钢套管混凝土加固RC柱轴压受力全过程分析  

Analysis on Behavior of Square RC Columns Strengthened with Concrete Filled Steel Tube Under Axial Load

作　　者：殷晓三[1] 梁鸿骏[2] 卢亦焱[2] 李娜[3] YIN Xiaosan;LIANG Hongjun;LU Yiyan;LI Na(School of Architecture and Civil Engineering,Zhongyuan University of Technology,Zhengzhou 451191,China;School of Civil Engineering,Wuhan University,Wuhan 430072,China;Wuhan University of Technology,Wuhan 430072,China)

机构地区：[1]中原工学院建筑工程学院,河南郑州451191 [2]武汉大学土木建筑工程学院,湖北武汉430072 [3]武汉理工大学,湖北武汉430072

出　　处：《应用基础与工程科学学报》2022年第3期566-578,共13页Journal of Basic Science and Engineering

基　　金：国家自然科学基金项目(51878520);湖北省自然科学基金项目(2016CFB271)。

摘　　要：对9个钢套管混凝土加固RC方柱和1个RC对比柱进行轴心受压试验,试验结果表明采用钢管混凝土加固后,RC柱的承载力平均提高3.65~5.39倍,破坏形态呈延性破坏,破坏后荷载仍然可以保持在较高水平.基于钢套管混凝土加固RC方柱轴压试验的研究结果,合理选择材料本构关系、钢-混凝土界面接触关系和混凝土单元破坏的准则,采用有限元软件ANSYS建立加固柱轴心受压力学模型,对轴压作用下加固柱的受力全过程进行计算分析.通过对比试验测得的和计算的试件承载力和荷载-纵向变形全过程曲线,发现二者吻合良好,最大误差仅为5%.在此基础上,利用被验证的有限元计算模型,对试件各个组成部分的应力分布和应力发展规律进行分析.结果表明,试件各个组成部分在加载初期持荷比例基本不变;随着荷载的继续增加,钢管对原RC方柱和后浇筑混凝土产生明显的约束作用,使其峰值应力明显超过单轴抗压强度,钢管持荷比例小幅度减小,而混凝土持荷比例小幅度增大;当试件达到承载力之后,由于钢管的硬化和混凝土被压碎,钢管持荷百分比增大.The behavior of 1 referenced RC column and 9 RC columns strengthened with concrete filled steel tube under axial load were tested.The experimental results show that the bearing capacity of RC column increases by 3.65~5.39 times on average after strengthened.Moreover,the strengthened columns behave in a relatively ductile manner,and the applied load maintains at a certain loading level after the ultimate load.Based on the test data,3-D finite element models established by ANSYS were applied to analyze the behavior of the specimens under axial load.Appropriate material stress-strain relations and failure criteria were considered.The ultimate loads and load-longitudinal deformation curves of test specimens were calculated and compared with the experimental results.It is found from the comparison that the calculation value agrees well with the experimental value,and the maximum error of calculated strengths is 5%.Additionally,the stress distributions of test specimens under the axial loading were analyzed by the verified models.The analysis results show that the load ratio of each component is unchanged at the initial stage of loading.As the load continues to increase,the steel tube shows obvious confinement on the RC column and post-cast strengthening concrete so that their peak stress significantly exceeds the uniaxial compressive strength.Therefore,the load proportion of steel tube decreases slightly,while the proportion of the concrete bearing load increases slightly.When the specimen reaches the ultimate load,the proportion of the steel tube bearing load increases due to the hardening of the steel tube and the crushing of the concrete.

关 键 词：钢套管混凝土 加固 钢筋混凝土方柱 有限元分析 轴压性能 轴心受压试验 

分 类 号：TU375.3[建筑科学—结构工程]