A self-drilling hole-forming expansion head anchor rod

Abstract

The application discloses a self-drilling hole-forming enlarged-head anchor rod, which comprises, from the first end to the tail end, an enlarged-head section, an anchoring section, a free section and an anchor-sealing embedding section; the anchor-sealing embedding section comprises a beam arranged on a pile foundation and a pad and an anchor head fixed to the outer side of the beam; the diameter of the enlarged-head section is 2-3 times of the diameter of the anchoring section; and the anchor rod is formed into a hole in rock and soil by using an anchor rod hole-forming device to complete hole forming and pouring. The self-drilling hole-forming enlarged-head anchor rod is not limited by a working site, is not affected by the construction sequence of traditional anchor rods and pile foundations, and has high strength and good tensile resistance.

Description

Technical Field

[0001] This invention belongs to the field of building construction technology, and in particular relates to a self-drilling enlarged head anchor bolt. Background Technology

[0002] In order to resist the pressure of soil and water in the strata, anchor bolts are often used in engineering construction. However, the quality of anchor bolt construction is difficult to control in the blind area of ​​soil and rock. The construction process of anchor bolts is complicated (including drilling, reinforcement, filling with stone, grouting, and testing), which seriously restricts the progress of the project.

[0003] Due to the difficulty in quality control and the complexity of the procedures, yet its status as a critical technical link, test pile experiments are often required before large-scale construction can commence. In the context of high-turnover real estate development and fast-paced infrastructure construction, the test pile process alone can take up to a month, significantly impacting the project's progress. Moreover, the consequences of anti-buoyancy anchor failure are extremely serious, often causing structural damage and safety accidents, which are difficult to remedy using conventional techniques. Summary of the Invention

[0004] The purpose of this invention is to overcome the problems of the prior art and disclose a self-drilling enlarged head anchor rod. The self-drilling enlarged head anchor rod of this invention is not limited by the workplace, is not affected by the traditional anchor rod and pile foundation construction sequence, and has high strength and good tensile performance.

[0005] The objective of this invention is achieved through the following technical solution:

[0006] A self-drilling enlarged head anchor rod, comprising, from the first end to the last end, an enlarged head section, an anchoring section, a free section, and a sealing and anchoring section. The sealing and anchoring section includes a beam installed on the pile foundation and a pad and an anchor head fixed to the outer side of the beam. The diameter of the enlarged head section is 2 to 3 times the diameter of the anchoring section. The anchor rod is drilled and cast in the soil using an anchor rod drilling device.

[0007] According to a preferred embodiment, the length of the anchoring section is twice the length of the enlarged head section; the length of the anchoring section is equal to the length of the free section.

[0008] According to a preferred embodiment, the anchor bolt drilling device includes: a drive rod and a drill bit, wherein the drive rod is connected to the drill rod at the end of the drill bit by a tongue and groove joint, and drives the drill bit to drill anchor bolts in the construction soil layer;

[0009] The drill bit has a drill tail fin at its rear end, which is fixed to the drill rod to achieve hole formation.

[0010] The drill bit tail fin is provided with a hole-enlarging wing plate at the rear end. The hole-enlarging wing plate is arranged around the drill rod circumferentially and is hinged to the drill rod.

[0011] The drill rod is also fitted with an expansion wing sliding ring. By pushing the expansion wing sliding ring, the expansion wing sliding ring completes the pushing of the hole-expanding wing plate, thereby expanding the hole-expanding wing plate to the hole-expanding wing plate unfolding position, and rotating to complete the hole-expanding at the end of the anchor rod.

[0012] According to a preferred embodiment, the process of drilling the end of the anchor bolt includes: when the drill bit drills to the preset anchor bolt depth, the expanding wing sliding ring is jacked up, and the expanding wing sliding ring completes the jacking of the hole-expanding wing plate, thereby expanding the hole-expanding wing plate to the expanded hole-expanding wing plate position; the drill bit rotates and retracts in the opposite direction, thereby expanding the hole at the end of the anchor bolt so that an enlarged head section can be obtained after subsequent grouting.

[0013] According to a preferred embodiment, the anchor bolt hole-forming device includes a sleeve, which pushes the expansion wing sliding ring to complete the expansion of the hole-expanding wing plate when forming a hole at the end of the anchor bolt.

[0014] According to a preferred embodiment, the sleeve is composed of several segments spliced ​​together, with an external thread structure at the beginning of each segment and an internal thread structure at the end of each segment.

[0015] According to a preferred embodiment, the sleeve has a perforated tube structure near the head end of the anchor bolt, and a solid tube structure at the tail end of the sleeve.

[0016] According to a preferred embodiment, the anchor bolt drilling device includes a grouting pipe, the end of which is provided with a vibration ring.

[0017] According to a preferred embodiment, the grouting pipe is a flexible grouting pipe body.

