On June 30th, the Qingdao Jiaozhou Bay Bridge, which spans 36.48 kilometers in Jiaozhou Bay, and the Qingdao Jiaozhou Bay Tunnel, which is 9.47 kilometers long across the Jiaozhou Bay, was opened to traffic in Qingdao. According to public information, the Qingdao Jiaozhou Bay Bridge is 0.48 kilometers longer than the longest Hangzhou Bay Bridge in the world. Qingdao Jiaozhou Bay Tunnel is 0.77 kilometers longer than the longest Xiamen Xiang'an Submarine Tunnel in China.
It is understood that the entire Jiaozhou Bay tunnel project in Qingdao uses LED tunnel lights for lighting. The number of lamps used is about 6,500 sets. It is the largest project for LED lighting in single tunnels worldwide. It is also the current use of LED tunnel lighting for global use. The length of the tunnel is second only to the construction of the Shanghai Yangtze River Tunnel (the tunnel is 8.9 kilometers long). The LED tunnel lights in the tunnel are all provided by Guangdong Zhonglong Transportation Technology Co., Ltd.
The brightness of the light in the tunnel is designed according to the “Summer Cloudy” standard, which not only ensures the lighting needs but also fully considers the energy saving and environmental protection needs. The LED lamps at both ends of the tunnel have the highest density and the strongest light. The brightness of each lamp is more than 200 watts. When the transition to the middle, the light gradually weakens, and the middle section of the tunnel is reduced to 70 watts. This design takes into account the driver's visual experience. At both ends of the tunnel, the natural light is involved, and the light in the tunnel needs to be strong to ensure the driver adapts. After entering the tunnel for 3 seconds (about 100 meters), the driver has adapted to the environment inside the tunnel, and the lights are gradually weakened according to the 100-meter standard. When the tunnel is out, the lighting is gradually strengthened to ensure safe driving.
Different from the general mountain tunnel, the sea fog in the submarine tunnel is more corrosive. Therefore, the sealing performance of the LED lamps installed in the tunnel is the highest level, ensuring that the LED lamps will not shorten the service life due to sea fog corrosion.
The Qingdao Jiaozhou Bay Tunnel and its wiring project is 9.47 kilometers long, of which the tunnel length (into the opening to the exit, the right tunnel) is 7.808 kilometers, and the cross-sea area is 4.095 kilometers. The total estimated investment of the project is 7.062 billion yuan. The tunnel started construction in August 2007, and the service tunnel was completed in December 2009. In April 2010, the main tunnel sea area was connected. It has two-way six lanes and a design speed of 80 km/h. The maximum excavation width of the tunnel is 18.3m, the maximum excavation height is 13.5m, the maximum cross-sectional area is 202.2 m2, the deepest is 82.8 meters below sea level, the minimum buried depth of the vault is 2.2m, and the average buried depth is about 16m. After opening to traffic, it will become the fastest route connecting Qingdao to Huangdao, and it is also an all-weather cross-sea passage.