碳化与氯盐复合作用下硫氧镁胶凝材料的护筋性

为探究硫氧镁(MOS)胶凝材料的护筋性,研究了自然养护、碳化、氯盐以及碳化和氯盐复合作用下MOS胶凝材料的电化学阻抗、钝化和脱钝钢筋的极化曲线以及锈蚀面积率.结果 表明:碳化、氯盐单独作用下,MOS胶凝材料中钢筋的阻抗均低于自然养护下的相应阻抗,且随着龄期的延长,钝化钢筋的阻抗均呈现先减小后增大的趋势,脱钝钢筋的阻抗则持续减小;碳化和氯盐复合作用下MOS胶凝材料中钢筋的锈蚀程度明显增加,碳化和氯盐复合作用对MOS胶凝材料内部钢筋锈蚀程度具有叠加效应;各种腐蚀环境中脱钝钢筋的锈蚀程度均高于钝化钢筋.

Corrosion Resistance of Steel Bars of Magnesium Oxy-sulfate Cementitious Material under the Combined Action of Carbonation and Chloride Salt

In order to study the corrosion resistance of MOS cemented materials, the electrochemical impedance, polarization curve and corrosion area ratio of steel bars under natural curing, single and combined action of carbonation and chloride salt were investigated by electrochemical analysis method. The results show that the impedance of passive and de-passive steel bars under single carbonation and chloride salt condition is lower than that in natural curing, and the corrosion rate of passive and de-passive steel bars increases first and then decreases with the increased age of carbonation and chloride salt. Under the combined action of carbonation and chloride salt, the electrochemical impedance of passive and de-passive steel bars in MOS cemented materials is further reduced, and the corresponding corrosion degree of the passive steel bars is twice as much as that under the alone carbonization condition, and 1.2 times more than that under single chloride condition, which reflects the superposition effect of combined action of carbonization and chloride on the corrosion rate of steel bars in MOS cemented materials.