[0018] According to a preferred embodiment, the head of the drill bit has a sharp, petal-like structure, and the tail fin and the reaming fin have a plate-like structure.

[0019] According to a preferred embodiment, when the drill bit has a single-lobed structure, it is a 180-degree flat drill bit; when it has two lobes, it is a cross-shaped drill bit with a 90-degree angle; or it has a three-lobed structure, which is symmetrically distributed with a 120-degree angle.

[0020] According to a preferred embodiment, the first end of the drive rod is provided with a male port, and the end of the drill rod is provided with a female port. The male port and the female port are engaged, and the male port and the female port are connected through a connecting shaft. The position of the connecting shaft is locked by a snap-fit ​​component.

[0021] The aforementioned main solution of the present invention and its various further alternative solutions can be freely combined to form multiple solutions, all of which are solutions that can be adopted and are claimed by the present invention. Those skilled in the art, after understanding the solution of the present invention, will realize that there are many combinations based on existing technology and common knowledge, all of which are technical solutions to be protected by the present invention, and will not be exhaustively listed here.

[0022] The beneficial effects of this invention are as follows: The anchor bolt of this invention requires no additional equipment and is formed in one piece. The advantages of the steel casing sleeve are that it prevents hole collapse and facilitates the constraint of grout flow direction and volume, resulting in better anchor bolt columnarity, stronger compactness, stronger bond between grout and anchor bolt, and greater anchor bolt durability. The anchor bolt has stronger tensile strength. The steel casing sleeve and grouting pipe are recyclable, saving materials. Based on the cooperation of the casing and grouting pipe, grouting fluid is saved while improving grouting quality. Attached Figure Description

[0023] Figure 1 This is a schematic diagram of the structure of the self-drilling enlarged head anchor rod of the present invention;

[0024] Figure 2 This is a schematic diagram of the anchor bolt hole-forming device of the present invention;

[0025] Among them, 1-drill bit, 2-drill bit tail wing, 3-reamer wing plate, 4-reamer wing plate unfolded position, 5-connecting ring, 6-expanding wing sliding ring, 7-drill rod, 8-female end, 9-male end, 10-connecting shaft, 11-clamping piece, 12-sleeve, 12a-external thread, 12b-internal thread, 13-grouting pipe, 14-vibration ring, 15-drive rod, 20-anchor rod, 21-enlarged head section, 22-anchoring section, 23-free section, 24-pad plate, 25-anchor rod head, 30-pile foundation, 31-beam. Detailed Implementation

[0026] The following specific examples illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that, unless otherwise specified, the following embodiments and features described therein can be combined with each other.

[0027] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0028] In the description of this invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the product of this invention is in use. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this invention. In addition, the terms "first," "second," "third," etc., are only used to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0029] Furthermore, terms such as "horizontal," "vertical," and "sag" do not imply that components must be absolutely horizontal or suspended, but rather that they can be slightly tilted. For example, "horizontal" simply means that its direction is more horizontal relative to "vertical," and does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0030] In the description of this invention, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set," "install," "connect," and "link" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0031] Furthermore, it should be noted that, unless otherwise specified, the structures, connections, positions, power sources, etc. involved in this invention are all things that a person skilled in the art can know without creative effort based on the prior art.

[0032] Example 1:

[0033] refer to Figures 1 to 2 As shown, this embodiment discloses a self-drilling enlarged head anchor bolt. The anchor bolt 20 includes an enlarged head section 21, an anchoring section 22, and a free section 23, wherein the length of the anchoring section 22 is twice the length of the enlarged head section 21 and the length of the free section 23.

[0034] The diameter of the enlarged head section 21 is 2 to 3 times the diameter of the anchoring section 22. The anchor rod 20 is formed and poured in the rock and soil using an anchor rod drilling device.

[0035] Preferably, the anchor bolt drilling device includes a drive rod 15 and a drill bit 1. The drive rod 15 is connected to the drill rod 7 at the end of the drill bit 1 by a tongue and groove joint, and drives the drill bit 1 to drill the anchor bolt 20 in the soil and rock layer.

[0036] Preferably, the drill bit 1 has a tail fin at its rear end, and the tail fin is fixed to the drill rod 7 to achieve hole formation.

[0037] Preferably, the drill bit 1 has a reaming wing plate 3 at its rear end, which is arranged circumferentially around the drill rod 7 and hinged to the drill rod 7. Specifically, the reaming wing plate 3 is hinged to the drill rod 7 via a connecting ring 5.

[0038] Preferably, the drill rod 7 is also fitted with an expansion wing sliding ring 6. By pushing the expansion wing sliding ring 6, the expansion wing sliding ring 6 completes the pushing of the hole-expanding wing plate 3, thereby expanding the hole-expanding wing plate 3 to the hole-expanding wing plate unfolding position 4, and rotating to complete the hole-expanding at the end of the anchor rod 20.

