Construction method of anti-floating structure of composite prestressed pipe pile with built-in anchor cable filling core

Abstract

The invention relates to a construction method for a combined type prestressed pipe pile anti-floating structure with a built-in anchor cable grouted core. The construction method comprises the following steps that 1, a pilot hole is constructed; 2, a pile-bottom high-pressure spiral spraying expanded body is constructed; 3, a supporting body is connected with a non-bonded anchor cable; 4, the pile tip of a prestressed pipe pile is treated; 5, the supporting body is connected between pile sections, and the anchor cable is installed; 6, static-pressure pile sinking is conducted; 7, pile extension is constructed; 8, a general supporting body at the pile top and an anchor cable are installed; 9, static-pressure pile sinking is conducted; 10, fine aggregate concrete is poured into the inner cavity of the pipe pile; 11, the outer side of the pipe pile is sealed with high-pressure cement paste; and 12, the non-bonded anchor cable is tensioned and locked. According to the construction method, the characteristics of the prestressed pipe pile that the quality is stable and the construction speed is high are brought into full play, the defect that the pull-out capacity of the pipe pile is poor is overcome, the combined type anchor cable structure and pile-side high-pressure grouting are adopted, the anti-floating capacity of the structure is improved substantially, and good technical and economic benefits are obtained.

Description

technical field [0001] The invention relates to a construction method of a prestressed pipe pile anti-floating structure, which belongs to the field of foundation engineering and is suitable for the construction of anti-floating structures in building basements, underground garages, sunken squares, underground shopping malls and other projects in areas with relatively high groundwater. Background technique [0002] With the rapid development of urban construction, a large number of high-rise buildings, underground garages, sunken squares, subways, underground shopping malls and other buildings have put forward higher requirements for the utilization of underground space. However, in coastal cities such as Shenzhen, Dalian, and Qingdao, where the underground soil is rich in water, the buoyancy of the groundwater caused by the buoyancy of the groundwater, the accidents of the superstructure such as buildings and structures tilting and collapsing frequently occur, making the pro...

AI Technical Summary

Problems solved by technology

However, there are also many deficiencies in the anti-floating anchor. First, the longer the anchor, the better the anchoring effect. However, in order to achieve a good anchoring effect in deep soft soil areas, the length of the anchor must increase. Obviously, It increases the difficulty and cost of construction; secondly, longer anchors will inevitably increase the difficulty and quality of grouting, which will affect the anchoring effect; finally, the contribution of anchors to the vertical bearing capacity of the foundation is very limited, and generally other structures need to be installed to bear the vertical bearing capacity

[0004] In the current prestressed anti-floating piles, the prestressed tendons are concentrated in the same stress-bearing section of the pile body, and their lengths are basically the same, while the axial force of the pile body changes along the pile length, so it is impossible to stress each pile body. If the prestress is fully applied, the crack control effect of the pile is not good, the durability of the pile is limited, and the strength of the material cannot be fully utilized, and the overall cost is high

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