再生细骨料混凝土力学特性研究

Study on mechanical properties of recycled fine aggregate concrete

为了深入理解再生细骨料如何影响混凝土的力学性能,并推动再生细骨料混凝土在实际工程中的广泛使用,本研究通过系统分析再生细骨料混凝土与天然骨料混凝土在抗压、抗拉等关键力学性能方面的对比,揭示利用再生细骨料制备混凝土时其强度和耐久性的变化规律。采用统一水灰比,对两种材料的3d及后期龄期进行了测试,试验结果显示,在相同水灰比下,再生细骨料混凝土的28d抗压强度低于天然骨料混凝土约15%,但随时间推移两者差异逐渐减小。对于劈裂抗拉强度,再生细骨料混凝土在3d的抗拉强度约为天然骨料混凝土的83%,且这一数值在随后的测试中稳定在约85%。此外,再生细骨料混凝土的静力弹性模量在3d时为天然骨料混凝土的86.7%,随着养护时间的增加,该比例略有上升,达到了大约93%。

In this study,the comparison of key mechanical properties such as compressive and tensile strength of recycled fine aggregate concrete and natural aggregate concrete is systematically analyzed,and the variation law of strength and durability of recycled fine aggregate concrete is revealed.The results show that the 28d compressive strength of recycled fine aggregate concrete is about 15%lower than that of natural aggregate con-crete under the same water-cement ratio,but the difference between the two materials gradually decreases with time.For splitting tensile strength,the tensile strength of recycled fine aggregate concrete in 3d is about 83%of that of natural aggregate concrete,and this value has stabilized at about 85%in subsequent tests.In addi-tion,the static elastic modulus of recycled fine aggregate concrete is 86.7%of that of natural aggregate con-crete at 3d,and the proportion increased slightly with the increase of curing time,reaching about 93%.