橡胶再生混凝土和易性试验研究

摘要

取再生粗骨料取代率为20％，用粒径0．55～2．36 mm橡胶颗粒等体积置换砂配制橡胶再生混凝土，通过混凝土坍落度试验研究了橡胶粒掺量、橡胶粒改性方式和粉煤灰掺量对混凝土拌合物和易性的影响规律。结果表明：掺橡胶粒的混凝土拌合物的流动性大于未掺橡胶粒的混凝土，且随着橡胶粒掺量的增加，混凝土拌合物的流动性逐渐增强；NaOH与KH-550复合改性混凝土拌合物的流动性最大，其他改性与未改性混凝土拌合物的流动性几乎相当；粉煤灰能够提高混凝土拌合物的流动性，由于超叠效应，复掺粉煤灰和橡胶粒的混凝土拌合物的流动性大幅度提高；橡胶再生混凝土拌合物具有良好的黏聚性和保水性。%Rubber-recycled concrete was mixed with recycled aggregates at a rate of 20%and crumb rubbers with size of 0.55~2. 36mm which replace sands at the same volume.Through the slump test,the effect of rubber rates,rubber modification method and fly ash rates on workability of rubber-recycled concrete was studied. The results show that the fluidity of rubber-recycled concrete mixture is larger than recycled concrete,with the increase of rubber rate,the fluidity increases gradually. The fluidity of concrete mixture modified by NaOH and KH-550 composite is largest,the other modified and unmodified concrete almost equal. Fly ash can improve the fluidity of concrete mixture,due to synergistic effect,the fuidity of concrete mixture mixed with fly ash and rubber improves greatly. Rubber-recycled concrete mixture has good adhesiveness and water retention.