材料期刊网

研究了硫酸盐、碳酸盐和硝酸盐与氯盐复合侵蚀下硅酸盐水泥固化氯离子性能，采用水溶法测定了水泥净浆中自由氯离子含量并计算得出其氯离子固化率，对试样进行了 XRD 物相分析以及其水溶液的pH值测定。结果表明，水泥浆体的氯离子固化率随水化龄期的增长而增加；随氯离子浓度增大，水泥浆体中 F 盐的生成量增加，其氯离子固化率先增大后减小。随硫酸盐和碳酸盐浓度增大，水泥浆体的氯离子固化率均降低，硫酸盐的降低程度稍微比碳酸盐大。硫酸盐和碳酸盐通过结合 AFm 分别生成钙矾石(3CaO?Al2 O3?3CaSO4?31H2O)和单碳硫铝酸钙(3CaO?Al2O3?CaCO3?12H2O)提高了水泥浆体的pH 值，减少了F盐的生成量。硝酸盐对水泥浆体的氯离子固化率和F盐的生成没有影响。

Chloride binding capacity of portland cement subj ected to complex corrosion of sulfate,carbonate,ni-trate with chloride salt was studied.The chloride ion binding rate of cement pastes were obtained through free chloride ions concentrations testing and analyzed by XRD and pH testing techniques.The results show that chloride ion binding rate of cement pastes increased with age increasing.With chloride ion concentration increas-ing,the amount of formation of Friedel’s salt increase,while the chloride ion binding rate increase at first then decreased.With sulfate and carbonate concentration increasing,chloride ion binding rate of cement pastes de-crease similarly which decrease slightly larger with sulfate than carbonate.Sulfate and carbonate can react with AFm to the generation of 3CaO?Al2O3?3CaSO4?31H2O and 3CaO?Al2O3?CaCO3?12H2O respectively, and it lead to the rise of the pH value and reduce the amount of formation of Friedel’s salt.Nitrate has no effect on chloride binding capacity of portland cement.