强震下三片叠合式旋转开合球面网壳屋盖的失效模式及防倒塌策略  

Failure modes of spherical reticulated shell in triad-overlapped revolvingly retractable roofs under strong earthquakes and anti-collapse strategy

作　　者：周健 邓华[1] ZHOU Jian;DENG Hua(Space Structures Research Center,Zhejiang University,Hangzhou 310058)

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》2021年第2期11-18,55,共9页Spatial Structures

摘　　要：以日本福冈穹顶为背景,分析了200m跨度三片叠合式旋转开合球面网壳屋盖的动力特性以及7、8度中震及大震下的杆件塑性发展特点及失效模式.针对8度大震下结构可能出现倒塌的情况,考察了基于控制模态力法的杆件加强策略的有效性.结果表明:8度小震对杆件截面验算不起控制作用,且仅通过小震验算的球面网壳在8度大震作用下可能发生倒塌;靠近主壳与底扩区转折处的腹杆或支座区上弦杆容易形成屈曲带并诱发网壳倒塌;屈曲带各杆件在非抗震设计及抗震设计下的最不利内力存在较大差异是形成薄弱区的主要原因;采用针对性加强薄弱区杆件的控制模态力法对保证结构在地震烈度为8度时的"大震不倒"是有效的.当控制模态力的组合系数为8.0时,网壳用钢量的增幅约11.2%.The dynamic properties,the plastic development of members and the failure modes under 7-degree or 8-degree fortification intensity and rarely-occurred earthquakes were investigated for a 200-meter-span spherical reticulated shell which is used in the triad-overlapped revolvingly retractable roofs typical of Fukuoka Dome in Japan.A member reinforcement strategy based on the dominant modal force method was employed to prevent the possible collapse of the structure under 8-degree rarely-occurred earthquakes,and its validity was analyzed.Results show that 8-degree frequently-occurred earthquakes play a negligible role in the cross-section check of members,but the spherical reticulated shell whose members even pass the cross-section check for the frequently-occurred earthquakes may collapse under 8-degree rarely-occurred earthquakes.Buckling zones easily appeared in the web members near the contour turning point between the main shell and the bottom expansion areas as well as the upper chord members in the bottom support region,inducing the collapse of the reticulated shell.The major difference between the most unfavorable internal forces of the members in the buckling zones under the non-seismic design and the seismic design was the main reason for the formation of weak areas.The members in the weak areas were effectively reinforced by the dominant modal force method to prevent the structure from collapsing under 8-degree rarely-occurred earthquakes.When the combination coefficient of the dominant modal forces reaches 8.0,the steel consumption of the reticulated shell increased by about 11.2%.

关 键 词：开合屋盖 球面网壳 旋转开合 抗震性能 失效模式 防倒塌策略 

分 类 号：TU393.3[建筑科学—结构工程]