Quantitative Method For Post-Windstorm Function of Community Shelters Considering The Impact of Urban Road Network

During strong windstorms in coastal cities, community shelters play a crucial role in reducing injures and ensuring the basic living needs of citizens. However, previous studies mainly focus on the function assessment of healthcare systems during earthquakes, few studies discuss the post-windstorm functionality of community shelters. Thus, this study proposes a quantitative method for the post-windstorm function of community shelters considering the impact of urban road networks. In which, the refugee traveling time (RTT) and refugee admitted ratio (RAR) are introduced to quantify the post-windstorm functionality of community shelters. Both the networks of urban roads and community shelters are established using graph theory, and the wind-induced fragilities of urban road facilities are included to quantify the physical damages during windstorms, including tree/pole blow-down, damages on building envelops, etc. Then, the population distribution and refugee generation models are also introduced. To determine accurate RTT and RAR, an efficient traffic flow allocation algorithm based on stochastic non-equilibrium assignment model are proposed to calculate the post-windstorm flows on urban roads. The proposed method can accurately and effectively quantify the post-windstorm functionality of community shelters, which can be applied on different cities and help improving urban resilience under wind hazards.