Performance evaluation of marine circular reinforced concrete columns subjected to combined corrosion and compressive load

This paper presents an effective approach for quantitatively assessing the structural performance of the corroded reinforced concrete (RC) columns with a circular cross-section in aggressive marine environments. Firstly, the material damage and structural strength deterioration models are constructed by analyzing the degradation mechanisms of the materials due to rebar corrosion. The general method for calculating the load-bearing capacity of the circular RC columns at various corrosion levels with different loading conditions is proposed, based on the assumptions of the equivalent steel ring and the rectangular stress block of the concrete. In order to improve computational efficiency, a simplified method is then developed by introducing a linear relation to replace the complex expression of the load-bearing capacity coefficients of rebar in the general method. Finally, a numerical example is employed to investigate the effect of design parameters on the load-bearing capacity and performance deterioration rate of the corroded RC columns, and the effectiveness of the proposed simplified method is examined. The obtained results show that the corrosion level, loading condition and design parameters have a significant impact on the residual load-bearing capacity of the circular RC columns, and the simplified method with the introduced linear expression can be used for the preliminary assessment of the residual resistance of the corroded circular RC columns.