摘要
对各种海砂混凝土体系下的钢筋成型钝化膜,再通电加速腐蚀对钢筋进行破钝,并综合电化学方法和钢筋失重率对比研究了各体系下的混凝土中钢筋锈蚀规律。结果表明,淡水拌合淡化海砂混凝土体系中的钢筋耐锈蚀能力较好;随着Cl~-浓度的提高,钢筋的腐蚀行为越严重,但是存在临界Cl~-浓度。经过淡化处理的海砂使其氯离子含量降低至一定值内,是可以代替河砂使用。若直接用海砂来配制混凝土,则需要使混凝土内部生成或者本身带有较强的碱性物质,进而才能抑制高氯离子含量的混凝土体系中钢筋的锈蚀行为。
The passivation films of steel bars are formed under various concrete systems, and the steel bars are blunted by electric accelerated corrosion. Corrosion law of steel bars in various concrete systems is compared by electrochemical methods and weight loss rate of steel bars. The results show that, corrosion resistance of steel bars in washed sea sand concrete system with fresh water is better. With the increasing of Cl~- concentration, corrosion behavior of steel bar is more serious, but there is a critical Cl~- concentration. Sea sand resources can be used instead of river sand by washed treatment to reduce Cl~- content to a certain value. In order to prepare concrete with sea sand, it is necessary to make concrete internally generated or have strong alkaline substances to inhibit corrosion behavior of steel bar in concrete system with high Cl~- content.
引文
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