自密实再生骨料混凝土试验研究

Experimental study of self-compacting concrete made with recycled aggregate

采用正交试验设计方法优选自密实再生骨料混凝土配合比参数,研究粉煤灰掺量、砂率、再生骨料掺量和水灰比对自密实再生骨料混凝土性能的影响。试验结果表明:影响自密实再生骨料混凝土工作性能的各因素的顺序依次为:水灰比>砂率>粉煤灰掺量>再生骨料掺量;影响7 d抗压强度的各因素的顺序依次为:粉煤灰掺量>水灰比>砂率>再生骨料掺量。在正交试验的基础上,综合考虑混凝土强度和工作性能要求,优选出自密实再生骨料混凝土配合比参数:再生骨料掺量80%,粉煤灰掺量30%、砂率45%、水灰比0.30,通过验证试验表明该配合比配制的自密实再生骨料混凝土工作性能和强度满足C40自密实混凝土要求。

The mixture ratio parameters of self-compacting concrete made with recycled aggregate is optimized,using orthogonal experiment design method.The influence of pulverized coal ash, sand rate,regeneration aggregate and W/B are researched.The test results indicate that the order of factors which influence operating performances of self-compacting concrete made with recycled aggregate is W/B〉sand rate〉pulverized coal ash〉regeneration aggregate ;while the order of factors influencing 7days compressive strength is pulverized coal ash〉W/B〉sand rate〉regeneration aggregate.Based on orthogonal experiment,and considering the request of concrete intensity and operating performance,the mixture ratio parameters of self-compacting concrete made with recycled aggregate is optimized： 80% of regeneration aggregate, 30% of pulverized coal ash, sand rate 45%, W/B=0.30.The verification test indicates the operating performance and intensity of self-compacting concrete made with recycled aggregate which is produced On the optimized mixture ratio parameters, satisfies the request of C40 self-compacting concrete.