研究了经20℃标准养护和60℃蒸汽养护后粉煤灰、硅灰对水泥浆体抗压强度和干缩的影响,结果表明:标养下,粉煤灰的掺入降低了水泥浆体的强度,当粉煤灰掺量小于40％时,水泥浆体的干缩随着掺量的增加而增大,硅灰的掺入可以提高水泥浆体的强度,掺量小于15％时,各龄期的干缩随着硅灰掺量的增加而增加.蒸养提高了浆体的3d强度却降低了180 d强度.在蒸养下,当粉煤灰的掺量小于40％时,可以提高水泥浆体早期强度.复掺粉煤灰和硅灰可以减小水泥浆体的干缩.%The compressive strength and drying shrinkage of Portland cement pastes with different dosages of fly ash and silica fume cured at 20 ℃ and 60 ℃ before drying was investigated.The drying shrinkage and the compressive strength of hardened pastes were measured by a length comparator and strength measurement.Results show that after curing at 20 ℃,the corporation of fly ash reduces the compressive strength of cement paste.The drying shrinkage of cement paste increases with the addition increasing when the addition of fly ash is less than 40％.The incorporation of silica fume can improve the compressive strength.The drying shrinkage of cement paste with silica fume also increases with the increase of the addition when the dosage of silica fume is less than 15％.Steam curing can improve 3-day compressive strength of paste,but reduce 180 d strength.Mter being cured at 60 ℃,the addition of fly ash can improve the early-age compressive strength of cement paste when the dosage of fly ash is less than 40％.The drying shrinkage of cement paste decreases when fly ash and silica fume is blended after being cured at 60 ℃.
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