Risk Assessment of Human and Vehicle Stability in Extreme Weather Events in Coastal Cities

As urbanization and climate change accelerate, extreme flood events in urban areas have significantly increased, posing a major threat to human and property safety. As an efficient research tool, numerical simulation technology has shown significant application value in mitigating the impacts of urban flood disasters. This study integrates multiple data sources, including Digital Elevation Models (DEM), topographical features, underground sewer systems, rainfall intensity, water level dynamics, and pump station operations, to construct an urban flood inundation simulation. Additionally, using the incipient velocity formula, the dynamic flood risk levels for humans and vehicles were quantitatively analyzed. The main results include: 1. The numerical model accurately simulated the hydraulic characteristics of flood events. The Coefficient of Determination (R2) was 0.9037, indicating high model reliability and providing a solid foundation for subsequent risk assessments. 2. During peak rainfall periods, the risk level for humans and vehicles escalates significantly. After the peak, the slight risk for humans decreases, while the magnitude of extreme risks in later stages becomes more severe with larger rainfall return periods. Conversely, the flood risk for vehicles steadily increases, surpassing that of humans overall. 3. In the later stages of rainfall events, both humans and vehicles encounter extensive areas where water depths exceed danger thresholds, transforming them into extreme risk areas. The results obtained in this research contribute to enhancing public awareness of urban flood risks and revealing the spatiotemporal evolution of these risks. They also provide important theoretical support and practical guidance for enhancing urban resilience and promoting sustainable development.