Explosive expansion pile tip

Abstract

The invention provides an explosive expansion pile tip which comprises a one-way non-return cover, a flexible bag and a steel pile tip body. The one-way check valve comprises a valve plate and a supporting plate, and the valve plate is installed in the middle of the supporting plate through an elastic reset mechanism. The supporting plate is fixed to a grouting opening in the top of the flexible bag, and the bottom of the flexible bag is fixed to the steel pile tip. According to the explosive expansion pile tip, through the explosive expansion principle, the pile end is expanded, meanwhile, the soil layer at the pile end is compacted, the bearing capacity of the pile end is greatly improved, and pile settlement is reduced. Compared with a traditional technology for tamping carrier piles in prefabricated hollow piles, the speed is high, and labor is saved. And meanwhile, due to the design of the one-way check valve, backflow of the slurry can be effectively prevented in the grouting stage, and the one-way check valve serves as a carrier of the explosion expansion material, so that storage and concentrated detonation of the internal explosion expansion material are facilitated.

Description

Technical Field

[0001] The invention relates to the technical field of steel structures, and in particular to an explosively expandable pile tip. Background Art

[0002] Post-grouting technology for prefabricated piles is a technology developed in recent years. It uses the cavity in the middle of prefabricated hollow piles (pipe piles or hollow square piles) to pre-bury grouting pipes, which can greatly improve the bearing capacity of the soil layer at the pile end and near the pile end, thereby greatly improving the bearing capacity of a single pile and reducing pile foundation settlement. However, it has disadvantages such as difficult to control the quality of grouting and long construction time. The technology of ramming carrier piles in prefabricated hollow piles uses the cavity in the pile core for carrier construction, which can also greatly improve the bearing capacity of a single pile and reduce pile foundation settlement. The quality is easy to control, but the construction of the carrier is slow. Each pile needs to be rammed 200 to 300 times. The construction time of each carrier is about 2 hours, which requires more working hours. Summary of the invention

[0003] The purpose of the present invention is to provide an explosively expandable pile tip for the bottom of a prefabricated hollow pile, thereby greatly improving the pile end bearing capacity of the prefabricated pile and reducing pile settlement.

[0004] To achieve the above object, the present invention provides an explosively expandable pile tip, comprising a one-way check cover, a flexible bag and a steel pile tip;

[0005] The one-way check valve comprises a valve plate and a support plate, wherein the valve plate is mounted on the middle part of the support plate through an elastic reset mechanism;

[0006] The support plate is fixed to the grouting port on the top of the flexible bag, and the bottom of the flexible bag is fixed to the tip of the steel pile; the middle part of the valve plate is raised, and the raised part is filled with explosive expansion material toward one side of the flexible bag.

[0007] Furthermore, the elastic reset mechanism is an elastic arm, one end of the elastic arm is fixed on the support plate, and the other end of the elastic arm is fixed on the valve plate.

[0008] Furthermore, the support plate is an annular steel plate, the valve plate is a circular steel plate, and after the valve plate is placed in the middle of the support plate, a certain gap is reserved between the side edge of the valve plate and the inner wall of the support plate.

[0009] Further, the steel pile tip includes a base plate and a cross-shaped pile tip located at the bottom of the base plate;

[0010] The bottom of the flexible bag is fixedly connected to the bottom plate.

[0011] Furthermore, a circle of legs is provided on the side of the support plate facing the tip of the steel pile. Before the explosion, the legs are supported on the surface of the bottom plate. Oblique side plates are provided between the legs to form a space for accommodating the flexible bag in a folded state.

[0012] Furthermore, the upper surface of the one-way check cover is welded and fixed to the bottom of the prefabricated hollow steel pile.

[0013] Compared with the prior art, the advantages of the present invention are:

[0014] 1. The explosively expandable pile tip of the present invention expands the pile end and compacts the soil layer at the pile end through the explosive expansion principle, greatly improving the bearing capacity of the pile end and reducing pile settlement. Compared with the traditional prefabricated hollow pile internal ramming carrier pile technology, it is fast and saves labor.

[0015] 2. The container is easy to make, can be mass-produced, and can be reliably connected to prefabricated hollow piles.

[0016] 3. The design of the one-way check valve can effectively prevent the backflow of slurry during the grouting stage, and at the same time use it as a carrier of explosive expansion materials, which is convenient for the storage and centralized detonation of internal explosive expansion materials.

[0017] 4. By setting a space for accommodating the flexible bag between the one-way check cover and the steel pile tip, the overall structure is stronger and more beautiful at the factory stage; at the same time, the overall rigidity can also be guaranteed during the embedded stage. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 Schematic diagram of the use status of the explosively expandable pile tip and the prefabricated hollow pile in the embodiment of the present invention;

[0019] Figure 2 It is a composition and exploded perspective view of the explosively expandable pile tip in an embodiment of the present invention;

[0020] Figure 3 It is a schematic diagram of the folded state of the flexible bag in the explosively expandable pile tip according to an embodiment of the present invention;

[0021] Figure 4 It is a schematic diagram of the grouting state of the explosively expandable pile tip after explosive expansion in an embodiment of the present invention. DETAILED DESCRIPTION

[0022] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be further described below.

