镍铁渣粉对混凝土抗硫酸盐侵蚀性能的影响

Influence of ferro-nickel slag powder on the sulfate attack resistance of concrete

为研究镍铁渣粉对混凝土抗硫酸盐侵蚀性能的影响规律和机理,该文测定了混凝土在硫酸盐侵蚀试验开始前的连通孔隙率和电通量,开展了硫酸盐溶液干湿循环和高温浸泡2种侵蚀性试验。试验结果表明:2种硫酸盐侵蚀性试验方法的结果是一致的;随着电炉镍铁渣粉掺量的增加,混凝土的连通孔隙率增大,抗硫酸盐侵蚀性能降低;在高炉镍铁渣粉掺量30%的范围内,随着掺量的增加,混凝土的连通孔隙率减小,氯离子渗透性等级降低,抗硫酸盐侵蚀性能提高;高炉镍铁渣粉对混凝土抗硫酸盐性能的增强作用效果不及高炉矿渣粉,尤其在掺量较大的情况下。

The influence of ferro-nickel slag powder on the sulfate attack resistance of concrete and the corresponding mechanism were investigated by measuring the porosity and charge passed through the concrete and the compressive strength loss below and after the concrete experienced a dry-wet cycle in a sodium sulfate solution and immersion in a high temperature sodium sulfate solution. The results show that the effect of the two kinds of sulfate attacks were the same. The connected porosity of the concrete increases and its sulfate attack resistance decreases with increasing electric furnace ferro-nickel slag powder content. The connected porosity of the concrete decreases, the chloride ion penetrability decreases and its sulfate attack resistance increases with increasing blast furnace ferro-nickel slag powder with mass fractions less 30%. The sulfate attack resistance of concrete is enhanced less by adding blast furnace ferro-nickel slag powder than by adding blast furnace slag power especially at high powder mass fractions.