海洋潮汐区混凝土中氯离子传输过程的试验室模拟方法

An accelerated simulation experimental method of transport process of chloride in concrete exposed to splash from seawater

Cl-侵蚀是造成混凝土内钢筋锈蚀的主要原因,研究混凝土中氯离子侵蚀过程的试验室模拟方法是进行氯离子侵蚀过程研究的重要条件。本文通过实际海洋工程潮汐区和水下浸泡区氯离子传输过程的对比试验,揭示了干湿循环条件下氯离子在混凝土中的传输速率远大于饱水混凝土内外浓差引起的氯离子扩散速率,从而证明传统的浸泡试验方法无法用来预测干湿循环条件下氯离子传输速率,并在此基础上提出了实际海洋工程潮汐区氯离子传输过程的模拟试验方法,试验证明氯盐溶液喷淋—风干循环加速试验的氯离子传输机理和实际海洋环境潮汐区相同,是模拟海洋潮汐区的氯离子传输过程非常有效的方法。

The chloride contamination is one of the main causes that induce the corrosion of steel in concrete. The research on the accelerated simulation experimental method is very significant for studying transport process of chloride in concrete. A contrast experiment was carried out to study transport process of chloride in ocean environment in the paper. The test results indicate that the rate of chloride transport in concrete under wet and dry cycles （ exposed to splash from seawater） is faster than that immersed in seawater. It suggests that the mechanisms of chloride transport process are quite different in various environments. The transport mechanism of chloride in concrete exposed to splash from seawater in ocean enviromnents was analyzed. An accelerated experimental method of ＂spray-air-dry＂ wet and dry recycling was found. The further study shows that it is a very effective method, by which the transport mechanism of chloride is in correspondence with that exposed to splash from seawater.