Extension of displacement‐based simplified procedures to the seismic loss assessment of multi‐span RC bridges

Abstract

AbstractSimplified seismic assessment procedures relying on displacement‐based formulations have recently been implemented for the evaluation of the seismic performance in buildings and bridges. For bridges, displacement‐based assessment procedures have been formulated to predict the displacement response at several performance levels defined based on the expected damage on the structural elements. These displacement profiles have been subsequently used to estimate the performance level achieved under a given seismic hazard intensity and to develop damage fragility curves. For buildings, these concepts have been extended to compute economic losses in agreement with current performance‐based earthquake engineering procedures. In this study, existing displacement‐based formulations for the approximate seismic assessment of single‐column multi‐span continuous RC bridges, with non‐sacrificial shear keys for the pier‐to‐deck connections, are extended for the computation of expected annual losses under transverse direction excitation. Additionally, an iterative response spectrum analysis procedure, which directly considers higher mode effects, is proposed for computing the displacement response, and these results are also used to estimate direct expected annual losses. Results show that both procedures tend to compute higher losses when compared with those obtained with a fully probabilistic loss assessment framework, using demand estimations computed with nonlinear response history analysis. Results also show that the simplified loss assessment procedure is highly sensitive to the definition of the collapse fragility curve.