混凝土双轴受压试验与破坏准则研究  

Study on concrete biaxial compression test and failure criterion

作　　者：张军[1] 孙雪[2] 赵志青 ZHANG Jun;SUN Xue;ZHAO Zhiqing(Architecture Engineering Institute,Yangzhou Polytechnic Institute,Yangzhou 225127,China;Architecture Engineering Institute,Jinling Institute of Technology,Nanjing 211169,China;Engineering Management Department,Hohai University,Nanjing 211100,China)

机构地区：[1]扬州工业职业技术学院建筑工程学院,江苏扬州225127 [2]金陵科技学院建筑工程学院,江苏南京211169 [3]河海大学工程管理系,江苏南京211100

出　　处：《混凝土》2020年第5期45-48,共4页Concrete

基　　金：国家自然科学基金(51578478)。

摘　　要：利用岩石真三轴仪液压伺服机,采用定侧向加载方式对普通混凝土进行双轴受压试验研究,得到不同应力比下混凝土的应力-应变曲线和破坏形态,通过提取应力-应变曲线峰值应力和峰值应变(峰值应力对应应变)特征值,研究不同应力比下混凝土破坏机理与主应力方向的强度规律.试验结果表明:当侧向应力较小时,混凝土破坏形态与单轴受压向类似;当侧向应力较大时,试件呈现劈裂状破坏形态.当σX/fc=0~0.2时,峰值应力随着侧向应力比的增大而增大,当σX/fc=0.2~0.5时,σZ峰值应力随着侧向应力比的增大而变化较小.应用Kupfer破坏准则对试验数据进行验证,Kupfer破坏准则预测定侧向加载方式下混凝土双轴受压强度结果相对保守.同时基于Kupfer破坏准则方程提出了定侧向加载下混凝土的破坏准则并进行验证.研究结果对混凝土工程应用与计算具有较大的意义。Using the triaxial hydraulic servo machine,the lateral loading experiment of biaxial compression of ordinary concrete,get stress ratio under the concrete stress-strain curves and failure modes should be different,by extracting the peak value of stress-strain curve stress and peak strain(strain corresponding to the peak stress)of different feature value.The stress ratio of concrete failure mechanism and regularity of the principal stress direction.The test results show that when the lateral stress is small,the failure mode of concrete is similar to that of uniaxial compression.When the lateral stress is large,the specimen presents a splitting failure form.When σx/fc=0~0.2,the peak stress increases with the increase of lateral stress ratio.When σx/fc=0.2~0.5,the peak stress of σz decreases with the increase of lateral stress ratio.The Kupfer′s failure criterion is applied to verify the experimental data.Kupfer′s failure criterion predicts that the strength of concrete under biaxial loading is relatively conservative.At the same time,based on the Kupfer′s failure criterion equation,the failure criterion of concrete under fixed lateral loading is proposed and verified.The results are of great significance to the application and calculation of concrete engineering.

关 键 词：普通混凝土 定侧向加载 双轴受压 破坏准则 

分 类 号：TU528.01[建筑科学—建筑技术科学]