索撑单层球面网壳多点地震输入下的失效特征研究  

Dynamic failure of a cable-stiffened single layer two-way grid dome under seismic multi-support excitations

作　　者：张中昊 支旭东[2] 范峰[2] 李玉刚 ZHANG Zhonghao;ZHI Xudong;FAN Feng;LI Yugang(College of Water Conservancy and Civil Engineering,Northeast Agricultural University,Harbin 150030,China;School of Civil Engineering,Harbin Institute of Technology,Harbin 150090,China;School of Mechanics,Civil Engineering and Architecture,Northwestern Polytechnical University,Xi’an 710072,China)

机构地区：[1]东北农业大学水利与土木工程学院,哈尔滨150030 [2]哈尔滨工业大学土木工程学院,哈尔滨150090 [3]西北工业大学力学与土木建筑学院,西安710072

出　　处：《振动与冲击》2021年第22期60-65,74,共7页Journal of Vibration and Shock

基　　金：黑龙江省自然科学基金(E2018007);国家自然科学基金(51109037);黑龙江省博士后科研启动基金(LBH-Q17025);东北农业大学“学术骨干”项目(54936512)。

摘　　要：在双向网格型单层球面网壳的面内外布置拉索可有效地增强结构的刚度从而提高结构的承载能力,提出一种新型索撑网壳结构。该研究针对60 m跨度索撑单层球面网壳,采用位移时程分析方法,研究结构在一致输入和考虑地震动空间变化性的多点输入下的地震响应及其失效特征。通过关键节点的荷载位移响应、网壳杆件进入塑性比例、网壳损伤程度等指标考察不同地震荷载幅值下网壳结构的破坏形式,揭示索撑单层球面网壳结构的动力失效机理。结果表明:拉索的布置有效地增强了网壳结构的延性,在网壳发生较大位移时,结构不但没有发生破坏而且还能继续承受更大的地震荷载。一致输入下网壳杆件是从球面四个端点区域开始进入塑性,多点输入下网壳杆件塑性发展从支座外环开始逐渐向内环发展。对比一致输入,多点输入下网壳动力极限荷载大幅度降低,说明索撑网壳结构体系受地震动空间变化影响较大。网壳破坏形式为强度破坏,多点输入下结构的强度破坏特征更为显著。The arrangement of in-plane and out-of-plane cables in a two-way grid dome structure effectively enhances its stiffness and improves the bearing capacity.The seismic response and failure characteristics of a 60 m span cable-stiffened single-layer spherical reticular shell under uniform and multiple-support excitations with the consideration of the spatial variation of ground motion were analyzed.Based on the load displacement response at key nodes,the plastic proportion of the lattice shell member,and the damage degree of the latticed shell,the failure forms of the lattice shell structure under different seismic load excitation were investigated,and the dynamic failure mechanism of the single-layer spherical lattice shell structure was revealed.The results show that the in-plane and the out-of-plane cables effectively enhances the ductility of the lattice shell structure.Even if the reticulated shell has a large displacement,the structure still will not fail.The reticular shell members enter into plasticity from the four end areas under uniform excitation,while they will gradually enter into plasticity from the periphery support to the inner ring under multi-support excitation.Compared with the uniform excitation,the critical load of the two-way grid shell under multi-support excitation is greatly reduced.The failure forms of the reticular shell are all strength failure,and the strength failure characteristics under multi-support excitation are more obvious.

关 键 词：双向网格 拉索 一致输入 多点输入 动力失效 

分 类 号：S263[农业科学—农业水土工程]