SUPER SET RETARDANT AND CONTROL METHOD OF MASS CONCRETE USING SUPER SET RETARDANT

摘要

PURPOSE: A super set retardant comprising sugar solution, thickener and air entraining agent is provided to delay setting and hardening time of concrete or cement mortar, enabling transportation and storage for a long time. Also, the retardant controls heat of hydration in casting, resulting in reduction of cracking. CONSTITUTION: The super set retardant is obtained by mixing sugar solution, thickener solution and air entraining(AE) agent in a weight ratio of 1 : 0.1-1.5 : 0.001-0.01, wherein the sugar solution is prepared by dissolving sugar and water in a weight ratio of 1 : 1 and the thickener solution is prepared by diluting thickener powder, polyethylene oxide(PEO), into water. Also, the heat of hydration of mass concrete is controlled by the following steps of: dividing a section of mass concrete uniformly; adding a large quantity of super set retardant to the lower part of concrete and a small quantity of super set retardant to the upper part of concrete, wherein the amount of retardant is in the range of 0.01-0.2%; casting conventional concrete on the upper part.