碳化对海砂混凝土中氯离子扩散的影响

Effects of Carbonation on Chloride Penetration in Sea Sand Concrete

选取海阳海砂、淡化海阳海砂和河砂三种细骨料,分别制备强度等级为C30和C50的混凝土,进行加速碳化与氯离子侵蚀复合试验的研究,测出混凝土试块不同深度的水溶性自由氯离子含量.结果表明:海砂混凝土、淡化海砂混凝土在碳化与氯离子侵蚀复合作用下的破坏规律与河砂混凝土基本一致.碳化时间对各种混凝土中氯离子的扩散影响都很大.混凝土强度等级,海砂中固有的氯离子等因素也影响混凝土各深度的水溶性自由氯离子含量.

Three kinds of sand are selected to make concrete specimens with strength classes of C30 and C50,which are natural sea sand,washed sea sand and river sand from Haiyang City.After the experiment of accelerated carbonation and chloride penetration,the free chloride content of concrete at different depth is measured.Conclusion can be made that the specimens made of three kinds of sand degrade have almost the same rule under the invading of both accelerated carbonation and chloride penetration.The time of carbonation has great influence on chloride penetration in all kinds of concrete specimens.The concrete strength classes and intrinsic chloride content of sea sand influence the chloride content of concrete at different depth as well.