paper lays emphasis on the research of nonlinear static analysis and ultimate bearing capacity of the CSRS.According to the Taylor deploying formulation and variation principle, a novel TOtal Lagrangian formulation of a 3-D bar element for large displacement and infinitesimal rotation analysis is developed. The nonlinear analysis of a cable element is camed out. The simplified linear stiffness matrix of a tower column element which the cable elements link to is developed considering the column as a kind of a special element. By means of a nonlinear static analysis program compiled by the authors,some nonlinear numerical examples of CSRS for determining the ultimate bearing capacity are investigated respectively. In these examples, more attention is paid to such influencing factors as elasticor stiff supporting conditions as well as whether or not taking into account the tower colunms workingtogether with the reticulated shell structure(RSS). The numerical comparisons between CSRS and RSS under the same loading conditions are also made. Finally, some conclusions and suggestionsare presented in this paper.