外套方钢管自密实混凝土加固RC方柱轴压性能受力分析  

Mechanical analysis on behavior of square RC columns strengthened with self-compacting concrete filled square steel tube under axial load

作　　者：廖健聪 卢亦焱[1] 李杉[1] 梁鸿骏[1] LIAO Jiancong;LU Yiyan;LI Shan;LIANG Ilongjun(School of Civil Engineering,Wuhan University,Wuhan 430072,China)

机构地区：[1]武汉大学土木建筑工程学院

出　　处：《混凝土》2019年第8期47-53,共7页Concrete

基　　金：国家自然科学基金项目(51078294);湖北省技术创新专项重大项目(2016AAA025)

摘　　要：在5根外套方钢管自密实混凝土加固RC方形截面短柱和2根未加固RC方形截面短柱轴压试验的基础上,采用大型有限元软件ABAQUS建立有限元计算模型,将计算得到的极限荷载和荷载-纵向位移曲线与试验结果进行对比,二者吻合良好。在此基础上,进行组合结构加固柱的轴压工作机理分析和参数分析,结果表明:钢管在组合结构加固柱达到极限荷载前就已屈服;原柱、钢管和新增混凝土持荷分配的变化规律与所处的加载阶段有关。提高新增混凝土强度,极限荷载下新增混凝土的持荷比例增大,原柱和钢管的持荷比例减小;增大钢管壁厚或提高钢管屈服强度,极限荷载下钢管的持荷比例增大,原柱和新增混凝土的持荷比例减小。Based on the experimental study of 5 RC columns strengthened by self-compacting concrete filled square steel tube and 2 unstrengthened RC columns subjected to axial load,a finite element mode built by ABAQUS was developed to analyze the mechanical properties of the composite strengthened columns under the axial load.The calculated ultimate bearing capacity and the load-longitudinal displacement curve were compared with the experimental results,and the two are in good agreement.On the basis of the verified model,the mechanismand the influential parameters of the strengthened columns under the axial load were analyzed,the results showed that the steel tube had yielded before the strengthened column reached the ultimate strength.The change rule of the load distribution between the original column,the steel tube and the strengthening concrete was related to the loading stage.Increasing the strength of strengthening concrete,the proportion of strengthening concrete bearing axial force increased under the ultimate load,and the proportion of original column and steel tube reduced.Increasing the thickness or the yield strength of steel tube,the proportion of steel tube bearing axial force increased under the ultimate load,and the proportion of original column and strengthening concrete reduced.

关 键 词：方钢管 自密实混凝土 加固 有限元 持荷分配 

分 类 号：TU528.59[建筑科学—建筑技术科学]