A fiber‐based deterioration modeling framework for reinforced concrete structures subject to spatially non‐uniform corrosion patterns described by limited information

Reinforced concrete structures are often subject to significantly non-uniform corrosion patterns. In real situations, the information available about deterioration is incomplete and sometimes is reduced to qualitative judgments formulated by inspectors based on in-situ surveys. This work proposes a practice-oriented fiber-based modeling approach capable to model arbitrary spatial distributions of corrosion characterized by limited information. The approach is based on the partition of the structure into pieces, regions and zones and by the use of degradation laws for material parameters. Local and global deterioration scales are introduced to facilitate consistent specification of material parameters on the basis of qualitative judgments. The penetration of deterioration beyond the exposed surfaces is modeled by the concepts of exposition zone and deterioration attenuation laws. The approach has been implemented in a macroelement of arbitrarily corroded beam-column in OpenseesPy and validated by comparison with 16 experimental tests of columns with different section types, corrosion intensities, axial load and confinement levels. Results show that strength and ultimate drift can be predicted with remarkable accuracy.