Constitutive model of confined concrete with stirrups by acid rain erosion

In order to study the influence of stirrup corrosion level on the peak stress, peak strain, ultimate strain and shape of stress-strain curve of the confined concrete, 15 reinforced concrete prism specimens were subjected to acid rain erosion by artificial climate simulation technique followed by axial pressure tests. Based on Mander's model and the existing research results, the calculation formulas of the peak stress f'_cco, peak strain £_cco, ultimate strain ε_cco, ultimate strain ε_cu0 and shape factor r of the uncorroded specimens are determined. The factor calculation formulas for peak stress, peak strain, ultimate strain and shape factor of corroded specimens is developed by regression analysis of test data, respectively, and then the constitutive model of confined concrete by acid rain erosion is established. By comparing the simulation results with the experimental data, it can be found that all the peak stress, peak strain, ultimate strain and stress-strain curves shape of the specimens obtained by the proposed method are in good agreement with the experimental data. Thus the constitutive mode for confined concrete established in this paper can accurately reflect the mechanical performance of RC prism specimen by acid rain erosion, indicating its adaptiveness for estimating the residual bearing capacity and the seismic performance of RC structure under the acid rain environment.