消泡剂对新拌砂浆性能的影响研究

Influence Research of Defoamer on Properties of Fresh Mortar

在聚羧酸系高效减水剂中复配消泡剂,探讨了消泡剂掺量对砂浆性能的影响。结果表明:当基准砂浆加入消泡剂时,基准砂浆的含气量大幅度降低;砂浆处于高流动度状态时,增加消泡剂掺量,砂浆的流动度逐渐增大、含气量逐渐降低且最终趋于稳定、黏度逐渐降低、屈服应力呈现先减后增的趋势,当消泡剂掺量为0.5g时,屈服应力达到最小;固定配比时,增加水胶比,砂浆含气量呈现升高的趋势。

Effects of defoamer dosage on properties of mortars were investigated by adding defoamers into the polycar- boxylate superplasticizer. The experimental results show that： when adding defoamer in the reference mortar, the air con- tent of the mortar could decrease sharply; when the mortar is in a high state of fluidity, with the increase of defoamer dosage, the fluidity of mortar increases gradually, the air content of mortar reduces gradually and eventually tends to stabi- lize, the viscosity of mortars could reduce gradually, and the yield stress of mortar presents a trend of decreasing at first and then raising, when the defoamer dosage is 0.5g, the yield stress of mortar reaches a minimum value; when the W/B in- creases, the air content of mortar tends to increase at a fixed mix proportion.