An Earthquake Early Warning Decision Support System for Railway Bridge Infrastructure

Abstract

Earthquake early warning (EEW) systems deliver actionable information seconds before the arrival of damaging seismic waves from an oncoming earthquake at a target site. Such information can potentially contribute to mitigating the negative impacts of earthquakes on the operation of infrastructure assets. EEW-related decision making should use risk-based protocols, and the evaluation of the benefits of EEW systems should address all the possible rupture scenarios that may affect a specific location (or asset). This paper addresses these requirements for EEW on railway bridge structures. We first develop a risk-informed EEW decision support system (DSS) for these assets, combining information on site-specific seismic hazard, time-dependent EEW algorithm outputs, probabilistic seismic demand modeling, damage and derailment fragilities, and seismic loss models. These components are integrated into a multi-criteria decision-making framework that accounts for diverse stakeholder perspectives on risk. We then propose an approach for quantifying the loss-mitigation benefits (i.e., effectiveness) of the EEW-DSS across all possible relevant rupture scenarios affecting a railway bridge, based on value of information theory and accounting for dynamic accuracy/lead-time trade-offs related to EEW performance. A multi-span reinforced concrete railway bridge in Northeastern Spain is adopted as a testbed to showcase the proposed EEW-DSS and investigate its benefits. The findings from the analysis shed light on the importance of risk-based, uncertainty-informed, and stakeholder-oriented decision making to the loss-mitigation effectiveness of EEW for a railway bridge.