再生细骨料级配与微粉含量对CLSM工作性能的影响

Effects of recycled fine aggregate gradation and powder content on workability of controlled low-strength material

采用细度模数不同的7种级配和5级微粉含量再生细骨料制备可控性低强度材料(CLSM),测定了材料流动度和泌水率,研究再生细骨料级配与微粉含量变化对CLSM工作性能的影响并分析了再生细骨料不均匀系数C_u、曲率系数C_c和堆积密度与CLSM流动度及泌水率的关系。结果表明:当再生细骨料细度模数为2.98,微粉含量为8.0%时,CLSM具有较高流动度和较低泌水率。CLSM流动度和泌水率均随再生细骨堆积密度增大而提高并与再生细骨料堆积密度相关性较高,相关系数为相关系数为0.716 95和0.703 51。当再生细骨料细度模数大于2.82,微粉含量小于8.0%时,CLSM的1 h流动度大于200 mm;当再生细骨料细度模数为2.98,微粉含量为8.0%时,CLSM的1.5 h流动度大于200 mm。

Controllable low-strength materials(CLSM)were prepared by using 7 kinds of recycled fine aggregates with different gradations(different fineness modulus)and 5 kinds of recycled fine aggregates with different powder content,fluidity and bleeding of materials were measured,effect of recycled fine aggregate gradation and powder content on the workability of CLSM was studied and relationship between Coefficient of uniformity(Cu),Coefficient of curvature(Cc)and packing density of recycled fine aggregate and fluidity and bleeding of CLSM were analyzed.The results show that fineness modulus of recycled fine aggregate is 2.98 and powder content is 8.0%,CLSM has higher fluidity and lower bleeding.Fluidity and bleeding of CLSM are positively correlated with packing density of recycled fine aggregate,correlation coefficients are 0.71695 and 0.70351.Fineness modulus of recycled fine aggregate is greater than 2.82 and powder content is less than 8.0%,fluidity of CLSM is greater than 200 mm after 1 h.Fineness modulus of recycled fine aggregate is 2.98 and powder content is 8.0%,fluidity of CLSM is greater than 200 mm after 1.5 h.