Drill bit, drilling tool, reinforcement device and method for collapsible loess foundation reinforcement

Abstract

The present invention belongs to the field of building foundation treatment, and specifically discloses a drill bit, a drilling tool, a reinforcement device and a method for reinforcing a collapsible loess foundation. The reinforcement device includes a drilling tool and a gas delivery unit; the drill bit of the drilling tool includes a connecting member, a deformable cover, a driving component and a plurality of nozzles connected to the outer side of the deformable cover surface; the cover surface of the deformable cover can be deformed under the drive of the driving component; when the cover surface of the deformable cover is deformed into an arc-shaped convex surface, the spraying directions of the plurality of nozzles are divergent; when the cover surface of the deformable cover is deformed into an arc-shaped concave surface, the spraying directions of the plurality of nozzles are convergent. The method cuts the soil by spraying a high-pressure airflow downwardly and divergently; forms a high-pressure airflow cover by spraying a high-pressure airflow downwardly and convergently to compact the soil, thereby achieving the reinforcement of the collapsible loess foundation; the reinforcement effect of this method is good, the soil can reach a higher density, and the drill rod does not need to vibrate in this scheme, thereby avoiding noise pollution.

Description

Technical Field

[0001] The invention belongs to the technical field of building foundation treatment, and more specifically, relates to a drill bit, a drilling tool, a reinforcement device and a method for reinforcing a collapsible loess foundation. Background Art

[0002] At present, the main methods for dealing with collapsible loess foundations in the industry are replacement method, dynamic tamping method, compaction pile method and CFG pile method. With the development of the industry, a new method for dealing with collapsible loess foundations has been proposed: the vibration rod compaction method.

[0003] The vibration rod compaction method does not require additional fillers during construction, and the construction is simple and environmentally friendly. However, due to the low water content, low compressibility and high strength of collapsible loess foundations, the vibration rods are often unable to sink; for areas where it can be implemented, due to the difficulty in destroying the soil structure of the loess foundation, the sinking speed is slow, the energy diffusion (reinforcement effect) is poor, the construction efficiency is low, and the reinforcement effect is poor.

[0004] The patent document with application number 202010470675.8 discloses a method for reinforcing collapsible loess foundations. The method uses a vibrating rod to vibrate at a preset vibration frequency, and at the same time turns on the high-pressure airflow injection so that the high-pressure airflow cuts the soil, destroys the soil structure, and improves the efficiency of sinking the rod; after the vibrating rod sinks to a preset depth, the high-pressure airflow injection is turned off, and the vibration of the vibrating rod is maintained to compact and reinforce the loess foundation. This solution solves the problem of difficulty in sinking the rod and low efficiency during construction when the traditional vibrating rod compaction method is applied to the reinforcement of collapsible loess foundations.

[0005] However, further research has shown that the above-mentioned prior art still has the following defects or shortcomings: First, this technical solution relies on the deadweight of the soil and the vibration of the vibration rod to reinforce the soil during the process of reinforcing the soil. That is, after the vibration rod reaches the preset depth, the gas assist is turned off and the vibration rod is kept vibrating to reinforce the soil. This method has limited reinforcement effect and is difficult to achieve the corresponding density for sites with high compaction requirements. Secondly, the vibration rod generates greater noise and vibration during the vibration process, causing noise pollution.

[0006] Based on the above-mentioned defects and shortcomings, this field urgently needs to further improve the design of the reinforcement device and method for collapsible loess foundation, so as to solve the problems of limited reinforcement effect of the vibration rod compaction method in the existing technology and difficulty in achieving a high density, as well as the problem of noise and vibration generated by vibration of the vibration rod. Summary of the invention

[0007] In view of the above defects or improvement needs of the prior art, the present invention provides a drill bit for reinforcing collapsible loess foundation, a drilling tool provided with the drill bit, a reinforcement device including the drill tool, and a method for reinforcing the collapsible loess foundation using the reinforcement device, which can effectively solve the problems in the prior art that the vibration rod compaction method has limited reinforcement effect and is difficult to achieve a high density, and at the same time solve the problem of noise and vibration generated by vibration of the vibration rod.

