干湿时间比对海工混凝土结构氯盐扩散的影响研究

Effect of Wet and Dry Time Ratio on Chloride Diffusion in Marine Concrete Structures

为了探究海洋环境干湿交替区混凝土结构中氯离子扩散规律,将干湿时间比量化,对应连云港港口泊位现场环境与结构状况设计进行干湿交替区的混凝土构件在不同干湿时间比和不同压应力水平下的室内氯盐加速侵蚀试验,以混凝土内部扩散区的氯离子扩散系数和表面氯离子浓度作为侵蚀指标,将室内加速试验与现场试验的结果对比,分析干湿时间比和应力水平对氯离子扩散的影响。结果证明室内试验取得良好的加速侵蚀效果,试验结果表明对于干湿交替区的混凝土结构,干湿时间比对氯离子扩散的影响十分显著,不同的干湿时间比甚至将氯离子扩散系数提高2倍,其影响力远高于压应力水平。

In order to explore the law of chloride ion diffusion in concrete structure of dry-wet cycling zone in the marine environment, quantify wet-dry time ratio, in the field environment and structural condition of the port berth in Lianyungang, the accelerated corrosion tests of concrete components under different drywet time ratio and different compressive stress levels were carried out. Chloride ion diffusion coefficient and surface chloride ion concentration in concrete internal diffusion zone as erosion index, comparison of the results between indoor accelerated test and field test, the effect of dry-wet time ratio and stress level on chloride diffusion were analyzed. The results show that the indoor test has a good effect of accelerated erosion. The experimental results show that the influence of dry-wet time ratio on the diffusion of chloride ion is very prominent for the concrete structure in dry-wet cycling zone. Different dry-wet time ratios even increase the chloride ion diffusion coefficient by 2 times. The influence of dry-wet time ratio is much higher than that of compressive stress level.