不同类型再生细骨料对保温混凝土力学性能的影响

为了研究不同类型再生细骨料对玻化微珠保温混凝土力学性能的影响,将废弃混凝土再生细骨料和废弃黏土砖再生细骨料分别以25%、50%、75%和100%(体积分数)取代率取代保温混凝土中的天然河砂,并测试了再生保温混凝土的抗压强度、劈裂抗拉强度和弹性模量。结果表明: 25%是废弃混凝土再生细骨料在保温混凝土中的最优取代率;75%是废弃黏土砖再生细骨料在保温混凝土中的最优取代率。再生细骨料的压碎值和再生胶砂强度比在实际工程中可以有效区分不同类型再生细骨料的品质。废弃黏土砖再生细骨料中的火山灰材料可以有效提高再生保温混凝土的密实度,而废弃混凝土再生细骨料中残余的氢氧化钙却降低了再生保温混凝土的力学性能,因而废弃黏土砖再生细骨料具有更高的回收利用价值。

Effects of Different Types of Recycled Fine Aggregate on Mechanical Properties of Thermal Insulation Concrete

In order to study the influence of different types of recycled fine aggregate on the mechanical properties of glazed hollow bead thermal insulation concrete, the natural river sand in thermal insulation concrete were replaced by recycled fine aggregate of waste concrete and recycled fine aggregate of clay brick at 25%, 50%, 75% and 100% (volume fraction) replacement ratio, respectively. And the recycled aggregate thermal insulation concrete compressive strength, splitting tensile strength and modulus of elasticity were measured. The experimental results show that 25% is the optimal replacement rate of recycled fine aggregate of waste concrete in thermal insulation concrete.75% is the optimal substitution rate of recycled fine aggregate of waste clay brick in thermal insulation concrete. Crushing value of recycled fine aggregate and strength ratio of recycled mortar effectively distinguish the quality of different types of recycled fine aggregate in practical engineering. The volcanic ash material in the recycled fine aggregate of the waste clay brick effectively improves the compactness of the recycled aggregate thermal insulation concrete, while the residual calcium hydroxide in the recycled fine aggregate of the waste concrete reduces the mechanical properties of the recycled aggregate thermal insulation concrete, so the recycled fine aggregate of the waste clay brick has higher recycling value.