[0008] To achieve the above-mentioned purpose, according to one aspect of the present invention, a drill bit is provided, the drill bit comprising a connecting member, a deformable cover, a driving component and a plurality of nozzles; the rear end of the connecting member is used to be connected to the drill rod, the front end is connected to the deformable cover and the two are surrounded by a cavity, and a gas passage running through the front and rear ends is formed inside the connecting member; the driving component is located in the cavity, and one end of the driving component is connected to the connecting member, and the other end is connected to the inner side of the cover surface of the deformable cover, and the driving component is used to drive the cover surface of the deformable cover to deform; the plurality of nozzles are installed on the outer side of the cover surface of the deformable cover;

[0009] The cover surface of the deformable cover can be deformed into an arc-shaped convex surface under the drive of the driving component, so that the multiple nozzles face forward and diverge along the arc-shaped convex surface. The cover surface of the deformable cover can also be deformed into an arc-shaped concave surface under the drive of the driving component, so that the multiple nozzles face forward and converge along the arc-shaped concave surface.

[0010] During operation, when the drill bit sinks to penetrate into the collapsible loess foundation, the driving component drives the cover surface of the deformable hood to deform into an arc-shaped convex surface, and multiple nozzles spray high-pressure airflow downward in a divergent manner to cut the soil. The high-pressure airflow cuts and breaks the soil structure to form loose particles, thereby destroying the collapsible loess structure; when the drill bit is lifted to extract the loess foundation, the driving component drives the cover surface of the deformable hood to deform into an arc-shaped concave surface, and multiple nozzles spray high-pressure airflow downward in a convergent manner to form a high-pressure airflow hood. The high-pressure airflow hood compacts the soil to achieve reinforcement of the collapsible loess foundation.

[0011] Through the above conception, on the one hand, the cutting and reinforcement of the soil is achieved by changing the spray direction of the high-pressure airflow. This method has a good reinforcement effect and the soil can achieve a higher density. On the other hand, in this scheme, the drill bit only needs to sink or rise, avoiding the use of vibration to reinforce the soil and generate large noise or vibration, thereby avoiding noise pollution.

[0012] According to another aspect of the present invention, a drilling tool is proposed, which includes the drill bit and a drill rod with a hollow structure inside, the front end of the drill rod is connected to the rear end of the connecting member of the drill bit, and the hollow structure of the drill rod is connected to the gas channel of the connecting member; when working, the drill rod is placed vertically, and the drill bit is connected to the front end of the drill rod. By connecting the hollow structure of the drill rod with the gas channel of the connecting member, it is possible to transport high-pressure gas into the cavity of the drill bit and spray the gas out from the nozzle.

[0013] Preferably, the deformable cover comprises a plurality of movable connecting pieces which are sequentially arranged from the middle to both sides and are rotatably connected in sequence, and each of the nozzles is detachably connected to one movable connecting piece.

[0014] As a further preference, the nozzle is perpendicular to the connected movable connecting piece. This approach can ensure that when the cover surface of the deformable cover is deformed into an arc-shaped convex surface and an arc-shaped concave surface, multiple nozzles face forward and are respectively divergent and convergent, and is simple and easy to implement.

[0015] Preferably, the connecting member includes a hollow cylindrical connecting body, and a support plate rotatably connected to the front end of the connecting body; a plurality of support plates are provided on both sides of the deformation cover, and the support plates on both sides are rotatably connected to the movable connecting plates located on both sides of the deformation cover, so as to realize the connection between the connecting member and the deformation cover. Through this scheme, the connection between the connecting member and the deformation cover is realized, and a gas passage running through the front and rear ends is formed inside the connecting member.

