C30再生粗骨料混凝土和易性和抗压强度研究

Study on the workability and compressive strength of C30 recycled coarse aggregate concrete

以砖混结构建筑拆卸下来的混凝土块为原材料制备C30再生粗骨料混凝土,利用正交设计方法,研究了再生粗骨料取代率、水灰比、砂率对再生混凝土28 d抗压强度及和易性的影响。结果表明再生粗骨料取代率是影响混凝土28 d抗压强度及和易性的最主要因素;随着再生粗骨料取代率的增加,强度与和易性均下降;使再生粗骨料取代率为60%,水灰比为0.5,砂率为36%,通过合理的配合比可以配制出28 d强度达到46.3 MPa的混凝土。

The C30 recycled coarse aggregate concrete is produced by use of the concrete blocks from the dismantled masonry structure buildings and the influence of recycled coarse aggregate replacement percentages, water cement ratio, and sand ratio on the 28 d compressive strength and workability are studied in orthogonal experiment design. The results show that the recycled coarse aggregate replacement percentages is the most primary factor effecting on 28 d compressive strength and workability; and with the recycled coarse aggregate replacement percentages increased, strength and workability decreased; It calls for using the percentages of 60% as recycled coarse aggregate,0.5 as water cement ratio and 36% as sand ratio to make reasonable design of mix proportions, we can obtain the recycled coarse aggregate concrete that its 28d compressive strength reach to 46.3 MPa.