混合再生细骨料水泥砂浆性能试验研究

Experimental Study on the Properties of Mixed Recycled Fine Aggregate Mortar

研究了废弃混凝土和废弃黏土砖制成的混合再生细骨料的掺量(0、30%、60%、100%)和预湿时长(0、1/6 h、24 h)对砂浆流动性、抗压强度、抗折强度和干燥收缩性能的影响。结果表明:砂浆的初始流动度和流动度经时损失率随着再生细骨料掺量和预湿时长的增加而降低;随着再生细骨料掺量的增加,砂浆的抗压强度降低,抗折强度变化较小;砂浆的抗压、抗折强度随着再生细骨料预湿时长的增加呈增大趋势;由于再生细骨料的内养护作用,砂浆的干燥收缩量随再生细骨料掺量和预湿时长的增加呈减小趋势。

The effects of the content(0,30%,60%,100%)and pre-wetting time(0,1/6 h,24 h)of mixed recycled fine aggregate made from waste concrete and waste clay bricks on the fluidity,compressive strength,flexural strength and drying shrinkage properties of mortar were studied.The results show that the initial fluidity and fluidity loss rate of mortar decrease with the increase of recycled fine aggregate content and pre-wetting time.With the increase of recycled fine aggregate content,the compressive strength of mortar decreases,and the change of flexural strength is small.The compressive and flexural strengths of mortar tend to increase with the increase of pre-wetting time of recycled fine aggregate.Due to the internal curing effect of recycled fine aggregate,the drying shrinkage of mortar decreases with the increase of recycled fine aggregate content and pre-wetting time.