An Integrated Model for Dam Evacuation Under Explosion-Induced Damage: Coupling Physical Damage and Crowd Behavior

This study develops an integrated computational framework to assess the passage efficiency of a dam crest serving as a critical inter-regional corridor following a severe explosion event. The framework combines a physics-based damage model with an agent-based cellular automata (CA) approach that incorporates pedestrian behavioral heterogeneity. The damage model conceptualizes three concentric zones: a complete fragmentation zone (0–1.5 m) with total material disintegration, a primary damage zone (1.5–5 m) following an exponential decay in structural integrity, and a secondary damage zone (5–20 m) governed by a power-law attenuation of fragmentation effects. Pedestrian behavior is parameterized by the Allowable Conflict Coefficient (ACC), the inverse of interpersonal friction, and the Emergency Level (EL), which scales the desired velocity. Extensive simulations under stochastic and targeted impact scenarios reveal a consistent evacuation performance hierarchy: Center (C) > Bottom-Left (BL) > Top-Left (TL) > Bottom-Right (BR) ≈ Top-Right (TR). Exit-proximal damage (TR, BR) increased evacuation time by up to 85% compared with central impacts. Results demonstrate a strong coupling between physical friction and urgency: the “faster-is-faster” effect is maximized under low friction (high ACC), while high friction not only suppresses the benefits of elevated EL but can also induce “faster-is-slower” phenomena under extreme conditions. These findings underscore that optimal evacuation strategies depend critically on both impact location and crowd behavior management, providing actionable insights for emergency planning and highlighting the importance of conflict mitigation in enhancing infrastructure resilience. The proposed framework thus offers a versatile and validated simulation tool for emergency planners to proactively assess and optimize evacuation strategies under various damage scenarios.