Mechanical performance and chloride ion penetration of polyolefin fiber reinforced concrete designed for shotcreting at marine environment

This work investigates the mechanical performance and chloride ion penetration of base concrete for shotcrete that was reinforced with non-corroding polyolefin fibers for marine structure application. Test parameters included polyolefin fiber and conventional steel fiber, use of ground granulated blast furnace slag (GGBFS), and two different methods to evaluate chloride ion penetration property (ASTM C 1202 and NT-BUILD 492). Test results show that concrete containing polyolefin fiber had lower compressive strength, flexural strength, and toughness than those with steel fiber, but still met mechanical property criteria of shotcrete. While charge passed value of the concrete with polyolefin fiber was lower than that with steel fiber, the chloride ion diffusion coefficient of the concrete with polyolefin fiber was slightly higher than that with steel fiber. Concrete replaced with 40% GGBFS by mass of cement leaded to better mechanical performance and chloride ion penetration resistance than that without GGBFS regardless of both ASTM C 1202 and NT-Build 492 methods. Based on the test results, the use of polyolefin fibers has benefit as reinforcement of shotcrete used for marine structure application.