Precast pile rotary excavating device and precast pile rotary excavating kit

Abstract

The utility model belongs to the technical field of pile foundation construction, and particularly relates to a precast pile rotary excavating device and a precast pile rotary excavating suite, the precast pile rotary excavating device comprises a combined rod, one side end part of the combined rod is provided with a telescopic assembly capable of extending along a direction vertical to the radial direction of the combined rod; a tool bit assembly used for rotary excavating is arranged at the end, away from the combined rod, of the telescopic assembly. The rotary excavating device is divided into a plurality of units by splitting the combined rod, so that the rotary excavating device can be conveniently conveyed to the bottom end of a precast pile. Through cooperation of the combined rod and the telescopic assembly, the rotary excavating device is conveyed to the bottom end of the precast pile on the premise that the precast pile is not moved, and the rotary excavating range can cover the bottom of the precast pile, so that boulders blocking the precast pile can be crushed, extrusion of a surrounding soil layer to the precast pile during sinking can be reduced, and the effect of protecting the precast pile is achieved. The prefabricated pile obstacle clearing process is safe and normalized, the overall construction efficiency is improved, and application and popularization in practice are facilitated.

Description

TECHNICAL FIELD

[0001] The utility model belongs to pile foundation construction technical field, concretely relates to a prefabricated pile rotary digging device and prefabricated pile rotary digging kit. BACKGROUND

[0002] Pile foundation is a common foundation form in building engineering, mainly used for transmitting the load of upper structure to deep soil or rock layer to obtain sufficient supporting force and stability, and it has extremely wide application as an important foundation construction technology. No matter high-rise building, large commercial complex or industrial plant and other types of building projects, pile foundation construction plays an indispensable role. According to the construction method, pile foundation is mainly divided into cast-in-place pile and prefabricated pile. Prefabricated pile is prefabricated in factory or construction site, and then is driven into soil by pile driver; cast-in-place pile is formed by directly pouring concrete in hole after drilling. Prefabricated pile has the advantages of construction speed and controllable quality compared with cast-in-place pile, and therefore becomes the universal choice of pile foundation construction.

[0003] Traditional prefabricated pile operation mode mainly focuses on hammering pile and static pressure pile. Hammering pile uses the impact force generated by pile hammer falling to overcome the resistance of soil to pile, so that the pile body sinks into the soil. Static pressure pile uses the weight of static pressure pile machine and counterweight to press the pipe pile into the soil by static force. In actual construction, some complex areas that are not explored due to insufficient exploration work are often encountered, and the most common one is the existence of boulders at the target position. For cast-in-place pile, the boulder can be broken in advance because the hole is drilled at the target position in advance. However, for prefabricated pile construction, when the pipe pile encounters boulders during sinking, the end of the pipe pile will bear a huge concentrated stress. This sudden high-strength stress far exceeds the range that the end of the pipe pile can bear in normal design, which may cause the concrete at the end of the pipe pile to break and the steel to deform, seriously damaging the structural integrity of the pipe pile, and further affecting the bearing capacity and stability of the entire pile foundation.

[0004] Generally speaking, when prefabricated pile encounters boulders in soil layer, the construction will be stopped and the prefabricated pile will be lifted out, and then the boulders will be broken or the site will be selected again. After lifting the pile, the soil layer in the hole needs to be reinforced to prevent soil collapse, so any solution will seriously affect the construction period. To solve this problem, a prefabricated pile tip as described in patent CN202420237332.0 is provided, which installs a tip mechanism at the bottom end of the prefabricated pile. By setting a special structure of the tip, the advantages of cross tip and conical tip are combined to form a conical cross tip shape, so that the pile sinking operation can continue when the prefabricated pile encounters boulders, thereby breaking the boulders. However, this technical solution improves the stone breaking capacity of the prefabricated pile, but the main stress of stone breaking is still borne by the prefabricated pile body. When the pile sinking pressure is too large, the prefabricated pile still has the above risks. Utility Model Content

[0005] This invention aims to overcome the shortcomings of existing technologies where continued driving of precast piles can easily cause cracks or ruptures in the pile body when obstacles are encountered during the pile driving process, and relocation or pile lifting and obstacle removal can seriously delay the construction period. It provides a precast pile rotary drilling device and a precast pile rotary drilling kit to overcome the above-mentioned shortcomings.

