Preparation And Properties Of Cement-based Of Waterproof And Impervious Self-leveling Mortar

There are artificial spreading out, Calibrating, plastering and other processes in the traditional mortar construction, calendaring operations are also need performed three times before the final setting of mortar, This layered construction has many drawbacks, self-leveling mortar can solve these problems.Fly ash and slag powder can not either reduce production costs, but also improve the later strength of mortar, gypsum involve in the hydration and format ettringite, reducing the shrinkage of mortar, making mortar shrinkage maintained at less than 0.15% which is required by the industry standards, on the basis of ensuring compressive and flexural strength, experiment get better fluidity mineral admixtures content by using orthogonal analysis methods, adding sulphoaluminate cement and early strength agent increase the first day strength of mortar, polycarboxylate substituted naphthalene superplasticizer further improve the fluidity of the mortar, the function of water retention and thickening by cellulose ethers can solve the segregation and bleeding phenomenon triggered by polycarboxylate, incorporating defoamer reduce the porosity, making the mortar more dense and better waterproofing.The results showed that:① Mortar strength reduces after incorporation of fly ash and gypsum, gypsum can decreases mortar shrinkage, slag powder has higher activity, dosage of 10% has better strength than 5% and 7.5%, admixture with a reasonable degree can effectively improve the flow of mortar. ② Dosage of sulphoaluminate cement increases, the first day srength raise, when exceeding 11%, mortar viscosity increases, segregation, peeling from surface and efflorescence disappears, fluidity value reduces to less than 130mm.③ Polycarboxylate has high dispersing effect, can improve fluidity of mortar to more than 140 Millimeter, however, it will lead to segregation, cellulose ethers have effect of water retention and thickening, but it may delay the cement hydration, latex powder can increase flexibility of mortar and bond strength, the increasing dosage can derease strength.④ NC early strength agent can improve the first day flexural and compressive strengh to above 2 megapascals and 6 megapascals, but the improvement to the first day strengh is limited, with dosage increasing, slurry coagulation Accelerate, consistency increases, mobility decrease and segregation disappear. ⑤ After defoamers incorporating, mortar porosity reduces, liquidity value increases, mortar becomes more dense, compressive strength, flexural strength and impermeability pressure increases.Based on "JCT985-2005 ground with cement-based self-leveling mortar" and "JCT2090-2011, waterproof polymer slurry", we can know that, by univariate and orthogonal experimental analysis, the final optimal ratio of flexural and compressive strength, fluidity, dimensional changes and mortar specimens impermeability can meet the requirements.