憎水剂对超轻发泡混凝土性能的影响研究

Affecting Research of Water Repellent on Properties of Ultra-lightweight Foamed Concrete

以普通硅酸盐水泥与硫铝酸盐水泥为胶凝材料,采用物理发泡工艺制备了干密度小于300kg/m3的发泡混凝土,研究了三种憎水剂对发泡混凝土抗压强度、体积吸水率及孔结构的影响。研究表明:憎水剂掺量增加,试样7d及28d抗压强度先增加后降低,憎水剂硬脂酸钙相对于苯丙乳液及有机硅,对试样干密度及气孔结构影响最小,体积吸水率降低最为明显;当硬脂酸钙掺量为2.5%时,干密度为274.1kg/m3的试样28d抗压强度为0.65MPa,体积吸水率为8.6%。

For ordinary Portland cement and sulphoaluminate cement as cementitious materials, foamed concrete for dry density less than 300kg/m^3 is prepared by physical foaming process, the influence of three kinds of water repellents on compressive strength, volume water absorption and pore structure is investigated. The results indicate that, with the increasing dosage of water repellent, the compressive strength of samples with 7 days and 28 days is increased at first then decreased, compared with styrene-acrylate emulsion and organic silicon, the effect of calcium stearate on dry density and pore structure of samples is the least, and volume water absorption is decreased significantly. When the dosage of calcium stearate is 2.5%, the dry density of sample is 274.1kg/m^3, the compressive strength in 28 days achieves 0.65 MPa and the volume water absorption is 8.6%.