再生骨料对再生混凝土基本性能的影响

Influence of Recycled Aggregate on Basic Properties of Recycled Concrete

试验测定了再生骨料的各项技术指标,以及在不同再生骨料取代率下的再生混凝土的坍落度、强度等技术指标.通过对试验数据进行分析,得出下以结论:再生骨料的各项物理技术性能比天然骨料有一定程度降低,但满足GB/T25177-2010规定要求,可用于再生混凝土.再生骨料吸水率大,在再生混凝土配合比设计用水量的确定时应充分考虑.随着再生骨料取代率增加混凝土坍落度在减小.再生混凝土强度也与再生骨料取代率密切相关,当取代率为40%时,强度降低幅度较小;当取代率达100%时,强度下降明显,因此配制再生混凝土时,控制再生骨料取代率是关键因素.

The paper determined main technical indexes of recycled aggregate,as well as several indexes of recycled concrete like slump and strength under different aggregate replacement rates.Based on the analysis of experimental data,we can conclude that all physical technical properties of recycled aggregate are lower than those of natural aggregate to some extent,but they meet specified re-quirements of GB/T25177 -2010.Recycled aggregate has great water absorption which should be fully considered when identifying the water consumption of the concrete.As the replacement rate of recycled aggregate increases,the slump of concrete decreases.The con-crete strength is also strongly coupled with the aggregate replacement rate,and the strength decrease is relatively small when the re-placement rate is 40%;it has a evident decline when the replacement rate reaches 100%.Therefore,controlling the replacement rate is the key factor while making up the recycled concrete.