For the Maiko Tunnel, tunnel ventilation facilities are installed on the up and down lines to eliminate dust generated from passing vehicles, in order to preserve the environment in the surrounding area. Among them, the dust removal system adopts a filter system in which a panel-type pre-filter is placed at each inlet of a blower, and dust included in the air is trapped and collected. At the HSBE Expressway, the atmospheric pressure filter washing device has been renovated into a newly-developed water-jet (WJ) regeneration equipment in an effort to reduce costs.

The water jet (WJ) regeneration equipment is composed of a high pressure water generator, a nozzle header, a moving device, a control device and a sewage treatment facility. Pump operation and nozzle movement are automatically performed by pressing the washing start switch on the touch screen of the control panel. In addition, generated wastewater will be processed by filtration treatment in a wastewater treatment facility.

For long tunnels, a water spray facilities capable of discharging water simaltaneously, are installed along every 50m for the purpose of initial fire extinguishing on vehicles. Previously, the water discharge inspection for the facility was carried out by road closing and direct water discharge, or implementing traffic lane regulation and measured by a dedicated measurement vehicle. Direct water discharge required a great deal of cost and time to secure a detour route for general traffic vehicles and public relations activities, and the procurement of dedicated measurement vehicles caused substantial initial costs.

For this reason, we have developed a simple flow measurement device for tunnel water spray equipment that can measure the amount of water discharged per head easily and inexpensively. The device is composed of a light truck loaded with general-purpose high elevation vehicles and inspection equipment. And safe water discharge inspection is possible with lane traffic regulation and without water scattering.