可再分散乳胶粉对石膏基自流平砂浆性能的影响

Effect of Redispersible Latex Powder on Properties of Gypsum-based Self-leveling Mortar

以脱硫石膏为主要胶凝材料,掺入普通硅酸盐水泥和外加剂,制备了石膏基自流平砂浆,研究了不同掺量(0、1%、2%、3%、4%)的可再分散乳胶粉对石膏基自流平砂浆工作性、力学性能和耐水性能的影响,并采用XRD和SEM进行了微观分析。结果表明:掺入适量的可再分散乳胶粉能够提高石膏基自流平砂浆的流动度;可再分散乳胶粉的掺入降低了石膏基自流平砂浆的抗压强度、抗折强度和耐水性能,同时降低了压折比,从而提高了石膏基自流平砂浆的韧性和抗裂性,降低了脆性;石膏基自流平砂浆的水化产物主要为二水石膏、钙矾石等。

Using desulfurization gypsum as the main cementitious material,mixed with ordinary silicate cement and admixtures,the gypsum-based self-leveling mortar was prepared.The effects of different contents(0,1%,2%,3%,4%)of redispersible latex powder on the workability,mechanical properties and water resistance of gypsum-based self-leveling mortar were studied,and the microscopic analysis was carried out by XRD and SEM.The results show that adding appropriate content of redispersible latex powder can improve the fluidity of gypsum-based self-leveling mortar.The addition of redispersible latex powder reduces the compressive strength,flexural strength and water resistance of gypsum-based self-leveling mortar,and reduces the compression flexural ratio,thereby improving the toughness and crack resistance of gypsum-based self-leveling mortar and reducing brittleness.The hydration products of gypsum-based self-leveling mortar are gypsum dihydrate,ettringite and so on.