[0006] To achieve the above objectives, this utility model is implemented through the following technical solution:

[0007] A precast pile rotary drilling device, comprising:

[0008] A composite rod, wherein one end of the composite rod is provided with a telescopic component that can extend in a direction perpendicular to the radial direction of the composite rod;

[0009] The telescopic assembly is provided with a cutter head assembly for rotary drilling at the end away from the combined rod.

[0010] In traditional precast pile construction, it is difficult to directly break boulders when the precast pile encounters them. This is mainly because the precast pile is a hollow tube; its design strength may not be sufficient to break the boulder, and the tube wall restricts the movement, making it difficult for large drill bits to reach the bottom of the pile. Using small drill bits, it's difficult to completely clear the boulders within the tube wall area. Therefore, the combined rod in this rotary drilling device is used to transport the cutter head assembly and telescopic assembly from inside the precast tube to its end. The cutter head assembly expands the drilling range, covering the entire bottom of the precast tube, thus protecting the precast pile. The telescopic assembly pushes the cutter head assembly to a suitable position, allowing it to reach the outside of the precast pile. The telescopic device can be a telescopic rod, hydraulic rod, electric push rod, etc. Then, rotary drilling is performed to break the boulders along the precast pile's sinking path.

[0011] Furthermore, when using pipe piles for tower crane construction, the piles are often located close to the engineering piles, causing the surrounding soil to influence each other when compressed. As the precast piles continue to sink, the displacement and stress changes in the soil cause mutual compression between the tower crane piles and the engineering piles. This mutual compression applies additional lateral forces to the precast piles, altering their stress state and potentially causing them to tilt, bend, or even crack in the completed sections. If these situations occur, relocation of the pipe piles is necessary to ensure the safety and stability of the entire foundation structure, increasing construction costs and time. Therefore, to avoid soil squeezing when the precast piles sink to a deeper location, the rotary drilling device of this invention can be used. By rotary drilling the soil layer below the precast piles, the pressure required for the piles to sink is reduced, thereby reducing soil compression and preventing the aforementioned situations.

[0012] As preferred, the combination rod is spliced by two or more split rods which can be clamped with each other, and each split rod is connected with a cutter head assembly through a telescopic assembly. Due to the limitation of the inner diameter of the precast pile, if all cutter head assemblies are directly transported to the bottom end of the precast pile through a long rod, the thickness and size of the cutter head assembly will be severely limited, which will have a great impact on the excavation strength. In addition, even if the cutter head assembly adopts a telescopic design, since the cutter heads are located on the same plane, simultaneous contraction will cause adjacent cutter heads to interfere with each other, eventually leading to the volume of the rotary digging assembly being too large to pass through the precast pile. Therefore, the rotary digging device is divided into several units in the utility model, each unit includes a split rod, a telescopic assembly, and a cutter head assembly. When in use, the units are lowered one by one to avoid interference between the cutter heads. After all the cutter heads reach the bottom end of the precast pile, the split rods are combined into one to realize the combination of the rotary digging device.

[0013] As further preferred, the cutter head assembly includes a hollow cutter head and two or more telescopic cutter heads embedded in the hollow cutter head. Even if the telescopic assembly pushes the cutter heads to the outside of the precast pile, most of the precast pile is not covered by the cutter heads. After the rotary digging device starts working, under high-speed rotation, gravel may pass through the cutter heads and hit the precast pile, which can easily cause damage to the precast pile. Therefore, the utility model designs an unfolding structure in the cutter head part to achieve the effect of completely covering the end of the precast pile with the cutter head. In practice, considering the strength of the cutter head and the reduction of the volume, two telescopic cutter heads are preferably slidingly arranged in the hollow cutter head. The two telescopic cutter heads are closely attached to the hollow cutter head. When pressure is applied between the telescopic cutter heads, the two cutter heads can be ejected to both sides.

[0014] As further preferred, a cavity is provided between the adjacent telescopic cutter heads in the hollow cutter head, and the rotary digging device further includes a pressurizing assembly capable of applying pressure in the cavity to drive the telescopic cutter heads to pop out. Since the cutter head assembly needs to go down to the soil layer, the pressure of the soil layer on the cutter head increases with the depth. A high-power ejection device is needed to eject the telescopic cutter head. In practice, hydraulic or pneumatic methods can be used. A notch is pre-cut at the corresponding position between the adjacent telescopic cutter heads, so that when the adjacent telescopic cutter heads are closely attached, a cavity is formed. A hydraulic pipe or air pressure pipe is connected to the hollow cutter head at the corresponding cavity. When air pressure or hydraulic pressure is transmitted to the cavity, a large force is provided to the telescopic cutter heads on both sides to eject them.

