框支框架结构抗连续倒塌性能分析  

Analysis of Progressive Collapse Resistance ofFrame-supported Frame Structures

作　　者：黄远[1] 陈庆 HUANG Yuan;CHEN Qing(Hu′nan Provincial Key Laboratory on Damage Diagnosis for Engineering Structures,Hu′nan University,Changsha,China,410082;College of Civil Engineering,Hu′nan University,Changsha,China,410082)

机构地区：[1]湖南大学工程结构损伤诊断湖南省重点实验室,湖南长沙410082 [2]湖南大学土木工程学院,湖南长沙410082

出　　处：《沈阳建筑大学学报（自然科学版）》2023年第5期800-809,共10页Journal of Shenyang Jianzhu University：Natural Science

基　　金：国家自然科学基金项目(51890901)。

摘　　要：目的研究框支框架结构的抗连续倒塌性能,为该类结构抗连续倒塌设计和研究提供参考。方法通过二次开发在ABAQUS中引入微平面模型,在对剪切试验以及框架抗连续倒塌试验合理验证的基础上,对框支框架结构进行受力分析,探究梁跨高比、结构侧向约束、梁上集中荷载位置和大小对结构倒塌性能的影响。结果转换梁的跨高比从5增至7,结构压拱承载力下降了32.7%,剪切破坏时的位移增加了127%;结构无侧向约束时,易形成强梁弱柱结构,导致柱发生破坏;当梁上集中荷载从0.4F1增至1.3F1、与失效柱的距离从l_(n)/3增至2l_(n)/3,剪切破坏位移分别减小了74%和70%。结论在倒塌过程中,转换梁的抗剪承载力不断下降从而发生剪切破坏,迫使结构从压拱机制突变为悬链线机制,但悬链线承载力不足以抵抗竖向荷载,负弯矩区纵筋发生断裂致使结构失效。In order to study the progressive collapse resistance of the frame-supported frame structure,the microplane model was introduced into ABAQUS by secondary development.The accuracy and rationality of the analysis model were proved through simulating shear and progressive collapse specimens.On this basis,the progressive collapse performance of the frame-supported frame structure was carried out,and the effects of beam span to height ratios,structural lateral constraints,locations and magnitudes of concentrated load on beam on structural collapse performance were investigated.Results showed that the shear strength of the transfer beam decreased continuously after the peak capacity of compressive arch action,resulting in shear failure,which made the structure suddenly change from compressive arch mechanism to catenary mechanism.The tensile force provided by the longitudinal rebars at the end of the beam in the catenary mechanism could not resist the external load,resulting in the fracture of the longitudinal rebars in the negative moment zone of the transfer beam and structural failure.The span-to-height ratio of the transfer beam increased from 5 to 7,the compressive arch capacity decreased by 32.7%and the displacement of shear failure increased by 127%;when the structure had no lateral restraint,it was easy to form a strong beam and weak column structure,resulting in column failure;the concentrated load on the beam increased from 0.4 F 1 to 1.3 F 1,or its distance from the failed column increased from l_(n)/3 to 2 l_(n)/3,the displacement of shear failure decreased by 74%and 70%respectively.

关 键 词：框支框架结构 抗连续倒塌 剪切破坏 微平面模型 数值分析 

分 类 号：TU375[建筑科学—结构工程]