[0016] Preferably, the drill rod includes a hollow cylindrical drill rod body and a first connecting plate vertically connected to the front end of the drill rod body; the connecting member also includes a second connecting plate vertically connected to the rear end of the connecting body; the first connecting plate and the second connecting plate are correspondingly provided with through holes; the first connecting plate and the second connecting plate are detachably connected to realize the connection between the drill rod and the connecting member, and the through holes of the first connecting plate and the second connecting plate are connected to realize the connection between the hollow structure of the drill rod and the gas channel of the connecting member.

[0017] Preferably, the driving component includes hydraulic rods arranged in one-to-one correspondence with the movable connecting pieces of the deformable cover; the connecting member also includes a third connecting plate arranged inside the hollow structure of the connecting body and connected to the inner wall of the connecting body; one end of the hydraulic rod is rotatably connected to the movable connecting piece, and the other end is rotatably connected to the third connecting plate; this scheme drives the connected movable connecting pieces to move through the extension or contraction of each hydraulic rod, thereby deforming the cover surface of the deformable cover into an arc-shaped convex surface or an arc-shaped concave surface.

[0018] Preferably, the reinforcement device also includes a gas return pipe extending from the cavity of the drill bit to the outside of the tail end of the drill rod; by providing the gas return pipe, the gas injected into the soil can be partially released through the gas return pipe. On the one hand, a suitable air pressure is maintained in the soil to prevent the formation of a high-pressure cavity in the soil due to excessive air pressure, which causes soil particles to be suspended and affects the compaction effect; on the other hand, an air flow circulation is formed to facilitate the continuous injection of air flow into the soil.

[0019] According to another aspect of the present invention, a reinforcement device for reinforcing collapsible loess foundation is proposed, which includes the drilling tool and a gas delivery unit connected to the tail of the drill rod of the drilling tool and communicated with the hollow structure of the drill rod.

[0020] Preferably, the gas delivery unit comprises a high-pressure air pump and a gas delivery pipe connecting the high-pressure air pump and the drill rod, wherein the gas delivery pipe is connected to the rear end of the drill rod and communicates with the hollow structure of the drill rod.

[0021] According to another aspect of the present invention, a method for reinforcing collapsible loess foundation is provided, the method comprising the following steps:

[0022] S1: the drill rod is positioned vertically, and the drill bit at the front end of the drill rod is located above the collapsible loess foundation to be reinforced;

[0023] S2: the drill pipe sinks, and at the same time, the drill bit sprays high-pressure airflow in a downward and divergent manner;

[0024] S3: After the drill rod sinks to a preset depth, the drill rod is lifted up, and at the same time, the drill bit sprays high-pressure airflow downward in a converging manner; until the drill rod is lifted up to a set position.

[0025] According to another aspect of the present invention, a pile driver is provided, which includes the reinforcement device, a pile driver body, a vertical bracket fixed to the pile driver body, and a drill rod support structure slidably connected to the vertical bracket; the drill rod of the reinforcement device is vertically arranged and detachably fixed to the drill rod support structure; this solution utilizes the existing pile driver for modification and is simple to implement.

[0026] In general, the above technical solution conceived by the present invention has the following technical advantages compared with the prior art:

[0027] 1. In this scheme, a driving component is used to drive the deformation of the deformation cover, so that the cover surface of the deformation cover forms an arc-shaped convex surface or an arc-shaped concave surface, and the nozzles of multiple nozzles face forward and are respectively divergent or convergent; when the reinforcement device is working, the high-pressure airflow is sprayed downward in a divergent manner to cut the collapsible loess foundation and destroy the soil structure, and the high-pressure airflow is sprayed downward in a convergent manner to form a high-pressure airflow cover to compact the soil, thereby realizing the reinforcement of the collapsible loess foundation; on the one hand, this method has a good reinforcement effect, and the soil can achieve a higher density; on the other hand, in this scheme, the drill bit only needs to sink or rise, avoiding the use of vibration to reinforce the soil and generating large noise or vibration.

