PSI - Issue 78

Available online at www.sciencedirect.com

ScienceDirect

Procedia Structural Integrity 78 (2026) 1412–1419

© 2025 The Authors. Published by ELSEVIER B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0) Peer-review under responsibility of XX ANIDIS Conference organizers Keywords: losses; seismic risk; Bridges; displacement-based assessment; nonlinear time history analysis; capacity spectrum method Abstract Loss-based seismic design aims to meet user-selected performance targets in terms of earthquake-induced losses, such as fatalities, economic costs, or downtime. Implementing this approach in practice, without relying on cumbersome trial-and-error procedures, requires simplified loss assessment strategies. As a first step toward practical loss-based design for bridges, this study investigates the trade-off between simplicity (in terms of modelling effort and computational demand) and accuracy in the seismic loss estimation of reinforced concrete bridges. A parametric analysis is conducted on a set of 18 case-study RC bridges assumed to be in a high-seismicity region. For each bridge, a benchmark estimate of the expected annual loss is obtained using nonlinear time history analyses. These benchmark values are compared against estimates derived from a simplified alternative method deriving the force-displacement curve analytically with a displacement-based approach and deriving demand using the capacity spectrum method with as-recorded ground-motion spectra. Fragility analyses are conducted using both the cloud method, employing a power law functional form, and the multi-stripe method. The results highlight the cases in which the simplified analysis approach provides satisfying accuracy, while also outlining future research developments to improve the simplified procedures before being included into a non-iterative loss-based design methodology for bridges. XX ANIDIS Conference Accuracy of simplified loss assessment strategies for loss-based seismic design for reinforced concrete bridges Andrea Nettis a *, Roberto Gentile b , Domenico Raffaele a , Giuseppina Uva a a Department of Civil, Environmental, Land, Building Engineering and Chemistry Polytechnic University of Bari, Bari, Italy b Department of Risk and Disaster Reduction, University College London, London, United Kingdom

* Corresponding author. E-mail address: andrea.nettis@poliba.it

2452-3216 © 2025 The Authors. Published by ELSEVIER B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0) Peer-review under responsibility of XX ANIDIS Conference organizers 10.1016/j.prostr.2025.12.180