高强高性能混凝土三轴拉压压力学性能试验研究

EXPERIMENTAL STUDY ON THE MECHANICAL BEHAVIOR OF HIGH STRENGTH AND HIGH PERFORMANCE CONCRETE UNDER TRIAXIAL COMPRESSIVE-TENSILE LOADING

采用大型动静真三轴伺服液压试验系统,对单轴压强度为90.6 MPa的高强高性能混凝土进行三轴拉压压等比例试验研究,获得了各应力比下试件的破坏模式、多轴强度及应力-应变曲线。试验结果表明:高强高性能混凝土三轴拉压压应力状态下的破坏为典型的受拉破坏;最大主应力方向的极限强度远低于其单轴压强度,中间主应力效应不明显;拉应力的存在对最大主应力方向应力-应变曲线影响十分明显,呈现出明显的线性特征。基于试验结果提出了适用于高强高性能混凝土的强度准则,为高强高性能混凝土本构关系的建立提供了试验和理论依据。

An experimental investigation was conducted to characterize the responses of high strength and high performance concrete(HS-HPC)subjected to triaxial compressive-tensile stresses with servo-hydraulic actuators at different stress ratios.The uniaxial compressive strength of HS-HPC is 90.6 MPa.The principal stresses and strains of the specimens were recorded,and the failure of the specimens under various stress states were examined.The experimental results indicate that the typical failure mode of the specimens is tensile failure.The ultimate stress in maximum principal stress direction is much lower than uniaxial compressive strength,and the intermediate principal stress effect is not obvious at different stress ratios.The presence of tensile stress has significant influence on the stress-strain curve in maximum principal stress direction,which shows obvious linear characteristics compared with uniaxial compressive stress state.Failure criteria are proposed for the HS-HPC specimens under triaxial compressive-tensile loading.The test results provide a valuable reference for obtaining multi-axial constitutive law for HS-HPC.