Comprehensive Numerical System for Predicting Airborne Chloride Generation and Its Ingress in Concrete under Actual Environmental Conditions

摘要

The deterioration of concrete structures in airborne chloride environments is a common problem, as attested by the large number of concrete structures in coastal areas that are in need of repair due to corrosion of steel reinforcement. Thus, to prolong the service of concrete infrastructure in marine environments, deterioration from airborne chloride should be carefully considered. However, the amount of airborne chloride is influenced by numerous factors including wind direction, wind speed, wave height, obstacles, and distance from the seashore, and the concentration of airborne chloride varies by time and location. Besides actual exposure conditions, chloride ingress depends also on the environmental condition. In order to design the concrete structures, one must consider the amount of airborne chloride, concrete qualities, and the environmental conditions. Consequently, this research aims to develop a comprehensive system that can predict chloride ingress in concrete structures by considering airborne chloride intensity at the specific locations and times, based on determination of the amount of airborne chloride generated by breaking waves and transported by wind flow. The proposed methodology can determine the chloride penetration into concrete structures in various marine environments. The numerical framework has been verified through on-site measurements to confirm its validity.