ABSTRACT
Hospital emergency departments are highly important systems and treat injured people during earthquakes. It is essential that their functionality is maintained during or recovered immediately after a disastrous earthquake; this is referred to as seismic resilience. A systematic analysis of the involved components and their influence on the functionality are required to quantify the functionality and seismic resilience. A number of studies have analyzed emergency departments under normal operating conditions using various system analysis methods. However, there are few studies on the post-earthquake performance of such systems. To this end, we propose an evaluation framework based on the state tree method to quantify the component’s influences on the functionality and seismic resilience from an engineering perspective. A typical emergency department is analyzed, and the state tree model is developed. The component contribution to the functionality is explicitly expressed using the fault tree method, and the failure transfer mechanism is determined by success paths. The functionality is thus defined as the ratio of successful paths to total possible paths. The system fragility is then calculated based on the full probability theory, and the results are used to validate the simulation method. The critical components that significantly affect the functionality and the recovery can be identified while considering a practical repair process. Finally, the resilience curve of the emergency department is developed based on the fragility of the components. The effectiveness of the proposed method for the functionality quantification and the resilience evaluation is fully demonstrated.
