Review on the Configuration of Outlet Duct forAir Supply in a Tunnel - Aiming for Safety Improvement

Abstract

Following the ceiling panel collapse accident in Sasago Tunnel, NEXCO-Central is putting more effort into preventing the recurrence and improving safety. This paper introduces one example of a study to improve the safety of shaft air supply-exhaust type outlet ducts. This study offered multiple proposed improvements to the structure of ducts and performed a comparative study including evaluation of wind conditions in a tunnel by CFD analysis and in-site testing.