Hong Kong-Zhuhai bridge foundation to achieve the first docking bridge Island

Hong Kong-Zhuhai bridge foundation to achieve the first docking bridge Island

Recently, the Hong Kong-Zhuhai-Macao Bridge, the 16th heaviest pier pier successful device. The pier is an important connection point to Hong Kong-Zhuhai-Macao Bridge, the main bridge between the West and the artificial island project, weight 3500 tons, lifting the weight of more than 3900 tons. Piers minister 24.5 m wide and 5 m in the shape of a dumbbell-shaped, increasing the difficulty of lifting design. Successful device pier, the Hong Kong-Zhuhai bridge marks the foundation realized the first bridge island docking.

Hong Kong-Zhuhai-Macao Bridge is a huge bridge connecting Hong Kong, Zhuhai and Macao in promoting further development with Hong Kong, Macau and the Pearl River Delta economic region on the west coast of strategic importance. Hong Kong-Zhuhai-Macao Bridge project was to create a body December 15, 2009 to start the construction of the first phase was completed in 2015 to 2016, the bridge invested over 70 billion yuan, about 6 years completed. 20,102,013 on April 21, 2009, is located in Shan Tau Island precast plant successfully completed its first undersea tunnel standard pipe section. May 6, 2013, the first section of the immersed tube tunnel subsea equipment, July 30, 2013, the first section of 180 m pipe sections subsea equipment, marking the deep tunnel device fully open.

Hong Kong-Zhuhai-Macao Bridge, the principle of creating an immersed tube tunnel

Hong Kong-Zhuhai-Macao Bridge, a total length of nearly 50 km, of which part of the sea bridge and tunnel about 35.6 km, about 6.7 km tunnel part, because of the complex geological and water blocking the bridge to reduce the rate and other factors, there is no choice of authentic part of the shield law to create authentic, and immersed tube method chosen to create authentic.

Immersed tube method first need to create an authentic pre-sink pipe section. Shen pipe section is divided into sections and non-standard pipe tube sections, use of prefabricated factory production in the workshop. Standard pipe section 180 meters long and weighs about 75,000 tons. When prefabricated pipe sections each section will be 180 m long section of heavy pipe section is divided into eight small tubes, each small tube section 22.5 meters long, a whole section Shen prefabricated pipe weighs about 75,000 tons. The interface of each small tube sections are optional bump slot design, a small tube protruding sections where the bite with the addition of a small tube section sunken place to ensure that small tube section does not fall off after pulling together. Between each small tube sections are optional stop, to prevent water leakage.

After a heavy pipe in the following section prior device good 256 hydraulic jacks, prefabricated pipe sections to achieve the top launch workshop. This 256 hydraulic jacks, and 192 500 tons (the actual weights of up to 900 tons) is responsible for the immersed tube jack hold another 64 jack, is responsible for the immersed tube to push forward, push the immersed tube to light dock areas.

Immersed tube device in a shallow dock area ballast water system. Immersed tube inside the tank is divided into six, leaving a gap between the six tanks, and pipes are connected. After relying on water to the tank to control the sink and drain tube floating and sinking when Shen and Shen pipe in the middle of the tunnel ventilation, lighting facilities and pipelines in advance for a good device. After all the equipment unit to be good, to the dock area in shallow water, control surface immersed tube about 15 cm, and left entrance at the top of the immersed tube, staff can enter through this entrance examination immersed tube inside.

In shallow dock area is also an important task is to test the quality of the concrete pouring sink pipe sections, water stop compression function of each part of the sealing function and various small tube between sections and so on.

Immersed tube in a shallow dock area after detecting passing dock area and closed the gates of deep sea between. After the deep water dock area, immersed tube from shallow to deep dock Floating dock area storage area, and wait for the sea.

In the immersed tube prefabricated, while also simultaneously in the offshore construction. Immersed tube tunnel laid on the seabed soft soil. Foshan Steel to ensure the smooth and solid foundation, you need more than 40 meters underwater excavation of an error can not be more than 2 cm base slot. In order to reduce the settlement after the immersed tube device, to play five or six square root of 1.2 meters in diameter at the base of sand compaction pile tank, sand pile bottom straight to the hard soil more than 20 meters deep.

Also, the tank has been excavated to make a good base gravel subgrade foundation, that is, to the laying of a 42 m wide in the sea, 30 cm thick layer of gravel flat. Needs of each stone is about 2-6 cm in diameter, and the flatness error of this gravel layer to be controlled in less than 4 cm. To ensure the quality of construction gravel layer, builders have developed a similar "fixed offshore drilling platform" leveling riprap ship, the vessel can be gravel through a catheter straight Scientology slot.