双掺再生骨料混凝土工作性及力学性能试验研究

Experimental Research on Workability and Mechanical Properties of Double-admixing Recycled Aggregate Concrete

为了解决环境污染与资源紧张的问题,利用建筑垃圾中的废弃混凝土制备再生粗骨料和再生细骨料,分别按照不同的取代率替代天然骨料以双掺的形式制备再生混凝土。研究结果表明,双掺再生骨料混凝土的工作性及力学性能要差于天然骨料混凝土;随着再生细骨料和再生粗骨料取代率的增大,其用水量显著增多,各个龄期的抗压强度逐渐降低,但这两种性能均呈现出较好的线性关系;当双掺再生骨料的取代率均达到100%时,相比天然骨料混凝土,其用水量增多22.1%,抗压强度降低19.2MPa,线性相关系数均在0.942以上;再生混凝土应用时,双掺再生骨料的取代率均不宜大于50%。

In order to solve the problem of environmental pollution and resource shortage, the recycled coarse aggre- gate and recycled fine aggregate were used to prepare the recycled concrete by the waste concrete in tile construction waste, and it was prepared by replacing natural aggregate with different replacement ratio in the form of double-admixing. The research results show that, the workability and mechanical properties of the double-admixing recycled aggregate conete are worse than that of natural aggregate concrete. With the increase of the replacement ratio of recycled fine aggregate and recycled coarse aggregate, the water consumption of the concrete is increased significantly, and the compressive strength of each age is reduced gradually, but the two kinds of properties show a good linear relationship. When the replacement ratio of recycled aggregate is 100%, compared to the natural aggregate concrete, its water consumption increased by 22.1%, the compressive strength decreased by 19.2MPa, and the linear correlation coefficient is above 0.942. In the application of recycled concrete, the replacement ratio of double-admixing recycled aggregate should not be greater than 50%.