BINARY SILICOFLUORIDE LIQUID ADDITIVE COMPOSITION FOR IMPROVEMENT OF WATERPROOFNESS AND STRENGTH OF CONCRETE AND PREPARATION THEREOF

摘要

PURPOSE: A binary silicofluoride solution, as an additive, comprising zinc silicofluoride and magnesium silicofluoride is provided to improve waterproofness and strength of concrete. CONSTITUTION: The liquid additive, silicofluoride solution(5-30%(w/w)), comprises 50-90wt.% of zinc silicofluoride(Zn(SiF6)) as a main material and 10-50wt.% of magnesium silicofluoride(Mg(SiF6)) as an auxiliary material, where the Zn-source is one compound selected from ZnO, ZnCO3, ZnSO4 and Zn(OH)2, and Mg-source is one compound selected from MgCO3, MgSO4 and Mg(OH)2. The binary silicofluoride solution is prepared by adding MgCO3 to H2SiF6(25%), adding ZnO, stirring for 1hr. and diluting with water to get 5-30%(w/w) of concentration. The prepared liquid additive of 1-3wt.%(based on the cement) is added to cement in mixing.