[0015] As further preferred, the combination rod is internally provided with a reserved channel capable of allowing the pressurizing assembly to pass through. Whether it is hydraulic or pneumatic, in order to ensure the strength of the pressure, the pressure generating device is preferably arranged above the ground, so a reserved channel is needed to transmit the pressure to one end of the cutter head assembly through a conveying pipe.

[0016] As a further preferred embodiment, the splitting rod is provided with a reserved groove, which, when the splitting rods are assembled, interlocks with each other to form a reserved channel that allows the pressurizing component to pass through. When using a splitting rod design, to ensure the strength of the splitting rod, it is best to design the reserved channel at the center of the assembled splitting rod. An arc-shaped reserved groove can be opened on the side of the splitting rod near the center, thereby forming a circular reserved channel after the splitting rods are assembled.

[0017] As a further preferred embodiment, the pressurization assembly includes a pressure delivery pipe that is connected to the cutter head assembly via a reserved channel.

[0018] As a further preferred embodiment, the telescopic assembly has a passageway capable of accommodating the pressure delivery pipe, so that the pressure delivery pipe is embedded within the telescopic assembly and connected to the hollow cutter head. To prevent the exposed pressure delivery pipe from being damaged by debris such as gravel, the pressure delivery pipe can be embedded within the telescopic assembly.

[0019] Preferably, the telescopic cutter head includes a first telescopic cutter head and a second telescopic cutter head. The end of the first telescopic cutter head is provided with a locking tooth, and the end of the second telescopic cutter head is provided with a locking groove. Adjacent telescopic cutter heads outside the hollow cutter head are engaged with each other through the locking tooth and the locking groove. Regardless of whether a split rod design is used, due to the telescopic design of the cutter head, on the one hand, the assembly of the cutter heads is at the lower end of the precast pipe, making it difficult to visually observe whether the cutter heads have been assembled; on the other hand, the gap between two adjacent telescopic cutter heads affects the overall strength of the rotary drilling rig. Therefore, after the telescopic cutter heads are deployed, a locking structure is provided between adjacent telescopic cutter heads. In practice, all telescopic cutter heads are arranged sequentially, so that the locking teeth and locking grooves of the cutter heads after full deployment are sequentially engaged, thereby improving the overall strength of the rotary drilling rig.

[0020] On the other hand, this utility model also discloses a precast pile rotary drilling kit, including the aforementioned precast pile rotary drilling device, and a cleaning drill bit for cleaning debris inside the precast pile. The cleaning drill bit is a device for cleaning debris inside the pipe pile. When pile driving is hindered, the cleaning drill bit is first used to clean the impurities inside the pipe pile, and then the aforementioned rotary drilling device is transported to the pile end.

[0021] Therefore, this utility model has the following beneficial effects:

[0022] (1) This utility model uses the combination of the combined rod and the telescopic component to transport the rotary drilling device to the bottom of the precast pile without moving the precast pile, and ensures that the rotary drilling range can cover the precast pile. Therefore, it can not only break the isolated rocks that obstruct the precast pile, but also reduce the pressure of the soil layer on the precast pile when sinking, thus playing the role of protecting the precast pile.

[0023] (2) The present invention divides the rotary drilling device into several units through the combination rod design of the preferred scheme. While increasing the thickness and size of the cutter head, it avoids mutual interference between the cutter heads and facilitates the lowering of the rotary drilling device.

[0024] (3) By using the preferred solution of the cleaning drill bit, this utility model makes the entire precast pile clearing process smoother, transforming the originally complex, time-consuming and dangerous construction plan into a safe and routine construction process, improving the overall construction efficiency, effectively reducing construction time and cost, and is conducive to its promotion and application in production practice. Attached Figure Description

[0025] Figure 1 This is a schematic diagram of the rotary drilling device and the cleaning drill bit of this utility model.

[0026] Figure 2 This is a schematic diagram of the rotary drilling device of this utility model in its retracted state.

[0027] Figure 3 This is a schematic diagram of the rotary drilling device of this utility model in its extended state.

[0028] Figure 4 This is a schematic diagram of the cutter head ejection of the rotary drilling device of this utility model.

