The adaptive ventilation control in case of emergency for Shorenji-gawa tunnel

Abstract

Hanshin Expressway Company Limited has placed the Route 2 Yodogawa-sagan Route (1^st stage) in service since 25 May, 2013. A large part of the Route is a two-tube tunnel structure. This tunnel named “Shorenji-gawa Tunnel” is a 3.569km-long urban tunnel in a residential area, and has an on and off ramp in each tube. As the traffic signals installed at the off ramps may cause traffic congestion in the tunnel, we had to consider traffic conditions both in free flow and congestion when we designed the strategy of ventilation control. We have established an adaptive ventilation control system using inverter driven jet fans and CCTV cameras successfully. Some of the CCTV cameras have an automatic image processing function, it is possible to identify the areas of congestion accurately. The target value of air flow velocity in case of a fire is 0 (m/s) if congestion exists forward the fire point; otherwise it is 2 (m/s).