拉索_网壳结构的动力特性和非线性动力反应

将空间网壳结构与拉索有机结合便形成拉索-网壳结构体系。该体系不但具有美学特征，更可进一步增大跨度。基于泰勒数学展开公式和变分原理，推导了具有二阶精度的空间杆单元几何非线性刚度矩阵；研究了拉索单元非线性问题，得出了其切线刚度矩阵；给出了结构非线性力学响应计算策略等。通过数值计算，分析了结构动力特性和非线性地震动力响应问题。计算结果显示，拉索-网壳结构的自振频率皆明显高于对应的网壳结构，且频谱较为密集，甚至不同序号的自振频率几乎相同，拉索-网壳结构的地震动力响应不但与拉索长度、截面尺寸、预拉力和布置方式有关，还与塔柱高度、截面尺寸等有关。

Dynamic Characteristics and Nonlinear Dynamic Responses of Cable_supported Grid Shell Structures

The cable_supported grid shell structure(CSGS) is composed of cables,towers and grid shell structures(GSS).The CSGS can cross larger span than most of the traditional forms of spatial structures.In the paper,it is focused on the study on its dynamic characteristics and nonlinear responses. In term of the Taylor deploying formulation and variation principle,a new formulation of a 3_D bar element for large displacement and infinitesimal rotation analysis is developed.The nonlinear analysis of a cable element is carried out.The computational strategies for the nonlinear dynamic responses of the structures are investigated.Some numerical examples of CSGS for studying the dynamic characteristics and nonlinear responses under seismic waves are investigated respectively.It is clear through the computations that the eigen frequencies of CSGS are higher than that of GSS and the frequency spectra of both CSGS and GSS are very densely spaced.It is also obvious that the vertical dynamic responses of both structures are remarkably greater than the horizontal ones.