再生砖粉掺量对混凝土性能的影响

Effect of recycled brick powder content on the properties of concrete

为提高建筑固废中废砖的再生利用率,通过球磨法制备出再生砖粉,利用再生砖粉作为火山灰材料替代部分水泥,研究再生砖粉在取代率为5%、10%、15%、20%、30%、40%下对混凝土工作性能和力学性能的影响。结果表明:随着再生砖粉取代率的增加,混凝土拌合物的流动性逐渐降低,但再生砖粉掺量在20%以内的拌合物流动性降低幅度较小。掺再生砖粉混凝土具有与对照组混凝土相近的7 d抗压和抗弯拉强度,随着养护龄期的增长,掺再生砖粉混凝土的28 d抗压和抗弯拉强度在砖粉取代率为40%时较对照组混凝土分别降低了18.4%和18.7%。

In order to improve the recycling efficiency of brick waste,recycled brick powder was prepared by ball grinding method and used as pozzolanic material to replace part of cement.The effects of recycled brick powder on the work-ability and mechanical properties of concrete were studied when the replacement rate was 5%,10%,15%,20%,30%and 40%.The results showed that the work-ability of concrete mixture decreased gradually with the increase of the replacement rate of recycled brick powder,but the work-ability of the mixture with<20%recycled brick powder decreased slightly.The 7 d compressive strength and flexural strength of concrete containing recycled brick powder was similar to that of the control concrete.With the growth of curing age,the 28 d compressive strength and flexural strength of concrete containing 40%recycled brick powder decreased by 18.4%and 18.7%,respectively compared with the control concrete.