角柱失效下钢筋混凝土梁-板子结构的抗连续倒塌性能研究  

Behavior of reinforced concrete beam-slab substructure to resist progressive collapse under loss of a corner column scenario

作　　者：沈春盛 Shen Chunsheng(Operation Management Department,East China Regional Headquarters,China Railway Construction Corporation,Hangzhou 310000,China)

机构地区：[1]中国铁建股份有限公司华东区域总部运营管理部,浙江杭州310000

出　　处：《建筑科学》2022年第11期60-67,共8页Building Science

基　　金：国家自然科学基金(51568004)。

摘　　要：为了研究角柱失效下钢筋混凝土(RC)梁-板子结构的抗连续倒塌性能,本文采用有限元软件ANSYS/LS-DYNA对角柱失效工况下的梁-板子结构拟静力试验建立精细化有限元模型,并通过试验结果校核了竖向荷载-位移曲线和破坏模式的准确性。在已验证的有限元模型的基础上,研究了混凝土强度、角柱配箍率以及荷载重分配机理对所研究子结构的抗连续倒塌性能的影响。有限元分析表明:混凝土强度的提高减轻了结构的破坏程度,混凝土强度为50MPa时结构的第一峰值荷载相较20MPa的第一峰值荷载提高了82.0%。角柱配置箍筋延迟了角柱的剪切破坏,并提高了结构的承载能力。在大变形阶段,楼板的拉膜机制可明显提高结构的承载能力和变形能力,带板框架的第一峰值荷载相比纯框架的提高了65.9%。In order to study the progressive collapse performance of reinforced concrete(RC) beam-slab substructure under loss of a corner column, the finite element software ANSYS/LS-DYNA is used to establish a finite element model for quasi-static test of beam-slab structures under the failure of corner colums, and the accuracy of the vertical load-displacement curves and failure mode is checked by comparing the test results. Based on the validated finite element model, the influence of concrete strength, stirrup ratio of corner column and load redistribution mechanism to the progressive collapse performance of substructure is analyzed. The FEA results show that with the increase of concrete strength, the damage degree of the structure is weakened. When the concrete strength is 50 MPa, the first peak load of the structure increases by 82.0% compared with that of 20 MPa. The stirrups reinforced designed on the corner column can delays the shear failure of the corner column and improves the bearing load capacity of the structure. In the stage of large deformation, the tensile membrane action of the slab can obviously improve the bearing load capacity and deformation capacity of the structure. The first peak load of plate frame is 65.9% higher than that of pure frame.

关 键 词：梁-板子结构 有限元分析 荷载重分配机理 连续倒塌 变形能力 

分 类 号：TU398[建筑科学—结构工程]