论文部分内容阅读
海砂和河砂的最大不同,就是海砂含有较高含量的氯离子。在拌制混凝土的过程中,这些砂中的氯离子和其他原材料中的氯离子都会进入混凝土体系当中。当混凝土体系中的总氯离子含量超过某个“阀值”的时候,混凝土中的钢筋表面钝化膜会遭受破坏,形成腐蚀电池,使金属铁不断变成铁锈。这个过程一方面不断减小钢筋的有效面积,降低钢筋的承载能力;另一方面铁锈密度远小于金属铁,生锈的过程就是体积数倍膨胀的
The biggest difference between sea sand and river sand is that sea sand contains a high content of chloride ions. In the process of mixing concrete, the chloride ions in these sands and the chloride ions in other raw materials enter into the concrete system. When the total chloride ion content in the concrete system exceeds a certain “threshold”, the passivation film on the surface of the reinforcing steel bar in concrete will be destroyed, forming a corrosive battery, which will turn the metal iron into rust continuously. On the one hand, this process continuously reduces the effective area of steel bars and reduces the carrying capacity of steel bars. On the other hand, the density of rust is much smaller than that of metal iron, and the rusting process is several times of volume expansion