Negative buoyancy immersed tube and prefabricating method thereof

Abstract

The invention relates to the technical field of immersed tube tunnel construction, in particular to a negative buoyancy immersed tube and a prefabricating method thereof. The immersed tube comprises abody, wherein the designed freeboard value of the body is smaller than 0. According to the negative buoyancy immersed tube, pipe joints do not need to be designed to be capable of self-floating in acorresponding water area, therefore, the section height of the immersed pipe does not need to be increased for guaranteeing the minimum freeboard value during floating transportation, the design contradiction between freeboard value consideration and anti-floating in the operation period in the design link is avoided, a dry dock does not need to be set for freeboard value detection, the method isparticularly suitable for engineering projects with limited fields, the design concept that a self-floating immersed tube must be adopted in the prior art is broken through, the structural height canbe reduced to the maximum extent, the engineering amount of a main body structure, foundation trench backfilling and the like is reduced, a freeboard adjusting layer does not need to be arranged, theprefabricating cost and the construction cost are effectively reduced, design difficulty and prefabricating difficulty are reduced, the cumbersome operation of adjusting the freeboard value in water in the floating transportation link is avoided, the transportation time can be shortened, and the method has important popularization significance and good application prospects.

Description

technical field [0001] The invention relates to the technical field of immersed tube tunnel construction, in particular to a negative buoyancy immersed tube and a prefabrication method thereof. Background technique [0002] The buoyancy design must be considered in the structural design of the immersed tube, including the selection of the freeboard and the checking calculation of the anti-floating safety factor. The prefabrication of immersed pipes in the prior art mainly includes the dry dock method and the factory method. Due to the high prefabrication efficiency of the factory method, it is often suitable for projects with a tight construction period. At present, no matter what kind of prefabrication method is used, the positive freeboard pipe joint is used, that is, when the pipe joint is floating, the pipe joint can float in the water, and the top surface of the pipe joint must be exposed to the water surface. In order to ensure the safety and stability of the pipe joi...

AI Technical Summary

Problems solved by technology

[0004] The purpose of the present invention is to overcome the need to meet the minimum freeboard value in the design of immersed tubes in the prior art, resulting in a large cross-sectional height of the pipe joint, which in turn increases the amount of engineering work such as the main structure and foundation groove backfill, and increases the cost of prefabrication and construction. The above-mentioned shortcomings of large and difficult construction provide a negative buoyancy immersed tube and its prefabrication method

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