高钙粉煤灰对水泥浆体结构与性能的影响

Effects of High-calcium Fly Ash on Structures and Properties of Cement Paste

主要研究了高钙粉煤灰对水泥浆体流动性和抗压强度的影响,并从孔分布、孔总体积、总孔比表面积和平均孔半径等参数来分析高钙粉煤灰对浆体孔结构的影响.结果表明:在等水灰比下,高钙粉煤灰的掺入将改善浆体的流动性,提高总孔体积和降低抗压强度;然而,随着龄期增长,浆体平均孔半径显著降低,抗压强度降得更小;90 d龄期时,掺20%～40%质量分数高钙粉煤灰水泥浆体的抗压强度已基本与基准水泥浆体相同.

In this paper, effects of high-calcium fly ash (HCFA) on compressive strength and fluidity of paste were investigated, and parameters of pore structure such as pore size distribution, total pore volume, total pore specific surface area and average pore radius were analyzed. Results show that at the same mw/mc, the fluidity of paste is improved, the total pore volume increases and the compressive strength is reduced after HCFA is added. However, the average pore radius decreases remarkably with increase in the age, and therefore the reduction of compressive strength caused by HCFA becomes much less. The compressive strength of hardened pastes with 20%-40% HCFA at 90 d is equal to that of the hardened paste without HCFA.