[0029] Figure 5 This is a structural schematic diagram of a single splitting rod and cutter head assembly of the rotary drilling device of this utility model.

[0030] Figure 6 This is a flowchart illustrating the construction process using the new rotary drilling kit.

[0031] In the diagram: 1. Combination rod; 2. Reserved channel; 3. Splitting rod; 4. Reserved slot; 5. Cleaning drill bit; 10. Cutter head assembly; 11. Hollow cutter head; 12. Telescopic cutter head; 13. Cavity; 20. Telescopic assembly; 30. Pressurization assembly; 31. Pressure delivery pipe; 121. First telescopic cutter head; 122. Second telescopic cutter head; 123. Clamping tooth; 124. Detailed Implementation

[0032] The present invention will be further described below with reference to the accompanying drawings and specific embodiments. Those skilled in the art will be able to implement the present invention based on these descriptions. Furthermore, the embodiments of the present invention described below are generally only a part of the embodiments of the present invention, and not all of the embodiments. Therefore, all other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort should fall within the scope of protection of the present invention.

[0033] Example 1

[0034] likeFigure 1 As shown, the rotary drilling kit of this embodiment includes a cleaning drill bit 5 and a rotary drilling device. The rotary drilling device consists of a combined rod 1, four telescopic components 20, and four cutter head assemblies 10. The bottom end of the combined rod 1 is welded with four telescopic components 20 in a cross shape, so that the telescopic components 20 can extend and retract in a radial direction perpendicular to the combined rod 1. Each telescopic component 20 has a cutter head assembly 10 for rotary drilling welded to its end away from the combined rod 1. The telescopic components 20 are hydraulic rods.

[0035] The implementation method of this embodiment is as follows:

[0036] When the precast pile cannot be driven any further and rotary drilling is required to remove the obstacles below, first use the cleaning drill bit 5 to clean the inside of the precast pile to facilitate the lowering of the rotary drilling device. Keep the rotary drilling device in the retracted state, and transport the cutter head assembly 10 and the telescopic assembly 20 from inside the precast pipe to the outside of the end via the combination rod 1. Push the cutter head assembly 10 outwards via the hydraulic rod of the telescopic assembly 20 until it reaches the outside of the precast pile. Slightly pull up the combination rod 1 to ensure that the rotary drilling range is greater than the bottom end of the precast pile, and start the rotary drilling device to perform rotary drilling.

[0037] Example 2

[0038] like Figures 2-6As shown, a rotary drilling kit in this embodiment includes a debris-removing drill bit 5 and a combined rotary drilling device. Through a disassembly and reassembly design, a larger cutter head can be used. The combined rotary drilling device consists of four rotary drilling units. Each unit includes a disassembly rod 3 for conveying and supporting, a cutter head assembly 10 for rotary drilling, and a telescopic assembly 20 for extending the cutter head assembly 10. This telescopic assembly is an electric push rod. The contact surfaces of adjacent disassembly rods 3 are provided with protrusions and grooves, allowing the disassembly rods 3 to interlock. The cross-section of each disassembly rod 3 is a quarter-circle surface, with a pre-drilled groove 4 at the apex, so that a circular pre-drilled channel 2 is formed at the center after the four rotary drilling units are combined. A hollow telescopic component 20 is welded to the arc surface at the end of the splitting rod 3. A hollow cutter head 11 is welded to the other end of the telescopic component 20, so that the reserved channel 2, the hollow part of the telescopic component 20, and the hollow cutter head 11 can form a complete passage for the pressurizing component 30 to pass through. The pressurizing component is a hydraulic device, the main body of which is set on the ground, and a pressure transmission pipe 31 is led out and passes through the above-mentioned passage. Two telescopic cutter heads 12 are embedded in the hollow cutter head 11, and the three fit together tightly and allow relative sliding. A rectangular notch is provided on the side where the two telescopic cutter heads 12 fit together, thereby forming a rectangular cavity 13 at the fitting point. The pressure transmission pipe 31 is connected to the cavity 13, so that hydraulic pressure can be transmitted into the cavity 13. In addition, taking a cutter head assembly 10 as an example, the hollow cutter head 11 includes a first telescopic cutter head 121 and a second telescopic cutter head 122. The end of the first telescopic cutter head 121 is provided with a locking tooth 123, and the end of the second telescopic cutter head 122 is provided with a locking groove 124. When the telescopic cutter head 12 pops out, the telescopic cutter heads 12 of the adjacent rotary drilling unit can be engaged with each other through the locking tooth 123 and the locking groove 124.

