Adaptability-enhanced evacuation path optimization and safety assessment for subway station passengers in floods: From uncertain challenge to reliable escape

Subway stations face an increasingly serious risk of flooding as climate change leads to frequent extreme rainfall events. The suddenness of external flood disasters and the uncertainty of hazard factors have posed severe challenges to the safety and reliability of traditional evacuation plans in complex closed space structures and dense passenger flow environments. To address the above technical demands and problems, we propose a robust path optimization model and safety assessment method for passenger evacuation paths in flood scenarios, aiming to improve escape efficiency and safety while avoiding the sensitivity of the optimization scheme to parameter disturbances. The robust optimization model of the evacuation path constructs the evacuation time and road risk uncertainties through the box-type intersection budget uncertainty sets, so that the optimization strategy can find a balance between efficiency and risk and has strong adaptability; a new QIPSO algorithm is proposed to solve the model; the adopted relative entropy weighting model (REWM) introduces the relative entropy theory into the entropy weighting model, which can reasonably deal with the differences and consistency of different weight vectors among safety evaluation indicators. The performance analysis of the passenger evacuation simulation effect under the environment of flood intrusion in a subway station is carried out. The results show that: (i) the robust path optimization model can seek feasible and reliable evacuation decision-making solutions under the uncertain environment caused by floods; (ii) the designed innovative QIPSO algorithm shows strong potential in reducing evacuation time, alleviating passenger congestion and reducing instability risks when solving the robust model; (iii) the evaluation results based on the REWM further verify that the evacuation path optimization strategy can effectively improve the safety level of the station in dealing with flood risks.