# Damage Assessment of Shear Wall Structures in an Earthquake-Blast Disaster Chain
## 1 Introduction  
Reinforced-concrete shear wall structures possess excellent seismic performance and are commonly used in high-rise residential and commercial buildings [1]. However, earthquakes can trigger a chain of secondary and even tertiary disasters (fires [2], explosions [3], landslides [4], flooding [5], etc.). In some cases, the wall structures survive the earthquake intact but are then severely damaged by the following chain of disasters. Therefore, there has been an increased focus of research efforts on the risk assessment of shear wall structures that are potentially exposed to multiple hazards. The literature presents a variety of methods to analyze the performance and damage of shear wall structures when faced with multiple hazards, such as a combination of earthquakes, wind, rain, flooding, etc. [PERSON] et al. [6] described a multi-hazard-based framework to assess the potential of a high-risk building to be damaged when subjected to either separate or combined earthquake and wind hazards. The results demonstrated that the probability of damage induced by the dual-hazard earthquake is relatively high. [PERSON] et al. [7] studied the joint probabilistic model of earthquakes and rain for performing the failure risk assessment of structures. [PERSON] et al. [8] proposed a method for evaluating the failure probability of masonry structures under flood scouring and earthquakes. [PERSON] and [PERSON] [9] proposed the risk assessment for a variety of highway bridges subjected to earthquake and hurricane events. Earthquakes and explosions [10; 11] due to secondary causes (e.g., ignition of gas tanks) are among the most destructive hazards and should be accounted for in the design of buildings. Gas pipelines can rupture during earthquakes and cause gas to leak, which can lead to explosions when the gas concentration near a fire or spark exceeds a certain threshold. An earthquake-blast disaster chain is a low-probability, high-consequenceevent [12]. Although the probability of an earthquake-blast disaster chain is small, once it occurs, the structure will likely be subjected to loads that far exceed the pre-designed values. Such events can lead to great risks of structural failure, human injuries, and property damage. In recent years, many engineering structure failures during the earthquake-blast disaster chains have revealed deficiencies in conventional disaster-resistance design methods for engineering structures. For instance, in 2011, a hydrogen explosion occurred after the Great East Japan Earthquake, causing severe damage to the nearby power plant [3]. In 2017, infrastructural components caught fire and exploded during the Puebla-Morelos Earthquake in Mexico. The above-mentioned cases highlight the importance of considering the potential consequences of dual earthquake and explosion disasters. Additionally, such cases reveal that while current anti-seismic design codes work well, there is still uncertainty about whether structures can withstand the seismic-explosion disaster chain [13]. Therefore, the dynamic structural behavior, damage, failure mode, and assessment methods should be investigated to ensure structural safety during such situations. To bridge the gaps above, we investigated the response of a shear wall structure and derived a method to evaluate the damage that the shear wall structures may sustain in an earthquake-blast disaster chain. This paper is organized as follows. Section 2 proposes a theoretical framework for the damage evaluation of shear wall structures under an earthquake-blast disaster chain. Section 3 establishes a finite element model of the shear wall structure using the explicit dynamic FE analysis program LS-DYNA [14]. In Section 3, we describe the collection of recorded field data to facilitate the simulation of the simultaneous occurrences of earthquakes and blast loads. The blast-loading cases examine the effects of having explosions occurring separately at different locations.