[0028] 2. By setting up a gas return pipe, on the one hand, a suitable air pressure is maintained in the soil to prevent the formation of a high-pressure cavity in the soil due to excessive air pressure, which causes soil particles to suspend and affects the compaction effect; on the other hand, an air circulation is formed to facilitate the continuous injection of air into the soil.

[0029] 3. This solution utilizes the existing pile driver for transformation and is simple to implement. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 Schematic diagram of a pile driver and a reinforcement device for collapsible loess foundation according to an embodiment of the present invention;

[0031] Figure 2 is a schematic diagram of a drill rod and a drill bit when sinking according to an embodiment of the present invention;

[0032] Figure 3 yes Figure 2 Side view of

[0033] Figure 4 yes Figure 2 Bottom view of

[0034] Figure 5 is a schematic diagram of a drill rod and a drill bit when being lifted according to an embodiment of the present invention;

[0035] Figure 6 yes Figure 5 Side view of.

[0036] Throughout the drawings, the same reference numerals are used to denote the same elements or structures, wherein:

[0037] Drill rod 1, drill bit 2, gas delivery unit 3, pile driver 4, gas return pipe 5, drill rod body 11, first connecting plate 12, counterweight 13, connecting member 21, deformation cover 22, nozzle 23, driving component 24, high-pressure air pump 31, pile driver body 41, vertical bracket 42, drill rod supporting structure 43, connecting body 211, supporting plate 212, second connecting plate 213, third connecting plate 214, movable connecting piece 221, hydraulic rod 241, winch 411, vertical connecting part 431, horizontal connecting part 432. DETAILED DESCRIPTION

[0038] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention. In addition, the technical features involved in the various embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0039] like Figure 1 As shown in the figure, the reinforcement device for reinforcing collapsible loess foundation provided by the embodiment of the present invention comprises a drilling tool and a gas delivery unit 3; the drilling tool comprises a drill bit 2 and a drill rod 1 with a hollow structure inside; the gas delivery unit 3 is connected to the rear end of the drill rod 1 and communicates with the hollow structure of the drill rod 1, and the drill bit 2 is connected to the front end of the drill rod 1;

[0040] like Figure 2-Figure 6 As shown in the figure, the drill bit 2 includes a connecting member 21, a deformation cover 22, a driving component 24 and a plurality of nozzles 23; the tail end of the connecting member 21 is connected to the front end of the drill rod 1, the front end of the connecting member 21 is connected to the deformation cover 22 and the two are surrounded to form a cavity, a gas passage penetrating the front and rear ends is formed inside the connecting member 21, and the hollow structure of the drill rod 1 is connected to the gas passage of the connecting member 21; the driving component 24 is located in the cavity surrounded by the connecting member 21 and the deformation cover 22, and one end is connected to the connecting member 21, and the other end is connected to the inner side of the cover surface of the deformation cover 22, and the driving component 24 is used to drive the cover surface of the deformation cover 22 to deform; a plurality of nozzles 23 are installed on the outer side of the cover surface of the deformation cover 22;

[0041] The cover surface of the deformable cover 22 can be deformed into an arc-shaped convex surface under the drive of the driving component 24, so that multiple nozzles 23 face forward and diverge along the arc-shaped convex surface. The cover surface of the deformable cover 22 can also be deformed into an arc-shaped concave surface under the drive of the driving component 24, so that multiple nozzles 23 face forward and converge along the arc-shaped concave surface.

