石灰石矿渣水泥抗硫酸盐性能的研究

Research on Sulfate Resistance of the Limestone-Slag Cement Mortars

对于长期浸泡在3%(质量分数,下同)硫酸钠溶液中的石灰石矿渣水泥抗硫酸盐腐蚀性能进行了初步研究,并与普通硅酸盐水泥砂浆进行了比较.结果表明:石灰石矿渣水泥显示出良好的长期强度发展和优异的抗硫酸盐性能.在硫酸钠溶液中浸泡360,730d后,石灰石粉掺量为60%,50%,40%的石灰石矿渣水泥砂浆试样的抗蚀系数(SRC)分别高达1.10,1.08,1.18和1.06,1.10,1.11,高于同期的普通硅酸盐水泥砂浆试样42.9%和55.9%以上;以标准养护28d试样的抗压强度为基准,石灰石粉掺量为60%,50%,40%的石灰石矿渣水泥抗压强度增加率分别达到36.9%,43.7%,48.3%和40.2%,55.3%,57.7%,普通硅酸盐水泥的抗压强度下降率则为5.2%和30.3%.

To compare with ordinary Portland cement mortars, the resistance to the sulfate attack of the limestone-slag cement with different content of limestone powder which was immersed in 3% （by mass） Na2SO4 solution for a long period was investigated. The results show that the limestone-slag cement has better long-term strength and sulfate resistance; after being immersed in Na2SO4 solution for 360 d and 730 d, the sulfate resistance coefficient（SRC） of the limestone-slag cement mortars containing 60%, 50%, 40% of limestone powder in test specimens reach 1.10,1.08,1.18 for 360 d and 1.06,1.10,1.11 for 730 d respectively. That is higher than the ordinary Portland cement mortars up to 42.9% and 55.9%. To compare the compressive strength of the limestone-slag cement with that of ordinary Portland cement at the standard curing 28 d, the compressive strength of the limestone-slag cement can be increased by 36.9%, 43.7%,48.3% and 40.2%,55.3%,57.7%, but the compressive strength of ordinary Portland cement can be decreased by 5.2% and 30.3%.