Latch steel pipe pile cofferdam construction method

Abstract

The invention discloses a latch steel pipe pile cofferdam construction method. Through searching of a bending moment balance point, a rock inserting depth is calculated, and meanwhile, the material stress is within a safety value; before a steel pipe pile is inserted, a hole is led firstly, then, the steel pipe pile is inserted in, and anchoring concrete is cast in a pipe until a cofferdam is gathered, so that the problem of incapability of inserting the latch steel pipe pile into rock or incapability of stabilizing the steel pipe when a covering layer is shallow is solved, and the problems ofbottom permeation of the latch steel pipe and insufficient anchoring force in a rock layer are solved; in deep water rock layer excavation, such high-risk operations as underwater blasting and underwater excavation are prevented; for a steel cofferdam, steel can be fully recovered; and pouring of bottoming concrete is canceled to save materials.

Description

technical field [0001] The invention relates to the fields of water conservancy and hydropower, highways, railways, and municipal engineering, and shale construction below the river bed surface, in particular to a construction method for locking steel pipe pile cofferdams. Background technique [0002] When a bridge crosses a wide water area, its foundation is often located in deep water. For deep-water foundation construction, it is usually necessary to install cofferdams or operating platforms before pile foundation punching or foundation excavation can be carried out. According to the position of the bridge cap foundation in the river bed, water depth, geological conditions, etc., different cofferdam forms will be selected. . [0003] When the cap is located on the surface or inside of a deep-water river bed, and there is a large amount of overburden in the river bed, double-wall steel cofferdams and locking steel pipe pile cofferdams are usually used. [0004] The doub...

AI Technical Summary

Problems solved by technology

Limited by the power of the vibrating hammer, the rigidity of the steel pipe itself, reverse friction and other factors, this installation method can only be used in river beds or soil layers with thick covering layers, and cannot pass through hard rock layers.

In Southwest China, the geological distribution of the river bed is often cover layer + rock layer, and the thickness of the cover layer is not uniform. When the cover layer is thin, it cannot provide sufficient anchoring force and stability for steel pipe piles; while the underlying rock The sex is complicated, the softness and hardness are uneven, and it cannot be inserted into the inside

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