Significance of Modeling Deterioration in Structural Components for Predicting the Collapse Potential of Structures Under Earthquake Excitations
The paper presents a summary of the state of knowledge in structural component and system modeling for predicting the collapse potential of buildings structural systems. In this context, collapse implies dynamic instability in a sidesway mode, usually triggered by large story drifts that are amplified by structure P-Δ effects and deterioration in strength and stiffness of the components of the system. The collapse capacity of a building is defined as the maximum ground motion intensity (often represented by the spectral acceleration at the first mode period) at which the structural system still maintains dynamic stability. A collapse fragility curve that incorporates aleatory uncertainty due to record-to-record (RTR) variability is obtained by ordering the collapse capacities for a representative set of ground motions. Realistic modeling of deterioration is found to be the most essential aspect of collapse prediction through nonlinear dynamic analysis.