再生粗骨料强化处理方式对再生混凝土抗碳化性能的影响

Effect of enhanced processing mode properties of recycled coarse aggregate on the carbonation resistance of recycled concrete

再生粗骨料内部裂缝较多,压碎指标值偏大,使其骨料品质较差,导致配制的再生混凝土的抗碳化性能较低。废弃混凝土经简单破碎、一次颗粒整形和二次颗粒整形强度处理后分别制得三类颗粒整形再生粗骨料;将三类颗粒整形再生粗骨料在浓度6%的有机硅烷防水剂中进行24 h浸渍处理,得到三类颗粒整形有机硅烷浸渍再生粗骨料。研究经颗粒整形和有机硅烷浸渍不同强化方式处理的再生粗骨料对再生混凝土抗碳化性能的影响,试验表明:再生混凝土的抗碳化性能随颗粒整形次数的增加而增强,并逐渐接近天然骨料制备的普通混凝土的抗碳化性能;再生粗骨料颗粒整形的次数一定,经过有机硅烷浸渍会进一步增强再生混凝土的抗碳化性能,并且三类颗粒整形有机硅烷浸渍的再生粗骨料混凝土抗碳化性能都高于天然骨料制备的普通混凝土的抗碳化性能。

Recycled coarse aggregate＇s internal cracks are more and crushing index value is too large, so that the aggregate quality is poor, resulting in anti carbonation performance of the recycled concrete is low.Three kinds of particle shaping recycled coarse aggregate were prepared with waste concrete crushing simply, a particle shaping strength treatment and secondary particle shaping strength treatment. Three types of particle shaping regeneration coarse aggregate in 6% concentration of organic silane waterproof agent for 24 h impregnation treatment to become three kinds of particle shape organic silane impregnation of recycled coarse aggregate.Study recycled coarse aggregates of the particle shaping and organic silane impregnation of different enhancement process have effect on the recycled concrete carbonation resistance.The tests show that the recycled concrete carbonation resistance with the increase of the number of particle shaping enhanced and gradually close to the carbonation resistance of ordinary concrete of natural aggregate preparation.Recycled coarse aggregate particle shaping a certain number of times,being impregnated with organic silane will further enhance recycled concrete carbonation resistance, and three kinds of particle shaping organic silane impregnation of recycled coarse aggregate concrete carbonation resistance are higher than that of natural aggregate preparation of ordinary concrete carbonation resistance.