温度对全再生混凝土三轴受压性能及破坏准则影响

Influence of Temperature on the Triaxial Compressive Behavior and Failure Criterion of Recycled Aggregate Concrete

为研究温度对全再生混凝土三轴受压力学性能及破坏准则的影响,设计制作了30个经不同温度后的全再生混凝土试件进行了三轴受压试验.研究表明:单轴应力条件下,随着温度上升,试件裂缝破碎带变宽;三轴应力条件下,随着温度上升,试件破坏形态由斜面剪切破坏向层状劈裂破坏转变.其次,随着温度上升,抗压强度、弹性模量均呈逐渐下降趋势,但峰值应变则呈逐渐上升的变化趋势;相对于单轴受压状态,温度影响明显减小.最后,根据过镇海模型和M-C理论,分别给出了峰值应力、峰值应变及弹性模量与温度之间的相互关系式,以及M-C理论包络曲线方程.

To study the influence of temperature on the triaxial compressive behavior and failure criterion of recycled aggregate concrete,30 specimens with 100%replacement ration after different temperatures were designed under triaxial compressive test.The results show that the crack fracture zone of specimens will be wider with the increase of temperature under uniaxial compressive condition.The failure forms of specimens will change from cant shear to flake splitting with the increase of temperature under triaxial compressive condition.Furthermore,with the increase of temperature,both compressive strength and elastic modulus will decrease gradually,but peak strain will increase gradually.Compared to unaxial stress condition,the influence of temperature will decrease obviously.Lastly,according to the model of Guo Zhenhai and M-C theory,the relationship between peak stress,peak strain,elastic modulus and temperatures were given,respectively,and the M-C theoretical envelope curve equation was given.