Abstract: This study addresses the controversial issue in current codes regarding the combined use of vehicular cross passages as pedestrian cross passages. Through a comparison of relevant codes, functional positioning analysis, and practical engineering experience, the feasibility and applicability of different cross passage configuration schemes are systematically examined. The study first reviews relevant technical codes and identifies discrepancies in requirements such as configuration methods and fire separation measures. Then, from the perspective of disaster prevention design, and based on the differences in evacuation and rescue scenarios for personnel and vehicles, it concludes that pedestrian and vehicular cross passages should be functionally separated. The study compares and analyzes the implementation effects of three schemes: "combined use" "shared use" and "separate". The results indicate that while the "combined use" scheme offers spatial feasibility, it suffers from unclear functional positioning of the cross passage and insufficient reliability of fire separation facilities. The "shared use" scheme, although adopting an adjacent but separated configuration, significantly increases structural width and construction costs. The "separate" scheme, by independently configuring pedestrian and vehicular cross passages, demonstrates comprehensive advantages in evacuation efficiency, smoke control, and operation and maintenance. The study recommends that the separate layout of pedestrian and vehicular cross passages is a more rational approach for the disaster prevention design of underground road tunnels.

Key words: vehicular cross passage, pedestrian cross passage, combined use, underground road, fire-resistant rolling shutter, fire-rated door