## 1 Introduction  
Many scholars have studied the corrosion of reinforced concrete columns in chloride environments [1]. Earlier studies focused on the degradation of the mechanical properties of concrete columns with reinforcing steel bar corrosion. For example, [PERSON] et al. [2] found through a large number of tests on corroded columns that the impact of corrosion level on the ultimate strength of the compression column was significantly greater than that on the ultimate strength of the steel bar itself. The decreased effective section and strength of the steel bar as well as the damage to the concrete column section caused by corrosion are the key factors that reduce the bearing capacity of the corroded concrete column. [PERSON] [3, 4] and [PERSON] et al. [5] used the rapid corrosion method of applied extra electric currents to study the performance degradation of corroded reinforced concrete columns, such as stiffness, ductility, and bearing capacity. The results showed that the ductility and bearing capacity of the column decreased with increasing steel corrosion rate. [PERSON] [6] and [PERSON] et al. [7, 8] established a calculation model for the bearing capacity of eccentrically loaded columns by comprehensively considering the reduction of the section area and changes in mechanical properties caused by the corrosion of longitudinal bars, the geometric damage of the section caused by corrosion-induced cracks, and the reduction in bond strength after corrosion of longitudinal bars. In addition, [PERSON] [9], [PERSON] et al. [10; 11; 12], and many other scholars have studied the evolution of the mechanical performance of concrete columns in chloride environments with the degree of steel corrosion, reaching similar conclusions. However, these studies mainly focused on the changes in the mechanical properties of columns caused by longitudinal bar corrosion, without considering the effects of long-term loading and stirrup corrosion, which are somewhat different from the working conditions of the structure in service and thus cannot fully reflect the characteristics of the mechanical property degradation of concrete columns. Subsequently, some researchers have carried out studies investigating the force performance of corroded columns considering the loading factors. [PERSON] et al. [13] studied the effects of the corrosion of reinforcing steel bars and repeated axial loading on the seismic performance of a column pier. The results indicated that corrosion has significant influences on the yield strength and bearing capacity of a column. [PERSON] et al. [14] studied the characteristics of stress redistribution and performance degradation in the cross-section of axial compression columns after corrosion of the longitudinal main reinforcing steel bars on one side of the column under constant compressive stress. [PERSON] [15] carried out experimental research on load-bearing reinforced concrete-biased members under the alternating effects of mixed erosion and freeze-thaw, concluding that the continuous load proportion and environmental effects had accelerated effects on the reduction of bearing capacity, stiffness deterioration, and crack development in biased columns. [PERSON] et al. [16] performed bearing capacity tests and numerical simulations of PC bridge decks considering the corrosion of prestressed steel bars. In addition, the creep performance and bearing capacity calculation method of concrete columns under the action of load and environment have been reported in the literature [17; 18]. However, there is relatively little research and reported results on the changes in mechanical properties of corroded concrete columns under loading. Thus, further in-depth studies are required.