Composite lubricating sleeve with effect of reducing pile sinking soil plug

Abstract

The invention discloses a composite lubricating sleeve with a pile sinking soil plug reducing effect. The device comprises a flexible substrate and a microstructure anti-drag layer which are compounded together, the outer circumferential face of the flexible base is attached to the inner circumferential face, close to a pile shoe, of a prefabricated pipe pile, and solid lubricating particles are evenly mixed in the flexible base. The microstructure resistance reduction layer is composed of a plurality of micro convex points which are regularly distributed on the inner circumferential face of the flexible substrate in a dot matrix shape, and solid lubricating particles are packaged in the micro convex points. According to the method, the pile sinking construction difficulty and equipment requirements can be effectively reduced, pile body deviation and equipment energy consumption caused by too large resistance are reduced, and the construction cost is directly saved. The core innovation of the method lies in that the blocking forming process is actively intervened through a multiple cooperation mechanism of solid particle lubrication, micro-convex-point blocking and micro-rolling, the controllability of the pile sinking process and the perpendicularity of a pile body are greatly improved, and the pile sinking quality is improved from the source. The composite lubricating sleeve is unique in technical path, and the technical span from passive treatment to active prevention and control is achieved.

Description

Technical Field

[0001] This invention belongs to the technical field of auxiliary equipment for precast pipe pile construction in civil engineering, and specifically relates to a composite lubricating sleeve for precast pipe pile driving operations, which reduces the soil plugging effect and lowers the pile-soil friction resistance through a combination of methods. Background Technology

[0002] Precast pipe piles are widely used in foundation construction for ground reinforcement. They are typically driven into the soil using methods such as hammer driving or static pressure. However, during penetration, soil resistance can cause soil plugs to form inside the precast pipe pile, significantly increasing the penetration force, thus increasing construction costs, extending the construction period, and even affecting the quality of the pile foundation. Currently, high-pressure water jetting is commonly used on construction sites to remove these soil plugs, but these methods are time-consuming, labor-intensive, and carry certain construction risks. Therefore, how to reduce the impact of soil plug formation within precast pipe piles has become a pressing issue for the industry. Summary of the Invention

[0003] To address the aforementioned problems, the present invention aims to provide a composite lubricating sleeve that reduces soil plugging during pile driving.

[0004] To achieve the above objectives, the composite lubrication sleeve provided by the present invention for reducing soil plugging during pile driving includes a flexible base and a microstructure drag-reducing layer bonded together; wherein the outer circumferential surface of the flexible base is attached to the inner circumferential surface of the precast pipe pile near the pile shoe, and solid lubricating particles are uniformly mixed inside; the microstructure drag-reducing layer is composed of multiple micro-protrusions regularly distributed in a lattice on the inner circumferential surface of the flexible base, and solid lubricating particles are encapsulated within the micro-protrusions.

[0005] The flexible base of the composite lubricating sleeve, which has the function of reducing soil plugging during pile driving, is attached to the precast pipe pile using an adhesive.

[0006] The composite lubricating sleeve with the function of reducing soil plugging during pile driving also includes a fixing ring that fixes the lower edge of the flexible base to the starting end of the inner wall of the precast pipe pile located on the upper side of the pile shoe.

[0007] The flexible substrate is made of a high-strength, high-elasticity thermoplastic polyurethane film.

[0008] The micro-bumps constituting the drag-reducing layer are formed on the inner circumferential surface of the flexible substrate using a molding process.

[0009] The solid lubricating particles are made of nanoscale silicon dioxide, graphene, or special polymer powders.

[0010] The solid lubricating microparticles are encapsulated inside microbumps using microencapsulation technology.

[0011] The composite lubrication sleeve with the function of reducing soil plugging during pile driving provided by the present invention has the following beneficial effects:

[0012] This technology effectively reduces the difficulty and equipment requirements of pile driving, minimizes pile displacement and equipment energy consumption caused by excessive resistance, and directly saves construction costs. Its core innovation lies in its proactive intervention in the blockage formation process through a multi-pronged synergistic mechanism of solid microparticle lubrication, micro-protrusion isolation, and micro-rolling. This significantly improves the controllability of the pile driving process and the verticality of the pile, fundamentally enhancing pile driving quality. This composite lubrication sleeve technology has a unique approach, achieving a technological leap from passive treatment to proactive prevention. Attached Figure Description

[0013] Figure 1 A schematic diagram of the usage state of the composite lubrication sleeve that reduces the soil plugging effect of pile driving provided by the present invention. Detailed Implementation

[0014] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments.

[0015] like Figure 1 As shown, the composite lubrication sleeve with the function of reducing soil plugging during pile driving provided by the present invention includes a flexible base 2 and a microstructure drag-reducing layer that are composited together; wherein the outer circumferential surface of the flexible base 2 is attached to the inner circumferential surface of the precast pipe pile 1 near the pile shoe, and solid lubricating particles 5 are uniformly mixed inside; the microstructure drag-reducing layer is composed of a plurality of micro protrusions 4 that are regularly distributed in a dot matrix on the inner circumferential surface of the flexible base 2, and solid lubricating particles 5 are encapsulated in the micro protrusions 4.

