研究劈裂裂缝混凝土在海水全浸区和潮汐区作用下的氯盐腐蚀规律.试验结果表明:裂缝混凝土在海水全浸区和潮汐区氯盐腐蚀规律相似,氯离子含量由表及里随深度增加而下降,后在8～12 mm深度以内形成稳定段.但潮汐区混凝土的氯离子扩散系数比海水全浸区服役的裂缝混凝土的大.裂缝混凝土稳定段氯离子含量随裂缝宽度增加而呈指数函数增加,裂缝周边区域稳定段氯离子含量则随裂缝宽度增加而呈二次函数增加.相比海水全浸区腐蚀,潮汐区裂缝宽度对混凝土中氯离子传输影响更大.依据数据拟合回归,当潮汐区混凝土裂缝宽度为0.265和0.480 mm时,海水全浸区混凝土裂缝宽度为0.292和1.200 mm时,裂缝左右5rnm区域和30mm区域的氯离子扩散系数提高一个数量级.%The chloride salt corrosion of concretes with different size splitting cracks under marine environment was investigated. The splitting crack width of concrete is 0.03-0.2 nun. The cracked concrete and sound concrete were placed in marine tidal zone and submerged zone for 30 d, and the chloride ion content in crack zone and perimeter zone of concrete were quantitatively determined. The experimental results show that the chloride ion content of cracked concrete decreases with the increase of depth, and then gets to remain steady from 8 mm to 12 mm. The chloride ion distribution in cracked concrete under tidal zone and submerged zone is similar, but the chloride diffusion coefficient of cracked concrete in tidal zone is higher than that in submerged zone. The relationship between chloride ion content in the steady zone of concrete and crack width can be regressed as the exponential function and quadratic function for the crack zone and the perimeter zone, respectively. The influence of splitting crack on chloride transport in concrete is greater in the marine tidal zone than that in the submerged zone. Based on the regression of experimental dada, the splitting crack width of concrete is 0.26S and 0.480 mm in the tidal zone; the chloride diffusion coefficient of cracked concrete improves 10 times compared with sound concrete in crack zone and in the perimeter zone. And the same result appears when the splitting crack width of concrete is 0.292 and 1.200 mm for concrete under the marine submerged zone.
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