| 摘要 |
PROBLEM TO BE SOLVED: To considerably increase the rate of water reduction of a high performance water-reducing agent and to ensure high strength by incorporating the water-reducing agent, carbonate or hydrogencarbonate of sodium or potassium, a tripolyphosphate or ammonium hydrogencarbonate and a lignin sulfonate. SOLUTION: The cement compsn. contains 0.3-2.5 pts.wt. (expressed in terms of solid) high performance water-reducing agent based on 100 pts.wt. cement, 0.05-0.65 pt.wt. one or more selected from carbonate or hydrogencarbonate of sodium or potassium, a tripolyphosphate and ammonium hydrogencarbonate and 0.05-0.5 pt.wt. (expressed in terms of solid) lignin sulfonate or further contains one or more selected from 1-15 pts.wt. (expressed in terms of CaSO4 ) gypsum, 1-12 pts.wt. activated silica and 2-15 pts.wt. pozzolan. The water- reducing agent is, e.g. based on a polyalkylallylsulfonate, an arom. aminosulfonesulfonate or a melamine-formaldehyde resin sulfonate. |
