EFFECT OF MIXING PROCESS ON THE PERFORMANCE OF RECYCLED AGGREGATE CONCRETE

Five mixing processes of producing recycled concrete were considered,including cement paste soaking recycled coarse aggregate process,whose water-cement ratio is 0.50,025,and cement paste dosage is only half.The other two processes are traditional process and two-stage mixing process.The performance of recycled concrete produced by them was measured.It was found that the first mixing process could indistinctively improve 28 d compressive strength of recycled concrete,instead of the strength of 56 d reduced,the splitting tensile strength of the two ages were both relatively low,moreover,the discreteness of compressive strength was big;the compressive and tensile strengths of recycled concrete produced by the second mixing process were the lowest,moreover,the discreteness of strength was big;the both of strength produced by the third mixing process was higher than that of the former two,but the discreteness of strength was less than that of the former two,but bigger than that of the latter two.The two-stage mixing process could not only improve the compressive strength and splitting tensile strength of recycled concrete but also improve its working performance.Meanwhile,the discreteness of the strength of concrete made by this way is small.The recycled concrete produced by the traditional process also shows high compressive strength,high tensile strength and low discreteness of strength and this process is quite simple.