Research on Graded Lane Changing in Undersea Tunnel Exit Diversion Zones: Application of Set Pair Analysis and TOPSIS Method for Evaluation

Owing to undersea‐tunnel constraints concentrating off‐ramp maneuvers in confined zones, this study optimizes graded lane‐changing strategies to mitigate collision risks. Using the Jiaozhou‐Bay Undersea Tunnel case, we propose an innovative exit diversion area graded lane‐changing strategy comprising Transition Section I, Transition Section II, gradient section, and auxiliary lane. Six schemes were simulated via UC‐WinRoad, with driver physiological stress quantified through Tobii eye‐tracking as a novel application of pupil dynamics. Four indicators—lane‐change position, lane‐change rate, pupil diameter, and speed change—were weighted by the integrated analytic hierarchy process and entropy weight method (AHP–EWM) methodology and evaluated via the set pair analysis with the technique for order preference by similarity to ideal solution (SPA‐TOPSIS) theory model. Optimal Scheme E (290‐m transition I, 210‐m transition II, 120‐m gradient, and 140‐m auxiliary lane) achieved γ = 0.968, significantly reducing pupil fluctuation by 32% compared with the shortest design (Scheme A) while ensuring smoothest speed control. This demonstrates effective conflict distribution in high‐risk undersea environments, providing universally applicable design benchmarks for tunnel safety enhancement.