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Deterioration mechanisms, such as chloride-induced corrosion, affect bridges in aggressive environments, making them more vulnerable to extreme events like earthquakes. Although many studies have assessed the impact of chloride-induced corrosion on the seismic vulnerability of reinforced concrete (RC) highway bridges, several gaps still need to be addressed. Accordingly, this research primarily focuses on evaluating the seismic performance of RC highway bridges in aggressive environments susceptible to chloride-induced corrosion and earthquakes. To achieve this, a probabilistic framework is employed, which incorporates uncertainties associated with corrosion progression, seismic events, and the impact of different modeling approaches for boundary condition. The framework considers the time-dependent effects of corrosion on the physical and material properties of steel and concrete in bridge columns. Monte Carlo Simulations (MCS), probabilistic seismic hazard analysis (PSHA), and record selection strategies are utilized to address the uncertainties in corrosion and seismic demand. Nonlinear dynamic models and multiple stripe analysis (MSA) are employed to obtain fragility surfaces and curves for main bridge components and the entire system under different boundary conditions. The study focuses on a five-span highway bridge with simply-supported prestressed concrete I-girder and RC multi-column bents located in Chile. The results reveal that elastomeric bearings are the most vulnerable components, exhibiting varying vulnerability levels under different corrosion exposure and boundary conditions. Abutments, although the second most susceptible, are unaffected by corrosion uncertainty in terms of seismic fragility. Bridge columns are identified as the third most vulnerable components, with the probability of exceeding slight damage state consistently increasing with more prolonged corrosion exposure. It is noted that only flexure failure mode in column is analyzed and possible shifting to shear or flexure-shear modes is not accounted for. The findings of this study underscore the exceptional resilience of Chilean highway bridge columns to seismic demand and corrosion uncertainties, contrasting with the situation in US regions where columns are more vunerable. Additionally, the study indicates that Soil-Structure Interaction (SSI) tends to reduce bridge vulnerability under combined corrosion and earthquake effects. The insights obtained from this study and the proposed framework can inform the development of maintenance programs based on bridge performance expectations and enhance the seismic resilience of bridge systems worldwide. • Combined effects of chloride-induced corrosion and severe earthquakes are investigated. • Uncertainties in seismic demand and time-dependent corrosion process are accounted for. • State-of-the-art nonlinear numerical modeling of an actual bridge is used. • Effects of boundary conditions, fixed and with soil-structure-interaction, are analyzed. • Component and system fragility surfaces are developed. [ABSTRACT FROM AUTHOR]

• Performance of shear wall buildings was improved by increasing the lateral stiffness. • Larger stiffness reduced the probability of exceeding life safety limit state. • Larger stiffness reduced the probability of collapse for the same IM. • Larger stiffness increased the probability of collapse in 50 years. • Displacement ductility increased when the stiffness of the building decreased. This study assesses the effect of the stiffness on the seismic performance of residential shear wall buildings designed according to current Chilean regulations, including DS60 and DS61. Specifically, the paper focuses on the effect of stiffness on the building overstrength, displacement ductility, fragility for Life Safety (LS) and collapse limit states, as well as the probability of achieving these two limits states in 50 years. The seismic performance is assessed for a group of four 20-story residential shear wall buildings archetypes located in Santiago. Walls were modeled using the multiple vertical line element model (MVLEM) with inelastic hysteretic materials for the vertical elements, and a linear-elastic shear behavior. Pushover analyses were considered to estimate the buildings overstrength and displacement ductility, while incremental dynamic analyses were performed to estimate fragility curves. A probabilistic seismic hazard analysis, which considered the seismicity of Chile central zone, was performed to estimate the probability of achieving the two limits states in 50 years. The results show that an increase in the stiffness reduces the chance of exceeding the LS and collapse limit states for the same intensity level. Additionally, the probabilistic seismic hazard analysis shows that, when the stiffness increases, the probability of reaching the LS limit state in 50 years also decreases. Counterintuitively, the probability of collapse in 50 years increases as the stiffness increases, due to the considered seismic hazard and the design requirements. Since society is moving towards resilient structural designs that minimize damage, disruption and economic losses, it is concluded that the performance of reinforced concrete shear wall buildings is improved by increasing the stiffness. [ABSTRACT FROM AUTHOR]