Knowledge about Traffic Signs (1)
Tunnel Traffic Signs, also known as tunnel electro-optic signs, are mainly used in tunnels as a traffic safety facility to indicate tunnel safety. It is a luminous sign with certain graphics and symbols that can be clearly recognized in dim light.
1. Background of Traffic Signs
With the gradual improvement of expressway construction in plain areas, hilly areas and economically developed areas in various provinces and cities, the focus of expressway construction is gradually shifting to mountainous areas and mountainous areas with relatively lagging economic development. There are more and more long tunnels and extra-long tunnels. Due to their concealed belt-like structure, the tunnels have brought a series of changes to the traffic driving environment, especially for long tunnels on highways with large traffic volumes. Serious, once caused great losses due to security issues.
As the road tunnel is a closed space, the traffic space is limited, and the air is not easy to circulate. The original reflective Traffic Signs will soon lose the reflective effect due to air pollution in the tunnel. In order to better indicate the traffic safety in the tunnel , Tunnel Electric Traffic Signs was created under such a background.
2. Existing types
At present, the Ministry of Communications has promulgated the "Code for Design of Highway Tunnel Traffic Engineering" (JTG/T D71-2004) to make regulations on the electro-optical signs in tunnel Traffic Signs, which are mainly divided into emergency signs, fire equipment signs, and pedestrian cross holes. Directional sign, emergency stop strip sign, evacuation sign.
2.1 Indicate Traffic Signs and Fire Equipment Indication Signs
Emergency indication Traffic Signs are used to indicate the emergency position in the tunnel, and fire equipment indication Traffic Signs are used to indicate the position of fire equipment in the tunnel. The layout of the sign is generally 25cmX40cm, which can be adjusted according to the clearance of the tunnel design.
2.2 Pedestrian crossing, driving crossing, emergency parking with Traffic Signs
Traffic Signs are used to indicate the position of the pedestrian crossing in the tunnel, and indicate the escape route for people in the tunnel when an emergency occurs in the tunnel; The vehicle diverts to the driving cross hole; the emergency stop belt sign is used to indicate the location of the emergency stop belt in the tunnel. The layout of the logo is generally 50cmX80cm, which can be adjusted according to the clearance of the tunnel design.
2.3 Evacuation Instructions Traffic Signs
Evacuation instruction Traffic Signs are used to indicate the distance and direction from the point to the entrance, the cross-hole for traffic, and the cross-hole for pedestrians, and to instruct pedestrians and vehicles to leave quickly when an emergency occurs in the tunnel.
illustrate:
1) The layout of the electro-optic sign is limited by the clearance of the tunnel, so the layout design is mainly based on graphics.
2) The brightness of the electro-optic sign is greater than 15-300cd/m2
3) The box body is made of corrosion-resistant materials, such as galvanized steel plate and aluminum alloy material, and the protection level is not less than IP65. Tubes, made into light boxes, are the earliest electro-optic Traffic Signs.
Its disadvantages are:
1. The volume is bulky, the cost is high, and the transportation and installation are difficult.
2. The internal lamp is easy to burn out and difficult to replace.
3. The sign cannot reflect light. Once the internal circuit fails, the sign will lose its warning function.
4. The sealing is not good. When the high-pressure water gun cleans the tunnel, the internal circuit is easy to short circuit. So the application is very limited.
