冷弯薄壁型钢货架梁柱节点子结构抗连续性倒塌性能研究  

Progressive Collapse Resistance of Cold-Formed Thin-Walled Steel Storage Rack Beam-to-Upright Connection Substructure

作　　者：任重 刘家巍[2] 戴柳丝 REN Chong;LIU Jiawei;DAI Liusi(Key Laboratory of Civil Engineering Structure and Mechanics of Inner Mongolia,Inner Mongolia University of Technology,Hohhot 010051,China;School of Mechanics and Engineering Science,Shanghai University,Shanghai 200444,China)

机构地区：[1]内蒙古工业大学内蒙古自治区土木工程结构与力学重点实验室,呼和浩特010051 [2]上海大学力学与工程科学学院,上海200444

出　　处：《建筑钢结构进展》2022年第9期36-44,66,共10页Progress in Steel Building Structures

基　　金：国家自然科学基金(51908347);内蒙古自治区土木工程结构与力学重点实验室资助项目(2021KF001)。

摘　　要：为研究冷弯薄壁型钢货架梁柱节点子结构的抗连续性倒塌性能,构建了考虑材料断裂的节点双半跨子结构精细化数值分析模型,综合考虑立柱、挂齿、螺栓等关键组件间的复杂接触关系。通过已有节点试验验证了模型准确性后,对6个具有不同立柱厚度、螺栓数目、横梁高度和梁跨高比的节点子结构进行精细化数值分析,揭示钢货架锁螺栓节点在连续性倒塌工况下的破坏模式和抗力机制,探究节点构造特征和梁跨高比等因素对节点内力效应和子结构抗力性能的影响机理。数值分析结果表明:锁螺栓节点在连续性倒塌工况下的破坏模式主要包括挂齿撕裂和立柱撕裂,以及挂齿撕裂和挂片端板剪断两类,且与立柱厚度紧密相关;梁柱节点子结构弯矩效应和轴力效应发展曲线存在一定规律,加载初期子结构弯曲机制抗力发展迅速,但所有节点子结构的竖向承载能力以悬链线机制的竖向抗力为主;节点构造对子结构抗连续性倒塌性能存在一定影响;梁跨高比越大,弯曲机制控制阶段越短,悬链线机制发挥得越快,但抗力越低。In order to study the progressive collapse resistance of a beam-to-upright connection substructure of cold-formed thin-walled steel storage rack,a refined numerical model of a double-half-span connection substructure is established by considering material fracture and contact relationship among the key components.After verifying the accuracy of the model with some existing test data,the refined numerical analysis is carried out on six connection substructures with different upright thicknesses,bolt numbers,beam heights and beam span-depth ratios to reveal the failure mode and resistance mechanism of steel rack bolted connections under progressive collapse.The influence mechanism of connection construction characteristics and beam span-depth ratio on connection internal force effect and resistance performance of substructures is studied.The numerical analysis results show that the failure mode of the bolted connections under progressive collapse mainly include two types,tabs and upright tearing,tabs tearing and connector shearing,which are closely related to the upright thickness.There are certain regularities in the development curves of moment effect and axial force effect of beamto-upright connection substructure.In the initial stage of loading,the bending resistance of substructure develops rapidly,but the vertical bearing capacity of all substructures is dominated by the vertical resistance of catenary mechanism.The connection characteristics have certain influence on the progressive collapse resistance of substructures.A larger ratio of span to height causes a shorter control stage of bending mechanism,a faster catenary mechanism,and a lower resistance.

关 键 词：冷弯薄壁型钢 梁柱节点 连续性倒塌 断裂 有限元分析 

分 类 号：TU391[建筑科学—结构工程] TU312.3