水泥石中固化态氯离子在硫酸盐腐蚀环境中变化特征

Change in Bound Chlorides of Cement Paste under the Attack of Sulfate Solution

采用长期浸泡方法,研究了内掺氯化钠水泥净浆经5%硫酸钠溶液和5%硫酸镁溶液腐蚀后,其内部固化态氯离子数量变化特征。结果表明:无论是硫酸钠溶液,还是硫酸镁溶液,均会导致固化态氯离子失稳,使其重新转变为游离态。这主要归结于两种溶液腐蚀对Friedel盐的分解。此外,硫酸镁溶液也会造成C-S-H凝胶所吸附氯离子的解附。但是,与硫酸镁溶液腐蚀相比,固化态氯离子稳定性更容易受硫酸钠溶液腐蚀的影响。

The change in the quantity of bound chloride ions in the cement pastes, which were made with NaCl solution, were investigated after them immersed in 5 % Na2 SO4 solution and 5 % MgSO4 solution for long time, respectively. The results indicated that the attack of Na2SO4 solution and MgSO4 solution can lead to the release of bound chlorides, which is mainly attributed to the dissolution of Friedel＇s salt under the attack of Na2SQ solution and MgSQ solution. In addition to, the bound chlorides absorbed by C-S- H gel also can be released due to the attack of MgSQ solution. However, the stability of bound chlorides is more susceptible to Na2SO4 solution attack compared with MgSQ solution attack.