FRP pipe-PHC pipe pile interlayer in-fill concrete combined structure

Abstract

The invention discloses an FRP pipe-PHC pipe pile interlayer in-fill concrete combined structure. The FRP pipe-PHC pipe pile interlayer in-fill concrete combined structure comprises an FRP pipe serving as the outer side wall, a PHC pipe pile core pipe serving as the inner side wall and a concrete layer poured between the FRP pipe and the PHC pipe pile core pipe, and a hollow pipe pile is composedof the FRP pipe, the PHC pipe pile core pipe and the concrete layer. By means of the FRP pipe-PHC pipe pile interlayer in-fill concrete combined structure, due to the fact that the FRP pipe is wrappedon the outer side of the PHC pipe pile core pipe, the corrosion resisting performance of the structure is improved; and in addition, the FRP pipe and fill concrete are wrapped on the outer side of the PHC pipe pile core pipe, transverse constraint is then applied to the core concrete of the structure, the concrete is in a three-item stressed state, the bearing capability and the bending rigidityof the pipe pile are improved, expanding of a longitudinal micro crack of the pipe pile is relieved, and therefore durability and anti-seismic performance of the pipe pile are improved.

Description

technical field [0001] The invention relates to marine engineering and other pile foundation projects with high requirements on corrosion resistance and durability, in particular to a composite structure filled with concrete in an FRP pipe-PHC pipe pile interlayer. Background technique [0002] In actual engineering, PHC pipe piles are more and more widely used in the construction of high-rise buildings, bridges, ports, wharves and other projects. Technicians usually think that centrifugal concrete has good compactness and high concrete strength, and the durability of pipe piles can fully meet the requirements of corrosion-resistant media. Designers seldom consider the requirements for the use of pipe piles under specific corrosion conditions, so that There are hidden dangers in the durability of pipe pile engineering. Taking the Hangzhou Bay Bridge as an example, it adopts the design concept of "pile-collecting piers", and each pier as a basic structure consists of 10-12 s...

AI Technical Summary

Problems solved by technology

However, this method wastes a lot of steel, has high manufacturing and installation costs, and has a long construction period. It is not an economically feasible, long-term corrosion control method.

The Hangzhou Bay Bridge adopts the design concept of three-layer high-performance fusion-bonded epoxy coating to prevent corrosion of pipe piles, but the coating still has problems such as local damage, peeling off, and the service life of the coating is lower than the design life of pipe piles.

In addition, for other offshore projects that directly use PHC pipe piles as the foundation, chlorides in seawater can pass through the gaps in the concrete surface and contact the steel bars. Due to the highly alkaline environment of the concrete, the steel bars will be passivated. This will cause corrosion in local areas, and finally due to the internal pressure generated by rust, the concrete will fall off and break, which will affect the performance of pipe piles and affect the safety of the structure

Therefore, when pipe piles are used in marine engineering, there are still problems of insufficient durability and corrosion resistance, which leaves a great safety hazard for the project

Images