[0039] The usage process of this embodiment is as follows:

[0040] like Figures 1-6 As shown, when the precast pile cannot be driven any further and rotary drilling is required to remove the obstacles below, the interior of the precast pile is first cleaned using the cleaning drill bit 5 to facilitate the lowering of the rotary drilling device. The assembly process of the rotary drilling device is as follows: Figure 6 As shown, to avoid interference between the cutter head assemblies 10, the splitting rod 3 drives the cutter head assemblies 10 and the pressure conveying pipe 31 to be inserted into the precast pile one by one. After all the cutter head assemblies 10 reach the bottom of the precast pile, the electric push rod of the telescopic assembly 20 is activated, causing the telescopic assembly 20 to push the cutter head assemblies 10 outward, achieving the desired effect. Figure 3As shown, the hollow cutter head 11 should be slightly pulled up on the outside of the precast pile wall, ensuring that the rotary drilling device completely covers the entire precast pile. Then, extend another splitting rod 3 and repeat the above steps until all cutter head assemblies 10 reach the bottom of the precast pile. Use the protruding grooves on the side of the splitting rod 3 to connect the splitting rods 3 into one piece. Turn on the hydraulic pump to transmit hydraulic pressure to the cavity 13. Under the action of the hydraulic pressure, the telescopic cutter head 12 pops out from the hollow cutter head 11. The popped telescopic cutter head 12 engages with the telescopic cutter head 12 of another rotary drilling unit through the side teeth 123 and grooves 124, achieving the desired effect. Figure 4 Once the entire rotary drilling rig is assembled, it is then turned on to begin rotary drilling.

Claims

1. A precast pile rotary drilling device, characterized in that: The assembly includes a combination rod (1), one end of which is provided with a telescopic component (20) that can extend in a radial direction perpendicular to the combination rod (1), and the end of the telescopic component (20) away from the combination rod (1) is provided with a cutter head assembly (10) for rotary drilling.

2. The precast pile rotary drilling device according to claim 1, characterized in that: The combined rod (1) is composed of two or more interlocking split rods (3), and each split rod (3) is connected to a blade assembly (10) via a telescopic component (20).

3. The precast pile rotary drilling device according to claim 2, characterized in that: The cutter head assembly (10) includes a hollow cutter head (11) and two or more telescopic cutter heads (12) embedded in the hollow cutter head (11).

4. A precast pile rotary drilling device according to claim 3, characterized in that: The hollow cutter head (11) has a cavity (13) between adjacent telescopic cutter heads (12), and the rotary drilling device also includes a pressurizing component (30) that can apply pressure in the cavity (13) to drive the telescopic cutter head (12) to pop out.

5. A precast pile rotary drilling device according to claim 4, characterized in that: The combined rod (1) has a reserved channel (2) inside that allows the pressurization component (30) to pass through.

6. A precast pile rotary drilling device according to claim 5, characterized in that: The splitting rod (3) is provided with a reserved slot (4), so that the reserved slots (4) are spliced ​​together after the splitting rod (3) is assembled to form a reserved channel (2) that allows the pressurizing component (30) to pass through.

7. A precast pile rotary drilling device according to claim 5 or 6, characterized in that: The pressurization assembly (30) includes a pressure delivery pipe (31) connected to the cutter head assembly (10) via a reserved channel (2).

8. A precast pile rotary drilling device according to claim 7, characterized in that: The telescopic assembly (20) has a passage that can accommodate the pressure delivery pipe (31), so that the pressure delivery pipe (31) is embedded in the telescopic assembly (20) and connected to the hollow cutter head (11).

9. A precast pile rotary drilling device according to claim 3, characterized in that: The telescopic cutter head (12) includes a first telescopic cutter head (121) and a second telescopic cutter head (122). The end of the first telescopic cutter head (121) is provided with a locking tooth (123), and the end of the second telescopic cutter head (122) is provided with a locking groove (124). The telescopic cutter heads (12) adjacent to the hollow cutter head (11) are engaged with each other by the locking tooth (123) and the locking groove (124).

10. A precast pile rotary drilling kit, characterized in that: The precast pile rotary drilling device includes any one of claims 1-9, and further includes a cleaning drill bit (5) for cleaning debris inside the precast pile.

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