Method for constructing seepage prevention system of secondary cofferdam for immersed tube tunnel

Abstract

The invention relates to a method for constructing a seepage prevention system of a secondary cofferdam for an immersed tube tunnel, belonging to the field of constructional engineering. The method includes the following steps: (1) construction and manufacturing of underground continuous walls of a joint section; (2) construction and manufacturing of the main body structure of the joint section; (3) underwater casting of the self-compacting concrete cofferdam; and (4) construction and manufacturing of seepage prevention walls. The invention has the advantages of small processing field, strong controllability of hoisting operation, high construction accuracy, favorable stability of the secondary cofferdam and watertight effect, less security risk, etc.

Description

Technical field: [0001] The invention belongs to the field of construction engineering, and in particular relates to a construction method for a secondary cofferdam anti-seepage system of an immersed tube tunnel. Background technique: [0002] At present, the secondary cofferdam of immersed tube tunnels in China usually adopts concrete block cofferdam, that is, prefabricated concrete blocks are processed in advance, and the blocks are hoisted in layers and blocks. Construction steps of the cofferdam. Since the blocks are of thin-walled structure, there is no possibility of stacking. Therefore, a large processing and stacking site is generally required. Due to the complex construction environment or a certain slope, the construction site generally does not have such conditions, and the main risks are as follows: [0003] 1. Due to the heavy weight of the block itself, there are too many safety risks and uncontrollable factors during hoisting, and the accuracy of the hoistin...

AI Technical Summary

Problems solved by technology

[0003] 1. Due to the heavy weight of the block itself, there are too many safety risks and uncontrollable factors during hoisting, and the accuracy of the hoisting operation cannot be accurately predicted. It is very likely that the last block of each floor cannot be lowered.

[0004] 2. It is also easy to cause block collision during hoisting, thereby destroying the concrete wall of the block, causing it to break, resulting in unpredictable consequences or affecting the construction quality

[0005] 3. The block cannot form an effective whole with the structure on the bottom and both sides, and the stability is poor. Even if there is a structural connection between the bottom and both sides, it is easy to seep water

[0006] To sum up, the construction method of this block cofferdam has difficulties in prefabricating the site, too many uncontrollable factors brought about by hoisting operations, difficult control of construction accuracy, poor stability and water-stop effect cannot be effectively guaranteed, so there are a large number of problems. security risks etc.

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