Effect of chlorides on mechanical properties of FRP reinforced concrete columns

Chloride attack is one of the most important factors in marine environment which causes steel corrosion and structural deterioration, further leading to the shortened service life of concrete offshore structures. Fiber reinforced polymer (FRP) is expected to be a good candidate to replace steel rebar as internal reinforcement for offshore structure due to its excellent corrosion resistance, so as to improve the structural durability. In order to verify the effectiveness of FRP reinforced concrete under chloride attack, the effect of chlorides on the mechanical properties of FRP reinforced concrete column has been experimentally studied. The compressive test has been conducted to obtain the mechanical properties of concrete columns prepared with different salinity of mixing water. Only a 4% load capacity reduction of FRP reinforced concrete is observed when the mixing water changes from distilled water to seawater. Based on our experimental result, it can be concluded that the performance of FRP reinforced concrete prepared with seawater is reliable and satisfactory. A new concrete system adopting seawater and FRP reinforcement should be promoted for marine and offshore structures since such system can provide sufficient strength and durability, as well as a great convenience and economic benefit.