Ordinary Portland cement,medium sulfate-resistant cement and slag with nano SiO2cement mortar samples were pre-pared with cement ratio of 0.36 and 0.50. Mortar samples were stored in 3% Na2SO4sulfate solution at(5±1)℃,and their strength developments were measured. Sulfate resistance of mortar samples was evaluated by considering the mortar strength and corrosion re-sistance. The results show that strength of 0.36 water-cement ratio specimen is higher than 0.50 water-cement ratio specimen under 5℃ environment,the sulfate resistance increases with the decrease of W/C ratio,and the addition of mineral admixture improves the sulfate resistance,the high the nano SiO2content is,the better the sulfate resistance effect. The mortar resistance to sulfate attack was 15% slag+3% nano SiO2>15% slag+1% nano SiO2>medium sulfate-resistant cement>ordinary Portland cement.%采用0.36、0.50这2种水胶比的普通硅酸盐水泥、中抗硫盐酸水泥以及加入矿粉与纳米SiO2的水泥砂浆试件,测试各试样在(5±1)℃的3%Na2SO4溶液中浸泡后的强度变化情况,综合考虑强度与抗蚀系数,对砂浆的抗硫酸盐侵蚀性能进行评价.结果表明:在5℃下,0.36水胶比试件的强度高于0.50水胶比试件,抗硫酸盐侵蚀性能随着水胶比的降低而提高;加入矿物掺合料提高了水泥砂浆的抗硫酸盐侵蚀性能,并且纳米SiO2的掺量越高效果越明显.砂浆抗硫酸盐侵蚀性能优劣顺序为:15%矿粉+3%纳米SiO215%矿粉+1%纳米SiO2中抗硫做盐水泥普通硅酸盐水泥.
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