Can Marine Fouling Organisms Extend the Life of Concrete Structures?

摘要

This study was carried out to understand the effects of marine fouling organisms attached on the surface of marine concrete structures on long-term durability of the structures. Reinforced concrete specimens with and without artificially induced cracks were exposed to marine environments: tidal and submerged zones for two years at two ports in Japan and one experimental exposure facility. After two-year exposure, the spreading area and the weight of the organisms attached on the specimens were investigated, followed by chloride ion migration tests, oxygen diffusion tests, accelerated corrosion tests of rebars, and flexural loading tests. From the test results, it can be concluded that concrete surface is significantly improved by biologically made thin layers, which leads to prevention of seawater and oxygen ingress into concrete. Moreover, in this paper, the performance based design of marine concrete structures incorporating this biological effect is discussed.