考虑尺寸效应影响的箍筋约束混凝土应力-应变本构关系模型  

Stress-strain constitutive model of concrete confined by hoops with considering size effect

作　　者：宋佳[1,2] 李振宝[3] 王元清[2] 左勇志[4] 

机构地区：[1]北京建工集团有限责任公司博士后科研工作站,北京100055 [2]清华大学土木工程系,北京100084 [3]北京工业大学城市与工程安全减灾教育部重点实验室,北京100124 [4]北京市建筑工程研究院有限责任公司,北京100039

出　　处：《建筑结构学报》2015年第8期99-107,共9页Journal of Building Structures

基　　金：中国博士后科学基金项目(2014M560880);国家自然科学基金项目(50838001)

摘　　要：为了考察约束混凝土轴压力学性能的尺寸效应,对两个系列的圆形箍筋约束混凝土圆柱试件进行了单调轴压试验,主要试验变量为体积配箍率和试件几何尺寸,试件的最大直径为576 mm。试验结果表明,约束混凝土的峰值应力和峰值应力对应应变均随试件尺寸的增大呈下降趋势,而变形能力与试件尺寸的关系不够明确。利用析因分析法对试验数据进行分析,发现体积配箍率对箍筋约束混凝土的峰值应力、峰值应力对应应变和变形能力均有显著影响。试件几何尺寸对峰值应力及对应应变的影响较为显著,但对试件变形能力的影响不明显。体积配箍率与试件几何尺寸的交互作用对峰值应力、峰值应力对应应变和变形能力的影响均不显著。基于试验、分析结果,建立了针对圆形箍筋约束混凝土的应力-应变本构关系模型,模型预测值与本文试验结果吻合较好。A monotonic axial compression test was performed on two series of short column specimens in order to investigate the size effect of axial compressive mechanical properties of confined concrete. The main test variables were volumetric ratio of stirrup and specimen size. The diameter of largest specimen was 576 mm. The test result shows that as the specimen size increases,the peak stress and the peak strain of confined concrete decreases. The relationship between ductility and specimen size is indistinct. When factorial analysis method is used to analyze the test results,it can be found that the volumetric ratio of stirrup has significant influence on peak stress,peak strain and ductility of confined concrete. The specimen geometric size affects peak stress and peak strain significantly,but no great influence on ductility. The interaction of volumetric ratio and geometric size does not affect peak stress,peak strain and ductility too much. Based on the test and the analysis results,a stress-strain constitutive model in terms of column confined by hoops is established. Its prediction value fits well with the test result of this thesis.

关 键 词：约束混凝土 尺寸效应 轴压试验 析因分析法 应力-应变本构关系模型 

分 类 号：TU528.1[建筑科学—建筑技术科学]