[0042] Through the cooperation of the above-mentioned components, when working, the drill rod 1 of the reinforcement device is arranged vertically, and the gas delivery unit 3 delivers gas to the cavity formed by the connecting member 21 and the deformation cover 22 through the hollow structure of the drill rod 1 and the gas channel of the connecting member 21, and the gas is ejected from the nozzle; in the process of the reinforcement device penetrating into the collapsible loess foundation, the drill head sinks, such as Figure 2 As shown in FIG. 1 , the driving component 24 drives the cover surface of the deformable cover 22 to deform into an arc-shaped convex surface, and multiple nozzles 23 spray high-pressure airflow downward and divergently to cut the collapsible loess foundation; in the process of the reinforcement device being pulled out of the loess foundation, the drill bit is lifted, as shown in FIG. Figure 5 As shown in the figure, the driving component 24 drives the cover surface of the deformable cover 22 to deform into an arc-shaped concave surface, and multiple nozzles 23 spray high-pressure airflow downward and in a converging shape to form a high-pressure airflow cover. The high-pressure airflow cover has a compacting effect on the soil to compact the soil, thereby achieving the reinforcement of the collapsible loess foundation.

[0043] like Figure 1 As shown in the figure, the reinforcement device for collapsible loess foundation provided by the embodiment of the present invention is installed on a pile driver 4, which also includes a pile driver body 41, a vertical bracket 42 fixed to the pile driver body 41, and a drill rod support structure 43 slidably connected to the vertical bracket 42; the drill rod 1 of the reinforcement device is vertically arranged and can be detachably fixed to the drill rod support structure 43.

[0044] Each component will be described in more detail below.

[0045] As a key component of the present invention, the deformation cover 22 includes a plurality of movable connecting pieces 221 which are arranged in sequence from the middle to both sides and are rotatably connected in sequence; in this embodiment, Figure 2-Figure 6 As shown in the figure, the deformable cover 22 includes four movable connecting pieces 221 which are arranged in sequence from the middle to both sides and are rotatably connected in sequence. In this embodiment, the movable connecting pieces 221 are all rectangular and symmetrically arranged from the middle to both sides; the rotatable connection between the movable connecting pieces 221 is hinged, specifically, the two ends of the sides of adjacent movable connecting pieces 221 that are close to each other are hinged respectively.

[0046] Each nozzle 23 is detachably connected to a movable connecting piece 221; in this embodiment, Figure 2-Figure 6As shown in the figure, the nozzles 23 are symmetrically arranged along the center lines of multiple movable connecting pieces 221, two nozzles 23 are connected to each movable connecting piece 221, and the nozzles 23 are perpendicular to the connected movable connecting piece 221; in some embodiments, the number and position of the nozzles 23, and the connection angles of the nozzles 23 and the movable connecting piece 221 can be adjusted according to actual needs to achieve the effect that when the cover surface of the deformable cover 22 is deformed into an arc-shaped convex surface, the spray direction of the nozzles 23 is forward and divergent, and when the cover surface of the deformable cover 22 is deformed into an arc-shaped concave surface, the spray direction of the nozzles 23 is forward and convergent; in this embodiment, the detachable connection between the nozzle 23 and the movable connecting piece 221 is a bolt connection.

[0047] like Figure 2 As shown in , when the drill bit 2 sinks, the cover surface of the deformable cover 22 is deformed into an arc-shaped convex surface. Specifically, the middle part of the deformable cover 22 bulges downward to form a broken line arc-shaped convex surface. The spray direction of the nozzle 23 on the deformable cover 22 is downward and divergent; Figure 5 As shown in , when the drill bit 2 is lifted, the cover surface of the deformable cover 22 is deformed into an arc-shaped concave surface. Specifically, the middle part of the deformable cover 22 is recessed upward to form a broken line arc-shaped concave surface. The spray direction of the nozzle 23 on the deformable cover 22 is downward and convergent.

