压剪破坏过程中混凝土的储能规律

Energy Storage Law of Concrete During Compression and Shear Failure

为了考察混凝土压剪破坏过程中的储能规律,利用10 MN的大型多功能液压伺服三轴仪,通过设置不同应变速率(10^(-5)、10^(-4)、10^(-3)/s)及不同法向压应力(15、20、25、30、35 MPa)对混凝土试件进行压剪试验。采用能量法计算混凝土内部的总能量、弹性能和耗散能,并分析混凝土的总能量与弹性能之间的相互关系。结果表明,不同法向压应力下,混凝土试件的总能量、弹性能、耗散能均随剪切位移的增加呈非线性增长趋势;对于混凝土峰前阶段,不同应变速率下混凝土的总能量与弹性能之间呈线性关系,且混凝土的储能系数随法向压应力的增加而增强,随应变速率的增大而减弱。这为从能量角度研究混凝土的破坏规律提供了理论依据。

In order to investigate the law of energy storage in the process of concrete compression and shear failure, a 10 MN large multi-functional hydraulic servo triaxial instrument was used to carry out compression and shear test of concrete specimens by setting different strain rates(10^(-5)、10^(-4)、10^(-3)/s)and different normal compressive stresses(15, 20, 25, 30, 35 MPa). The energy method was adopted to calculate the total energy, elastic energy and dissipated energy of concrete, and the relationship between the total energy and elastic energy of concrete was analyzed. The results show that the total energy, elastic energy and dissipated energy of concrete specimens increase nonlinearly with the increase of shear displacement under different normal compressive stresses. For the pre-peak stage of concrete, there is a linear relationship between the total energy and elastic energy of concrete at different strain rates, and the energy storage coefficient of concrete increases with the increase of normal compressive stress, but decreases with the increase of strain rate. The research method provides a theoretical basis for studying the failure law of concrete from the perspective of energy.