# Post-Earthquake Fire Resistance in Structures: A Review of Current Research and Future Directions
## 2 Background  
Existing research on post-earthquake fire (PEF) has explored a wide range of aspects, from community-level impacts to the behavior of specific structural components under the combined effects of seismic damage and fire [15]. Authors in [16; 17; 18; 19] highlight the complex interplay between these hazards and reveals critical vulnerabilities in the built environment. Early PEF research focused on community-level analysis, developing models to simulate fire ignition, spread, and suppression [20] within an urban context [21]. These models often incorporate physics-based fire safety principles and have the potential to integrate earthquake damage models for a more comprehensive evaluation [22; 23]. Some models account for various uncertainties, including earthquake-induced structural damage, to create realistic PEF scenarios [24; 25]. In contrast to building-level analysis, which emphasizes mechanical aspects, community-level analysis relies more heavily on principles of thermal and fluid dynamics. Building-level PEF analysis investigates the mechanical response of materials, components, connections, and entire structural systems. Studies on materials have examined the combined effects of earthquake damage and high temperatures on the properties of materials like steel [26; 27; 28]. Research on components has focused on elements such as concrete-filled steel tube (CFST) columns and load-bearing walls [29], assessing their fire resistance after cyclic loading [30; 31; 32]. Investigations into connections have explored the behavior of common configurations like moment-resisting beam-column connections under PEF conditions [33; 34; 35]. System-level studies have analyzed the response of entire structures [36; 37], including novel seismic-resilient systems [38; 39], to determine whether their PEF resistance benefits from reduced seismic damage. A critical area of research involves establishing the probabilistic relationship between earthquakes and subsequent fires [17]. Quantifying this risk is crucial for developing effective design and mitigation strategies [18]. This necessitates probabilistic models for PEF ignition, considering both external causes, such as damage to utility systems, and internal causes, like the overturning of flammable contents [4]. While hazard analysis often considers both internal and external ignition sources, it is often qualitative due to a lack of data for quantitative assessment [19]. Despite growing interest in performance-based assessment for PEF, significant knowledge gaps remain. Existing studies have explored PEF risk evaluation in urban areas [24], considering fire spread and evacuation, as well as the residual capacity of earthquake-damaged structures exposed to fire [22; 40; 41]. However, a comprehensive approach integrating probabilistic risk assessment, structural behavior analysis, and performance metrics is needed. Furthermore, the development of PEF fragility data [2], which relates structural demands to damage and loss, is crucial but currently limited. Specific research on structural elements and systems has focused on steel and reinforced concrete (RC) structures. Studies on steel structures have highlighted the importance of fireproofing materials and the detrimental effects of even minor losses in fire protection [3; 42; 43]. Research on RC structures has examined the impact of earthquakes on passive fire protection and the behavior of connections under PEF [44; 45]. Numerical and experimental methods have been employed to analyze the effects of PEF on various RC elements and full-scale frames [15]. Key findings from these investigations emphasize the importance of fire protection, the influence of drift ratio on fire resistance, and the dependence of failure mechanisms and PEF resistance on fire scenarios and gravity loads. Pre-existing earthquake damage significantly reduces fire resistance, and earthquake-induced deformations further increase vulnerability [46].