再生粗集料的循环利用对混凝土性能影响研究

Effects of Recycling of Recycled Coarse Aggregate on Concrete Properties

试验以混凝土强度等级、再生粗集料反复循环利用次数以及再生粗集料取代率为变量,探索了低品质再生粗集料经反复再生利用后对混凝土性能的影响,并与普通混凝土进行了对比。试验结果表明,随着粗集料循环再生利用次数的增加,同一配比、同一强度等级新拌再生混凝土的坍落度值有所降低,坍落度经时间损失值也越大;随着再生粗集料循环利用次数的增加,同一种强度等级、同一种再生粗集料取代率再生混凝土的抗压强度逐渐降低;再生混凝土的强度越低,弹性模量越小;与普通混凝土相比,相同强度等级再生混凝土弹性模量普遍低于普通混凝土,且再生粗集料循环利用次数越多,混凝土弹性模量降低也越明显。

Use concrete strength grades、recycling times of recycled coarse aggregate and recycled coarse aggregate replacement ratios as variables in the test,study effects of low-quality recycled coarse aggregate after repeated recycling on the properties of concrete,and compare with the ordinary concrete. The results show that,with the increase of recycling times of recycled coarse aggregate,the slump of fresh recycled concrete which has the same ratio、same strength grade reduces a bit,but the slump loss is greater over time; As the increase of recycling times of recycled coarse aggregate,the compressive strength of recycled concrete which has the same strength grade、same recycled coarse aggregate replacement ratio reduces gradually; The lower of recycled concrete,the elastic modulus is lower;compared with the ordinary concrete; the elastic modulus of recycled concrete which has the same strength grade is generally lower than that of ordinary concrete,and as the recycling times of recycled coarse concrete increase,the elastic modulus reduces more obviously.