Construction Technology Study On Immersion And Connection Of Immersed Tube Under Offshore Conditions

With Bridges and underground running tunnel shield (drilling and blasting method), immersed tube tunnel has its unique advantages, wide adaptability of foundation, tunnel length than the shortest, excellent water proofness and important position in the field of underwater tunnel. With the development of science and technology and the progress of the society, immersed tube tunnel towards the offshore environment, development of large-scale, long distance and direction of deep water, a batch of domestic major channel engineering across the river, the gulf are brewing with the method of immersed tube tunnel. Because of the immersed tube tunnel in mainland China started late, built in the mid-90-Guangzhou Pearl river tunnel is domestic first immersed tube tunnel, so far, has been in Shanghai, Guangzhou, Ningbo, Tianjin and other places to build dozens of inland river immersed tube tunnel, but most of the length is shorter, smaller, the overall level of construction has a certain gap with international similar project.Immersed tube tunnel construction process generally includes base groove excavation, foundation treatment, foundation construction, pipe joint precast, pipe joint and float and sink docking and cover the main working procedure such as backfilling, each procedure according to the actual circumstance of engineering can choose different construction technology, has its different and other forms the unique key technology of the tunnel.This article first discusses immersed tube tunnel and other forms the difference of the tunnel and its advantages and disadvantages, on the basis of collected domestic and international typical construction cases, briefly discusses its advantages in across the estuary and gulf projects, then the division of sequence shows the general construction procedure and technology of the immersed tube tunnel, strive to fully reflect the main course of the development of immersed tube tunnel and the main construction technology. Then, the key to put immersed tube sinking and docking link with research, the key construction technology of full analysis, argumentation and than choose large immersed tube tunnel projects in the pipe joint intro way and the orientation of anchoring and underwater measurement and control and guide, pull close docking, fine line adjustment and end joint of the construction technology and method, proposed the offshore large immersed tube tunnel engineering, the optimal sink docking process method, and successfully applied in the Hongkong-zhuhai-macao bridge immersed tube tunnel construction. Related construction technology can also provide reference for other offshore engineering.