Fragility Functions for Modern Reinforced-Concrete Beam-Column Joints

Fragility functions are developed to predict the method of repair required for modern reinforced-concrete beam-column building joints subjected to earthquake loading. These fragility functions, in combination with similar fragility functions developed previously for older joints, are used to compare damage progression in older versus modern joints. To develop fragility functions for modern joints, the results of previous experimental investigations are used to generate empirical relationships between damage and earthquake demand, damage states are linked deterministically with commonly employed methods of repair, and the empirical data are modeled using a standard probability distribution. The demand parameters, damage states, methods of repair, and probability distribution used in the current study are chosen to facilitate comparison with results from the previous study. The results of this study are a family of fragility functions that can be used to predict the method of repair required for a modern joint damaged due to earthquake loading and an improved understanding of the relative vulnerability of older versus modern components.