SLAG-BASED HYDRAULIC BINDER, DRY MORTAR COMPOSITION COMPRISING SAME AND SYSTEM FOR ACTIVATING A SLAG-BASED BINDER

摘要

The aim of the invention is to provide a hydraulic binder based on ground granulated blast-furnace slag, devoid of Portland cement, which enables improved setting and hardening. For this purpose, the invention concerns a hydraulic binder comprising (in % by weight on a dry basis): A. at least 50 of at least one ground granulated blast-furnace slag; B. more than 5 of at least one calcium aluminate cement and/or of at least one calcium sulfoaluminate cement; C. more than 5 of at least one source of sulfate ions; D. between 1 and 5 of Ca(OH)2 and/or of Portland cement; E. between 0.01 and 1 of at least one alkali metal carbonate, preferably Li2CO3; F. and at least one alkalifying reagent consisting of at least one alkali metal carbonate and/or bicarbonate, different from E, (NaHCO3; Na2CO3; K2CO3 and mixtures thereof); with the conditions whereby: (i) the amount of C is sufficient that the sulfate ions of C can react with B and with A; (ii) the amount of F is sufficient that reaction thereof with component D in the presence of water brings the pH of the wet formulation obtained to a value of not less than 12, for a water-to-mortar mixing rate of between 10 and 35 % by weight.