Host: The Japan Society of Mechanical Engineers
Name : [in Japanese]
Date : September 03, 2023 - September 06, 2023
Longitudinal ventilation is the mainstream ventilation system for road tunnels in Japan, and in many cases, especially in long tunnels, low-speed ventilation control is introduced to reduce the longitudinal wind velocity near the fire point to as close to 0 m/s as possible. In Nihonbashi underground section, there are many underground buried structures such as sewers and subways, which must be avoided, and therefore there are many steep sections with low inner voids. In such sections, it is difficult to ensure an evacuation environment with conventional low air velocity control because smoke flows in an upward direction, which tends to expand the reachable area, and smoke descends quickly due to a decrease in the retention space. Therefore, a "Sectional smoke extraction system" that concentrates smoke extract airflow only in the vicinity of the fire point and its improvement system were studied. As a result, effective smoke evacuation was achieved even in steep sections with low inner airspace.
