STUDY ON EFFECT OF EARLY STRENGTH AGENTS ON STRENGTH AND STRUCTURE OF CEMENT MORTAR MIXED WITH SILICA FUME

The effect of different early strength agent on the strength and structure of the cement mortar mixed with silica fume were investigated.The results show that the early strength of the cement mortar mixed with silica fume is increased and reinforcing efficiency to compression strength of the cement mortar at 1 d is better than that at 3 d by adding different early strength agent to cement.A lot of crystals of ettringite produce rapidly to increase compactness of the cement mortar and pozzolanic reaction of silica fume is promoted in the meantime by adding proper content of sodium sulfate to cement so that the early strength of the cement mortar mixed with silica fume is increased obviously.But the early strength agents have little influence on the late age strength of the cement mortar mixed with silica fume.The reinforcing efficiency order relation of three kind early strength agents from great to small on the the early strength of the cement mortar mixed with silica fume is sodium sulfate,calcium chloride and triethanolamine.The reinforcing efficiency of sodium sulfate with the content of 3% is the best.