楼盖短梁受力性能试验与有限元分析  

Experiment study and finite element analysis on mechanical performance of floor short beams

作　　者：郑振光 韩小雷[1,2] 陈鑫凯 季静[1,2] 林静聪 Zheng Zhenguang;Han Xiaolei;Chen Xinkai;Ji Jing;Lin Jingcong(State Key Laboratory of Subtropical Building and Urban Science,South China University of Technology,Guangzhou 510640,China;School of Civil Engineering&Transportation,South China University of Technology,Guangzhou 510640,China)

机构地区：[1]华南理工大学亚热带建筑与城市科学全国重点实验室,广东广州510640 [2]华南理工大学土木与交通学院,广东广州510640

出　　处：《土木工程学报》2025年第1期47-57,共11页China Civil Engineering Journal

基　　金：国家自然科学基金(52178483);华南理工大学亚热带建筑科学国家重点实验室自主研究课题(2022KA02)。

摘　　要：为研究结构空间约束对楼盖短梁受力性能的影响,以楼盖短梁底筋配筋率和所处空间位置为变量,在框架结构中设计12根跨高比为3.3的楼盖短梁并进行竖向静力试验,并与4根相同参数的简支短梁试验结果进行对比。结果表明:楼盖短梁表现为首先发生纵筋屈服、最终沿临界斜裂缝劈裂,简支短梁表现为首先发生纵筋屈服、最终发生弯曲破坏或剪压破坏。与简支短梁相比,楼盖短梁承载力提高、延性降低。楼盖短梁承载力与底筋配筋率正相关,受空间位置的影响较小。建立试验框架的有限元模型进行数值模拟,结果显示:随着楼盖短梁截面所取的楼板翼缘宽度增大,轴压力沿梁跨分布趋于均匀。楼盖短梁所受轴向约束刚度增大时,轴力和承载力增大,承载力从受弯承载力控制转变为受剪承载力控制。采用我国规范承载力计算方法,分别按有无轴力计算楼盖短梁试件承载力,结果表明考虑轴压力才能准确判断破坏形态和计算承载力。To investigate the influence of structural spatial restraint on mechanical performance of floor short beams,12 floor short beams with a span-to-depth ratio of 3.3 were designed in a frame structure with the bottom reinforcement ratio and the spatial position of beam taken as variables,and then tested in static vertical loading tests.Furthermore,the test results were compared to those of 4 simply supported short beams with the same parameters.The research results indicate that for the floor short beams,the bottom longitudinal reinforcement yields firstly and eventually splitting along the critical diagonal crack occurs,while for the simply supported short beams,the bottom longitudinal reinforcement yields firstly and the beam fails in flexural mode or shear-compression mode eventually.Compared to the simply supported short beams,the capacity of the floor short beams is increased and the ductility is decreased.The capacity of the floor short beams is positively related to the bottom reinforcement ratio and is insensitive to the spatial position of beam.The finite element models of the test frame were established for numerical simulation,the simulation results disclose that with the increase of the floor flange width of the floor short beam section,the axial compressive force tends to be uniform along the beam span.When the axial restraint stiffness of the floor short beam increases,the axial force and capacity increase,and the capacity of the floor short beam changes from dominated by flexural capacity to dominated by shear capacity.By using the capacity calculation method suggested in Chinese code,the capacity of floor short beam specimens was calculated with and without the axial force being considered,respectively.It is shown that the axial compressive force shall be considered in order to accurately determine the failure mode and capacity of the floor short beams.

关 键 词：楼盖 短梁 结构空间约束 承载力 轴压力 

分 类 号：TU375.1[建筑科学—结构工程]