[0039] Preferably, the anchor bolt hole-forming device includes a sleeve 12. When forming a hole at the end of the anchor bolt 20, the sleeve 12 pushes the expansion wing sliding ring 6 to complete the unfolding of the hole-expanding wing plate 3.

[0040] Preferably, the sleeve 12 is composed of several segments spliced ​​together, with an external thread structure 12a at the beginning of each segment and an internal thread structure 12b at the end of each segment, thereby realizing the connection between the beginning and end of each segment.

[0041] Furthermore, the steel casing 12 is equipped with a reducer, the reducer having an external thread structure 12a and the increaser having an internal thread structure 12b, and the front and rear sections of the steel casing are connected by threading.

[0042] The steel casing sleeve 12 comes in two specifications: specification 1 has quincunx-shaped holes and is called a perforated pipe, while specification 2 is a solid-walled pipe. The steel casing sleeve also serves as a grouting protection guide pipe.

[0043] Preferably, the sleeve 12 near the head end of the anchor rod 20 has a perforated tube structure, and the tail end of the sleeve 12 has a solid tube structure.

[0044] Preferably, the anchor bolt drilling device includes a grouting pipe 13, and a vibration ring 14 is provided at the end of the grouting pipe 13. Further, the grouting pipe 13 is a flexible grouting pipe body.

[0045] Specifically, the vibration of the vibrating ring 14 enables the grouting pipe 13 to move in and out of the casing and enlarged head section, and also prevents the grout outlet from becoming blocked under the action of vibration. The grout can be a mixed grout with added retarder, water-reducing agent and waterproofing agent. This ensures the grouting quality, prevents the anchor rod from being corroded and improves the durability of the anchor rod.

[0046] Preferably, the drill bit 1 drill bit assembly can be configured with single or multiple petals according to the properties of the rock and soil, and the tail fin and the reaming wing plate 3 of the drill bit 1 are plate-shaped structures.

[0047] Furthermore, when the drill bit 1 has a single-lobed structure, it is a 180-degree flat drill bit 1; when it has two lobes, it is a cross-shaped drill bit with a 90-degree angle; or a three-lobed structure, which is symmetrically distributed with a 120-degree angle.

[0048] Preferably, the drive rod 15 has a male port 9 at its head and the drill rod 7 has a female port 8 at its end. The male port 9 and the female port 8 are engaged, and the male port 9 and the female port 8 pass through each other via a connecting shaft 10. The position of the connecting shaft 10 is locked by a locking member 11. This enables the transmission of horizontal tension and compression as well as rotational torque.

[0049] Preferably, the process of drilling the end of the anchor rod includes: when the drill bit 1 drills to the preset depth of the anchor rod 20, the expanding wing sliding ring 6 is pushed to complete the pushing of the hole-expanding wing plate 3, thereby expanding the hole-expanding wing plate 3 to the expanded position; the drill bit 1 rotates and retracts in the opposite direction, thereby expanding the hole at the end of the anchor rod 20 so that the enlarged head section 21 can be obtained after subsequent grouting.

[0050] Specifically, when the alloy drill bit 1 is drilled to the designed depth, the diameter of the hole is the end diameter d of the drill bit tail wing 2. The outer diameter of the casing 12 is smaller than d. The casing 12 can be pressed in or rotated in, which serves to prevent hole collapse and protect the anchor rod body. During anchor rod drilling, the reaming wing plate 3 is in a relaxed state. When the designed depth is reached, the casing 12 is pressed, which in turn squeezes the expansion wing sliding ring 6, causing the reaming wing plate 4 to expand. The wing plate opens, and the anchor rod body rotates while retracting in the opposite direction, thereby achieving hole expansion. Assuming the total anchor rod length is L, the casing 10 is divided into two parts: the deep end is half the length of the perforated tube (L / 2), and the shallow end is half the length of the solid tube (L / 2).

[0051] When drill bit 1 reaches the bottom of the enlarged section, the anchor rod rotates back by L / 4. During the return stroke, casing 12 follows anchor rod 1, and grouting pipe 13 injects grout to ensure the grout fully integrates with the soil and rock. This process repeats several times based on test data. The anchor rod body is then driven back into the bottom of the designed enlarged head. The steel casing 12 continues to inject grout between the enlarged section 21 and the anchoring section 22 to ensure the strength of the enlarged head. At this point, L / 4 of the steel casing 12 has been extracted from the soil and rock layer. What remains in the soil and rock layer are L / 2 of the perforated pipe (located in the anchoring section 22) and L / 4 of the solid pipe (in the free section 23). Grouting continues to squeeze out the soil inside the steel casing. Grouting stops when clean cement grout flows out.

