自密实再生混凝土的基本力学性能试验研究

为了研究自密实再生混凝土的基本力学性能，通过立方体抗压强度试验、轴心抗压强度试验、劈裂抗拉强度试验和弹性模量试验，观察了自密实再生混凝土的受压和受拉破坏过程和破坏形态，分析了再生粗骨料替代率对自密实再生混凝土基本力学性能的影响，探讨了普通混凝土和再生混凝土的各力学性能指标之间的换算关系对自密实再生混凝土的适用性. 结果表明:自密实再生混凝土受压和受拉的破坏形态与普通混凝土相似；当再生粗骨料替代率由0增加至100%时，自密实再生混凝土的立方体抗压强度、轴心抗压强度、劈裂抗拉强度和弹性模量分别降低了15.5%、12.7%、25.6%和11.5%，而自密实再生混凝土的峰值应变增大了19.8%；再生粗骨料替代率对自密实再生混凝土的泊松比无显著影响；普通混凝土和再生混凝土的各力学性能指标之间的换算关系不适用于自密实再生混凝土，提出的自密实再生混凝土的立方体抗压强度与其他力学性能指标之间的换算关系具有较高精度. 

Experimental Investigation of Basic Mechanical Properties of Self-Compacting Recycled Aggregate Concrete

In order to study the basic mechanical properties of the self-compacting recycled aggregate concrete（SCRAC）, the cubic compressive strength test, the axial compressive strength test, the splitting tensile strength test, and the elastic modulus test were carried out. The failure process and the failure mode of the SCRAC under compression and tension were observed. The effects of the recycled coarse aggregate（RCA）replacement ratio on the basic mechanical properties of the SCRAC were analyzed. The applicability of the conversion relationship between each mechanical property index of the ordinary concrete and the recycled aggregate concrete to the SCRAC was discussed. The test results show that the failure mode of the SCRAC under compression and tension is similar to that of the ordinary concrete. The test results also show that the cubic compressive strength, the axial compressive strength, the splitting tensile strength, and the elastic modulus of the SCRAC decrease by 15.5%, 12.7%, 25.6%, and 11.5%, respectively, and the peak strain of the SCRAC increases by 19.8%, when the RCA replacement ratio increases from 0 to 100%. The test results also demonstrate that RCA replacement ratio has no significant effect on the Poisson ratio of the SCRAC. The research findings indicate that the conversion relationship between each mechanical property index of the ordinary concrete and the recycled concrete is not applicable to the SCRAC, and the proposed conversion relationship between the cubic compressive strength and the other mechanical property indices of the SCRAC has high precision.