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• Framework is established for performance-based assessment in post-earthquake fire engineering. • Methodology is illustrated by a case study on the performance evaluation of a steel system. • Dual-cause PEF ignition model is built for the probabilistic causation in earthquake-fire sequence. • Structural demands to both intensities are obtained by nonlinear analyses and mathematical extension. • Damage and loss assessment is conducted with fragility development and indicator quantification. Post-earthquake fire (PEF) is a threatening hazard triggered immediately after an earthquake, resulting in extensive destruction and casualties. It is important to evaluate structural performance in this typical cascading hazard to develop mitigation strategies and improve multi-hazard resilience. However, existing research mainly focuses on the structural response in PEF scenarios, while there is still a lack of knowledge on other critical parts of performance evaluation. In contrast, there has been a well-established methodology for performance-based assessment in earthquake engineering (PBEE), which can be regarded as the basis for extension to PEF scenarios. Based on that, a comprehensive framework has been proposed in this study for performance-based assessment in post-earthquake fire engineering (PB-PEF-E). To demonstrate the feasibility of the proposed methodology, an illustrative example of a realistic multi-storey steel frame is presented with specific details. The overall procedure considering the hazard, structure, damage, and loss domains is utilised for step-by-step PEF performance evaluation. Firstly, a dual-cause PEF ignition model is used to capture the probabilistic causation among the earthquake-fire sequence, considering ignition related to utility system damage and ignitable contents overturning. Then, structural demands with respect to both earthquake and fire intensities are obtained by a series of nonlinear analyses via numerical modelling, and uncertainties that significantly influence the responses are included. Finally, the structural capacity in different performance levels is estimated with PEF fragility development, and the consequences are measured using quantitative indicators for decision-making. The proposed methodology provides important benefits in evaluating the performance of alternative solutions thus facilitating robust decision-making in PEF scenarios, and it can be further extended to performance-based assessment in other multi-hazard scenarios with cascading effects. [ABSTRACT FROM AUTHOR]

• System-level numerical analysis is conducted on a self-centring frame under post-earthquake fire. • Combined effects of pre-damage and temperature are integrated into the proposed material model. • Various earthquake-fire combinations on single and multiple storeys compose the considered scenarios. • Quantitative assessment is provided by comparing structural responses with a conventional frame. • Target self-centring system exhibits favourable performance throughout the earthquake-fire sequence. Post-earthquake fire is a multi-hazard combination with cascading effects, of which catastrophic consequences are not only caused by the earthquake but exacerbated by the triggered fire. Only a few studies focused on the system-level structural analysis in earthquake-fire sequence, mostly on the conventional moment-resisting frame. Despite the self-centring system being a novel structure with excellent seismic performance, its post-earthquake fire response is still unclear due to limited research. Accordingly, this study aims to investigate the system-level behaviour of a self-centring system under post-earthquake fire. A numerical model of the six-storey prototype frame is established, and a two-stage bilinear material model is proposed to reflect the combined effects of pre-induced damage and temperature on material properties. A total of 11 ground motions (DBE and MCE levels) followed by 3 fires on different storeys compose the post-earthquake fire scenarios. A welded moment-resisting frame with reduced beam sections (WR-MRF) is selected for comparison, with the DBE response designed the same as the self-centring frame (SC-MRF). Results show that the SC-MRF exhibits smaller responses to the preceding earthquake and subsequent fire than the WR-MRF. Post-earthquake fire mainly affects two inter-storey drift ratios in each scenario, while it has a negligible effect on others which remain unchanged from the residual status after the earthquake. An obvious increase in structural responses can be found from fire-only (FO) to post-MCE fire (P-MCE-F) scenarios, and deformation is slightly larger in multi-floor fires than in single-floor ones. The findings unveil the post-earthquake fire responses of a seismic-resilient system with self-centring mechanism and provide a comparative assessment against the conventional structure. The methodology, including the proposed material model, can be further extended for analysis on other systems to understand and enhance the comprehensive performance in earthquake-fire sequence. [ABSTRACT FROM AUTHOR]