[0016] The flexible base 2 on the composite lubricating sleeve, which has the function of reducing soil plugging during pile driving, is attached to the precast pipe pile 1 using an adhesive.

[0017] The composite lubricating sleeve with the function of reducing soil plugging during pile driving also includes a fixing ring 3 that fixes the lower edge of the flexible base 2 to the starting end of the inner wall of the precast pipe pile 1 located on the upper side of the pile shoe.

[0018] The flexible substrate 2 is made of high-strength, high-elasticity thermoplastic polyurethane film (TPU).

[0019] The microbumps 4 that constitute the drag-reducing layer of the microstructure are formed on the inner circumferential surface of the flexible substrate 2 by molding process.

[0020] The solid lubricating particles 5 are made of nanoscale silicon dioxide, graphene, or special polymer powder.

[0021] The solid lubricating microparticles 5 are encapsulated inside the microbumps 4 using microencapsulation technology.

[0022] The installation and working principle of the composite lubrication sleeve with the function of reducing soil plugging during pile driving provided by the present invention are described below:

[0023] Before driving the precast pipe pile 1 in the factory or on the construction site, the prepared composite lubricating sleeve roll is first unrolled, and then the outer surface of the flexible base 2 on it is pasted to the inner circumference of the precast pipe pile 1 near the pile shoe using an adhesive. Alternatively, the lower edge of the flexible base 2 can be fixed to the starting end of the inner wall of the precast pipe pile 1 located on the upper side of the pile shoe using a fixing ring 3. This ensures that the composite lubricating sleeve will not fall off when subjected to soil friction during the pile driving process.

[0024] When the precast pipe pile 1 is driven into the soil, the soil entering the precast pipe pile 1 first comes into contact with the dot-matrix micro-protrusions 4 on the surface of the composite lubrication sleeve, resulting in compression and friction. The structure of the micro-protrusions 4 can effectively disperse and reduce the initial contact area and normal pressure between the soil and the pipe wall. As the pile is driven deeper, the mechanical stress and heat generated by friction will cause the solid lubricating particles 5 inside the micro-protrusions 4 and its flexible base 2 to be slowly released and dispersed to the friction interface, forming a lubricating film at the friction interface, thereby gradually transforming the sliding friction into a low-resistance mixed friction state. At the same time, the structure of the micro-protrusions 4 itself can effectively block or reduce the direct, large-area contact between the soil and the pipe wall, decomposing the continuous sliding friction into discontinuous local contact and possible micro-rolling transmitted through the micro-protrusions 4. Thus, the system synergistically forms a triple or even multiple drag reduction mechanism of solid particle lubrication + microstructure physical isolation + micro-rolling, fundamentally weakening the closure tendency of the soil and significantly reducing the pile driving resistance.

Claims

1. A composite lubrication sleeve with the function of reducing soil plugging during pile driving, characterized in that: The composite lubrication sleeve includes a flexible base (2) and a microstructure drag-reducing layer that are combined together; wherein the outer circumferential surface of the flexible base (2) is attached to the inner circumferential surface of the precast pipe pile (1) near the pile shoe, and solid lubricating particles (5) are uniformly mixed inside; the microstructure drag-reducing layer is composed of multiple micro-protrusions (4) that are regularly distributed in a lattice on the inner circumferential surface of the flexible base (2), and solid lubricating particles (5) are encapsulated in the micro-protrusions (4).

2. The composite lubrication sleeve with the function of reducing soil plugging during pile driving as described in claim 1, characterized in that: The flexible base (2) on the composite lubricating sleeve that has the function of reducing pile driving soil plugging is attached to the precast pipe pile (1) with adhesive.

3. The composite lubrication sleeve with the function of reducing soil plugging during pile driving as described in claim 1, characterized in that: The composite lubricating sleeve with the function of reducing pile driving soil plugging also includes a fixing ring (3) that fixes the lower edge of the flexible base (2) to the starting end of the inner wall of the precast pipe pile (1) located on the upper side of the pile shoe.

4. The composite lubrication sleeve with the function of reducing soil plugging during pile driving as described in claim 1, characterized in that: The flexible substrate (2) is made of a high-strength, high-elasticity thermoplastic polyurethane film.

5. The composite lubrication sleeve with the function of reducing soil plugging during pile driving as described in claim 1, characterized in that: The microbumps (4) that constitute the drag-reducing layer of the microstructure are formed by molding on the inner circumferential surface of the flexible substrate (2).

6. The composite lubrication sleeve with the function of reducing soil plugging during pile driving as described in claim 1, characterized in that: The solid lubricating particles (5) are made of nanoscale silicon dioxide, graphene or special polymer powder.

7. The composite lubrication sleeve with the function of reducing soil plugging during pile driving as described in claim 1, characterized in that: The solid lubricating microparticles (5) are encapsulated inside the microbumps (4) using microcapsule technology.

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