Theoretical model for electronic migration of chloride ions in water repellent concrete
Wang Tiao1 Dai Jianguo2 Yang Linhu3 Wu Peng 3
1. Department of Civil Engineering, The University of Tokyo
2. Department of Civil and Environmental Engineering, The Hong Kong Polytechnic University
3. Water Transport Planning and Design Institute, Ministry of Transportation
Abstract：Electrical migration test is a common method to evaluate concrete’s resistance to the chloride-ion penetration. However, it has been found that the existing migration models are not accurate enough to interpret the test results due to neglecting the effect of pore structure distribution in concrete on the migration process. Stanish et al. proposed a new model by considering the random characteristics of chloride migration velocity and found that the model prediction agreed well with the test results. Based on Stanish’s model, a simplified model is further developed herein by assuming that the chloride diffusion coefficient instead of the chloride migration velocity follows a logarithmic normal distribution. This assumption reflects more directly the random characteristics of concrete pore structures. It can simplify the solutions to a large extent with the same accuracy of prediction. This simplified model was verified to be also applicable to the migration tests of silane-based water repellent concrete. It was revealed that the silane-based water repellent only affected the surface chloride concentration during the migration tests. The measured electric flux can reflect the influence of silane-based water repellent on the penetration of chloride ions, however, the silver nitrate colorimetric method is inapplicable to evaluating the chloride resistance of concrete with silane-based water repellent.
王眺 戴建国 杨林虎 吴澎. 硅烷憎水处理混凝土的氯离子电场迁移模型研究[J]. 土木工程学报, 2017, 50(1): 20-27.
Wang Tiao Dai Jianguo Yang Linhu Wu Peng. Theoretical model for electronic migration of chloride ions in water repellent concrete. 土木工程学报, 2017, 50(1): 20-27.
