Experimental study on the degradation of mechanical properties of H-shaped steel columns in the chloride salt environment

Steel structures often experience significant durability degradation over time due to extreme environments. To better understand the impact of chloride environments on the mechanical properties of steel compression members, accelerated corrosion tests were conducted on H-shaped steel short columns with applied current. Monotonic tensile tests were also performed on steel specimens, and axial compression tests were carried out on H-shaped steel short columns with varying degrees of corrosion. The results revealed that the corrosion rate increased with higher current intensity and longer electrification duration while changing with different chloride ion concentrations. As the corrosion rate increased, the steel material exhibited a linear decrease in yield strength, ultimate strength, and elastic modulus. Consequently, the mechanical properties of the H-shaped steel columns, such as stiffness, ductility coefficient, and load-bearing capacity, were adversely affected. Based on these findings, a predictive formula was proposed to estimate the ultimate load-bearing capacity of H-shaped steel columns with different degrees of corrosion in chloride salt environments. The experimental results were further validated through numerical simulations, and parameter analysis indicated a negative correlation between flange width-to-thickness ratio, web height-to-thickness ratio, and ultimate load-bearing capacity of H-shaped steel columns. Finally, a random corrosion pit generation algorithm is proposed, effectively simulating the actual corrosion pit distribution and calculating the ultimate bearing capacity of columns.