考虑现浇楼板影响的RC框架梁板柱协同抗连续性倒塌非线性有限元分析  

Nonlinear finite element analysis on beam-slab-column synergistic progressive collapse resistance of RC frame considering the effect of cast-in-place slabs

作　　者：贾益纲 詹鸣晨 吴光宇 敖居明 王惠宾 JIA Yigang;ZHAN Mingchen;WU Guangyu;AO Juming;WANG Huibin(Design and Research Institute,Nanchang University,Nanchang 330047,China;School of Civil Engineering and Architecture,Nanchang University,Nanchang 330031,China)

机构地区：[1]南昌大学设计研究院,南昌330047 [2]南昌大学建筑工程学院,南昌330031

出　　处：《建筑结构》2022年第6期61-68,共8页Building Structure

基　　金：国家自然科学基金研究计划项目(51268044)。

摘　　要：为深入考察现浇楼板对RC框架结构抗连续性倒塌性能的影响,先对一2层带板框架静力坍塌试验进行仿真模拟,校核三维实体退化虚拟层合单元模拟分析法的准确性;通过对比空间4层框架底层有无楼板的情况,分析了结构在底层为独立梁格状态和肋梁楼盖状态下倒塌过程中的破坏形态与钢筋应力变化,得出肋梁楼盖结构中贯通梁因梁板协同效应并未像在独立梁格中触发“悬链线”机制;通过改变该空间框架底层板厚的情况,分析了不同板厚模型连续倒塌过程中不同的破坏形态与抗力表现,发现各模型贯通梁格区楼板均以失效柱为中心呈“花瓣形”薄膜受拉状态,随板厚增加薄膜受拉区逐渐回拢,应力等值线渐变稀疏,结构承载力相应提高。In order to deeply investigate the effect of cast-in-place slabs on the performance of RC frame structure against progressive collapse,the accuracy of the simulation analysis method based on degenerated 3 D solid virtual lamination element was verified first through the simulation of the static collapse test of a two-story frame with slabs.By comparing situations whether there were floor slabs on the ground floor of a spacial 4-story frame,the failure form and the stress change of steel rebars during the collapse process of the structure when the ground floor was a beam-only grid or a ribbed-beam floor were discussed,and it was concluded that the through-beam in the ribbed-beam floor had not triggered“catenary”mechanism like in the beam-only grid floor due to the beam-slab synergistic effect.By changing the slab thickness on the ground floor of the spacial frame,the failure form and resistance performance of models with different slab thickness were analyzed,it was found that slabs within the through-beam lattice area of each model were in a“petal-shaped”tensile membrane action centered on the failed column;with the increase of slab thickness,the tensile membrane zone gradually converges,the stress contours gradually became sparse and the structural bearing capacity increases accordingly.

关 键 词：RC框架结构 连续性倒塌 三维实体退化虚拟层合单元 悬链线机制 花瓣形拉力膜 

分 类 号：TU375[建筑科学—结构工程]