Influence of chloride and corrosion attack on the seismic resistance of reinforced concrete walls under alternative climate scenarios

Reinforced concrete (RC) constructions located in aggressive environments are subjected to premature structural problems due to corrosion phenomena. The corrosion can affect the structural response to ultimate limit states caused by extreme loadings and earthquakes. The role of climate change in potentially aggravating corrosion and hence the seismic performance of structures deserves further investigation. In this paper, advanced numerical analyses of RC walls have been carried out to estimate two-dimensional (2D) chloride diffusion in concrete by multifactor diffusivity to account for humidity and temperature variations corresponding to alternative climate scenarios. 2D pitting corrosion is then calculated for each reinforcing steel bar. Subsequently, finite element model (FEM) nonlinear pushover analyses are carried out to investigate the force-displacement capacity of two RC wall case studies, a bridge pier and a peripheral building wall. The reduction of the strength and displacement capacities for these two wall structures is investigated for different degrees of corrosion. Results indicate that a reduction of the in-plane lateral strength of wall structures can be well estimated by coupling climate and corrosion. Walls in buildings were found to be more susceptible to reductions in strength, and sometimes displacement capacity, due to the type of reinforcement detailing typically employed, namely lumped reinforcement in the boundary ends of building walls.