Experimental Study On Properties Of Corrosion Resistant Steel Bars In Marine Environment

Part of the bridge section of the sea-crossing bridge is in a marine environment,as chloride ions in seawater and salt spray penetrate into the concrete to induce corrosion of steel bars,it is easy to cause structural damage.The damage degree is related to the amount of chloride ions that penetrate into the concrete and the penetration rate in the environment,The quality of concrete and the natural environmental conditions are closely related.Based on the development of corrosion-resistant steel bars in the marine environment,this article has designed a variety of chemical composition systems for alloy steels through laboratory research,and used small steel ingot tests and pilot tests to successfully develop concrete structures with high corrosion resistance under marine environmental conditions rebar HRB400 M.Through immersion corrosion and salt spray corrosion,the basic performance of the trial-produced HRB400 M steel bar,such as corrosion resistance,was studied,and the chemical composition was analyzed,its yield strength,elongation after fracture,elongation under maximum force,cold bending and reverse bending performance was tested.The product’s corrosion resistance,chemical composition,microstructure,mechanical properties and other properties can meet the requirements.Through the above research,trial-produced HRB400 M steel bars,compared with ordinary HRB400 steel bars,the corrosion potential and polarization resistance of the trial-produced HRB400 M steel bars are significantly improved,and the corrosion resistance is significantly improved.Through experimental testing,HRB400 M steel bars have excellent mechanical properties,the critical chloride ion concentration and amplitude of steel corrosion have been greatly increased,the service life of the concrete structure has been increased,and the thickness of the concrete protective layer has been reduced.According to the research,the design of key durability parameters is proposed and applied to the sea area section of a railway cross-sea bridge.The quality control measures for the durability of corrosion-resistant reinforced concrete are proposed to ensure the performance of the corrosion-resistant reinforced concrete of the cross-sea bridge that has been constructed so that the strength and thickness of the protective layer conform to the normal distribution and meet the design requirements.