[0023] The present invention provides an explosively expandable pile tip, such as Figure 1 As shown, it is mainly used to be fixed at the bottom of the prefabricated hollow pile 1 to improve the bearing capacity of the pile end and reduce the pile settlement.

[0024] Specifically, the explosively expandable pile tip is composed of a one-way check cover, a flexible bag 6 and a steel pile tip; the one-way check valve includes a valve plate 2 and a support plate 3, and the valve plate 2 is installed in the middle of the support plate 3 through an elastic reset mechanism; in this embodiment, the support plate 3 is an annular steel plate, the valve plate 2 is a circular steel plate, and the valve plate 2 is installed in the middle of the support plate 3, such as Figure 2As shown, a certain gap is reserved between the side edge of the valve plate 2 and the inner wall of the support plate 3 to ensure that the valve plate 2 can be displaced downward under the pressure of the slurry during the grouting stage to avoid affecting the grouting.

[0025] In this embodiment, the elastic reset mechanism is an elastic arm, one end of which is fixed on the support plate 3, and the other end is fixed on the valve plate 2. The valve plate 2 moves downward under the pressure of the slurry to ensure that the slurry can be poured into the flexible bag 6. When the slurry is not poured, the elastic arm returns to the middle of the support plate 3 under the reset drive of the elastic arm to avoid slurry backflow. Figure 2 As shown, a bulge is provided in the middle of the valve plate 2, and the bulge is filled with the explosive material 4 on the side facing the flexible bag 6, so as to facilitate the storage and centralized detonation of the internal explosive material 4.

[0026] In this embodiment, if Figure 3 As shown, the grouting port on the top of the flexible bag 6 is fixed to the support plate 3 by welding or bolts, and the welding is mainly performed by pre-installing an iron ring on the top of the flexible bag 6 and then welding it to the support plate 3. The bottom of the flexible bag 6 is welded or bolted to the steel pile tip.

[0027] In this embodiment, the steel pile tip includes a bottom plate 7 and a cross-shaped pile tip 8 located at the bottom of the bottom plate 7; the bottom of the flexible bag 6 is fixedly connected to the bottom plate 7. A circle of legs 5 is provided on the side of the support plate 3 facing the steel pile tip. Before the explosion, the legs 5 are supported on the surface of the bottom plate 7; oblique side panels are provided between the legs 5 to form a space for accommodating the folded flexible bag 6; at the factory stage, it is more beautiful to wrap the flexible bag 6 in the space. At the same time, the legs 5 also play a supporting role between the one-way check cover and the steel pile tip, and play a supporting role in the pre-embedded stage of the pile tip to prevent deformation. The flexible bag 6 is polyester fiber. In other embodiments, the flexible bag 6 can also be made of nylon, polyurethane, polyurethane fabric, polyamide, rubber and other materials.

[0028] The working principle of the present invention is: after the prefabricated hollow pile 1 is sunk, the explosive expansion material 4 is detonated. Figure 1 and Figure 4 As shown, the flexible bag 6 expands and squeezes the soil at the pile end, and then the structural filler is poured into the expanded flexible bag 6 through the grouting pipe in the prefabricated hollow pile 1. After the flexible bag 6 after the pile is sunk is expanded, grouting is poured into the flexible bag 6 to improve the bearing capacity of the pile end and reduce the pile settlement.

[0029] The above is only a preferred embodiment of the present invention and does not limit the present invention in any way. Any technician in the relevant technical field, without departing from the scope of the technical solution of the present invention, makes any form of equivalent replacement or modification to the technical solution and technical content disclosed in the present invention, which does not depart from the content of the technical solution of the present invention and still falls within the protection scope of the present invention.

Claims

1. An explosively expandable pile tip, characterized in that: Includes one-way check cap, flexible bladder and steel stake tip; The one-way check valve comprises a valve plate and a support plate, and the valve plate is mounted on the middle part of the support plate through an elastic reset mechanism; The support plate is fixed to the grouting port on the top of the flexible bag, and the bottom of the flexible bag is fixed to the tip of the steel pile; the middle part of the valve plate is raised, and the raised part is filled with explosive expansion material toward one side of the flexible bag.

2. The explosively expandable pile tip according to claim 1, characterized in that: The elastic reset mechanism is an elastic arm, one end of which is fixed on the support plate, and the other end of which is fixed on the valve plate.

3. The explosively expandable pile tip according to claim 1, characterized in that: The support plate is an annular steel plate, and the valve plate is a circular steel plate. After the valve plate is placed in the middle of the support plate, a certain gap is reserved between the side edge of the valve plate and the inner wall of the support plate.

4. The explosively expandable pile tip according to claim 1, characterized in that: The steel pile tip comprises a base plate and a cross-shaped pile tip located at the bottom of the base plate; The bottom of the flexible bag is fixedly connected to the bottom plate.

5. The explosively expandable pile tip according to claim 4, characterized in that: The support plate is provided with a circle of legs on one side facing the tip of the steel pile. Before the explosion, the legs are supported on the surface of the bottom plate. An oblique side plate is provided between the legs to form a space for accommodating the flexible bag in a folded state.

6. The explosively expandable pile tip according to claim 1, characterized in that: The upper surface of the one-way check cover is welded and fixed to the bottom of the prefabricated hollow steel pile.

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