早强剂对掺硅灰的水泥砂浆强度与结构影响的研究

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

探讨了不同早强剂对掺硅灰的水泥砂浆强度及微观结构的影响.结果表明:掺入不同的早强剂均可提高掺硅灰的水泥砂浆早期强度,且对其1 d抗压强度的增强效果优于3 d.其中掺入适量的硫酸钠可迅速生成大量的钙矾石晶体,提高水泥砂浆的密实度,同时促进了硅灰的火山灰反应,明显提高了掺硅灰的水泥砂浆的早期强度,但早强剂对掺硅灰的水泥砂浆后期强度影响不大.3种早强剂对掺硅灰的水泥砂浆早期强度增强作用从大到小的顺序依次为硫酸钠、氯化钙、三乙醇胺,其中硫酸钠掺量为3%时增强作用最佳.

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.