Corrosion resistance of BFRP bars and rebars in concrete pore fluid simulating a marine environment

Abstract

Reinforced concrete structures in marine environments suffer from severe rebar corrosion. Basalt fiber reinforced polymer (BFRP) bars, which have better mechanical properties and corrosion resistance comparable to rebars, are a promising alternative. This study compares the durability of these two materials in concrete pore fluid simulating a marine environment. Through 0–100 days immersion experiments, it examines the mass and tensile property (tensile strength, elastic modulus, and ultimate strain) changes of the two types of bars, and uses the Arrhenius model, power function model, and exponential model to predict their long-term performance. Testing showed that after 100 days of immersion, BFRP bars had a mass loss rate of just 0.99%, compared to 3.83% for rebars. The minimum tensile strength retention rate of BFRP bars was 98.24%, versus 91.00% for rebars. The minimum elastic modulus retention rate of BFRP bars was 95.27%, while rebars only retained 92.25%. Thus, BFRP bars exhibited 7.24% and 3.02% higher tensile strength and elastic modulus retention rates, respectively, than rebars. Experimental results demonstrated that BFRP bars possess superior corrosion resistance to rebars in concrete pore fluids simulating a marine environment. Long-term predictions suggest BFRP bars last five times longer than rebars. This study shows that BFRP bars with excellent corrosion resistance and stable mechanical properties can replace rebars in marine concrete structures to effectively address corrosion issues.