[0052] The anchor body is perpendicular to the stress surface of the anchoring and embedding section for better stress distribution. The anchoring and embedding section includes a cap beam (at the top of the support pile 30), a waist beam (in the middle of the support pile 30), a bottom beam (at the bottom of the support pile 30), an anchor plate 24, and an anchor head 25. The anchor plate 24 and the anchor head 25 must have sufficient strength, as stress concentration is significant at this location.

[0053] This anchor can serve as a support anchor structure or an underground anti-buoyancy structure. When used as an underground anti-buoyancy structure, the support pile 30 becomes a horizontal restraint member such as a water-resistant slab or ground beam. The entire anchor area is divided into two parts: the free face and the soil / rock layer. Self-drilling anchors utilize the friction between the enlarged head and the anchoring section and the soil / rock to achieve the anchor's pull-out force. When used as a horizontal support anchor, the angle between the anchor and the horizontal plane should be 8-15 degrees downwards. When used as an anti-buoyancy anchor, it should be perpendicular to the anti-buoyancy slab or ground beam.

[0054] The anchor bolt installation process of this invention requires no additional equipment and is completed in one step. The advantages of the steel casing sleeve are that it prevents borehole collapse and facilitates the control of grout flow direction and volume, resulting in better anchor bolt columnarity, stronger compactness, stronger grout-anchor bolt bond, and greater anchor bolt durability. The anchor bolt also exhibits stronger tensile strength. Furthermore, the steel casing sleeve and grouting pipe are recyclable, saving materials. Based on the combination of the casing and grouting pipe, grouting fluid is saved while improving grouting quality.

[0055] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for constructing a self-drilling, enlarged-head anchor bolt, characterized in that, The anchor rod (20) includes, from the first end to the last end, an enlarged head section (21), an anchoring section (22), a free section (23) and a sealing and anchoring section. The sealing and anchoring section includes a beam (31) installed on the pile foundation (30) and a pad (24) and an anchor head (25) fixed to the outside of the beam (31). The diameter of the enlarged head section (21) is 2 to 3 times the diameter of the anchoring section (22), and the anchor rod (20) is formed and poured in the rock and soil using an anchor rod drilling device; The anchor bolt drilling device includes a drive rod (15) and a drill bit (1). The drive rod (15) and the drill rod (7) at the end of the drill bit (1) are connected by a tongue and groove joint, and the drill bit (1) is driven to form an anchor bolt hole in the construction soil layer. The drill bit (1) has a drill tail wing (2) at its rear end. The drill tail wing (2) is fixed on the drill rod (7) and is used to achieve the hole-forming function. The drill bit tail wing (2) is provided with a hole-expanding wing plate (3) at the rear end. The hole-expanding wing plate (3) is arranged around the drill rod (7) in a circumferential direction and is hinged to the drill rod (7). The drill rod (7) is also fitted with a wing sliding ring (6). By pushing the wing sliding ring (6), the wing sliding ring (6) completes the pushing of the hole-expanding wing plate (3), thereby expanding the hole-expanding wing plate (3) to the hole-expanding wing plate unfolding position (4), and rotating to complete the hole expansion at the end of the anchor rod. The process of drilling holes at the ends of anchor bolts includes: When the drill bit (1) drills to the preset anchor depth, the expanding wing sliding ring (6) is pushed to complete the pushing of the expanding wing plate (3), thereby expanding the expanding wing plate (3) to the expanding wing plate unfolding position (4). The drill bit (1) rotates and retracts in the opposite direction, thereby enlarging the hole at the end of the anchor rod so that an enlarged head section can be obtained after subsequent grouting; The anchor bolt hole-forming device includes a sleeve (12). When forming a hole at the end of the anchor bolt, the sleeve (12) pushes the expansion wing sliding ring (6) to complete the unfolding of the hole-expanding wing plate (3). The sleeve (12) is composed of several segments spliced ​​together. The first end of each segment is provided with an external thread structure (12a), and the end of each segment is provided with an internal thread structure (12b). The sleeve (12) near the first end of the anchor rod is a perforated tube structure, and the tail end of the sleeve (12) is a solid tube structure. The anchor bolt drilling device includes a grouting pipe (13), and a vibration ring (14) is provided at the end of the grouting pipe (13). The head of the drill bit (1) has a sharp, petal-like structure, and the tail fin (2) and the reaming fin (3) of the drill bit have a sheet-like structure. The drive rod (15) has a male port (9) at its head end and a female port (8) at its end. The male port (9) and the female port (8) are engaged. The male port and the female port (8) are connected through the connecting shaft (10), and the position of the connecting shaft (10) is locked through the snap-fit ​​part (11).

2. The construction method for self-drilling enlarged head anchor bolts as described in claim 1, characterized in that, The length of the anchoring section (22) is twice the length of the enlarged head section (21); the length of the anchoring section (22) is equal to the length of the free section (23).

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