AN APPROACH TO REDUCE TIE-UPSBY SPEED ADAPTATION AT SAG/TUNNEL SECTIONSON EXPRESSWAYS

摘要

About 50% of the traffic tie-ups in Japan form at the sag/tunnel sections of expressways.The study introduced in this paper has put forward an approach of vehicle speed control as asuitable measure to negotiate sag/tunnel sections. This prevents irregular traffic flow fromforming tie-ups and keeps traffic movement uninterrupted (unbiased lane use) on expressways.A prime example of the conditions that create tie-up formation at sag/tunnel sections isKobotoke tunnel on the Chuo-Expressway. This is exemplary data to use for the trafficsimulator, SIPA (Smart Infrastructure Performance Analyzer). A review using simulation bySIPA on impacts of speed control for tie-up conditions has explicitly proved the validity of thespeed control approach.