[0048] The connecting member 21 includes a hollow cylindrical connecting body 211 and a supporting plate 212 rotatably connected to the front end of the connecting body 211;

[0049] A plurality of support plates 212 are provided on both sides of the deformation cover 22, and the support plates 212 on both sides are rotatably connected to the movable connecting pieces 221 on both sides of the deformation cover 22, so as to realize the connection between the connecting member 21 and the deformation cover 22. Through this solution, the connection between the connecting member 21 and the deformation cover 22 is realized, and a gas passage running through the front and rear ends is formed inside the connecting member 21; specifically, in this embodiment, Figure 2-Figure 3 , Figure 5-Figure 6As shown in the figure, the connecting body 211 is a hollow square column and its axis is parallel to the axis of the drill pipe 1. The support plate 212 is rectangular and is located below the connecting body 211. One support plate 212 is vertically arranged on both sides of the deformation cover 22. The tops of the two support plates 212 are respectively connected to the two opposite side surfaces of the connecting body 211, and the bottoms of the two support plates 212 are respectively connected to the movable connecting pieces 221 located on both sides of the deformation cover 22; more specifically, in this embodiment, the lengths of the support plates 212 and the movable connecting pieces 221 are equal, and the two ends of the bottom of the support plates 212 are respectively hinged with the two ends of the outer sides of the movable connecting pieces 221 close to them. In addition, in this embodiment, the support plate 212 is equal to the side length of the connected connecting body 211, and the two ends of the top of the support plate 212 are respectively hinged to the two ends of the side; in some embodiments, a plurality of support plates 212 are sequentially arranged along the outer sides of the movable connecting piece 221 on both sides of the deformation cover 22, and the bottom of each support plate 212 is hinged to the adjacent movable connecting piece 221, and the top is hinged to the side of the adjacent connecting body 211; it can be understood that the length of the support plate 212 can be different from the length of the movable connecting piece 221, and the length of the side of the connected connecting body 211 can also be different;

[0050] In other embodiments, the connecting body 211 is a hollow cylinder and the support plate 212 is arc-shaped. In these embodiments, a support plate 212 can be provided on each side of the deformation cover 22, and each support plate 212 is hinged to the side wall of the connecting body 211 and the movable connecting piece 221 adjacent to it at only one place. Alternatively, two support plates 212 can be provided on each side of the deformation cover 22, and the two support plates 212 are arranged along the outer side edges of the movable connecting piece 221 adjacent to it, and are symmetrical along the center line of the outer side edges, and are hinged to the side wall of the connecting body 211 and the movable connecting piece 221 adjacent to it at only one place.

[0051] like Figure 2-Figure 3 , Figure 5-Figure 6As shown in the figure, the drill rod 1 includes a hollow cylindrical drill rod body 11 and a first connecting plate 12 vertically connected to the front end of the drill rod body 11; in this embodiment, the drill rod body 11 is a hollow square column, and in some embodiments, the drill rod body 11 is a hollow cylinder; the connecting member 21 also includes a second connecting plate 213 vertically connected to the rear end of the connecting body 211; the first connecting plate 12 and the second connecting plate 213 are correspondingly provided with through holes; the first connecting plate 12 and the second connecting plate 213 are detachably connected to realize the connection between the drill rod 1 and the connecting member 21 , and the through holes of the first connecting plate 12 and the second connecting plate 213 are connected, so that the hollow structure of the drill pipe 1 is connected with the gas channel of the connecting member 21, and the high-pressure airflow can flow into the cavity formed by the connecting structure 21 and the deformation cover 22 through the hollow structure of the drill pipe 1 and the gas channel of the connecting member 21; in some embodiments, further, the first connecting plate 12 and the second connecting plate 213 are grid plates to achieve the function of allowing the high-pressure airflow to pass; in this embodiment, the detachable connection of the first connecting plate 12 and the second connecting plate 213 is a bolt connection.

[0052] like Figure 1 As shown in FIG, the top of the drill pipe 1 of this embodiment is also provided with a counterweight 13 to provide downward pressure.

[0053] like Figure 2-Figure 3 , Figure 5-Figure 6As shown in, the driving component 24 includes a hydraulic rod 241 arranged in a one-to-one correspondence with the movable connecting piece 221 of the deformation cover 22; the connecting member 21 also includes a third connecting plate 214 arranged inside the hollow structure of the connecting body 211 and connected to the inner wall of the connecting body 211; one end of the hydraulic rod 241 is rotatably connected to the movable connecting piece 221, and the other end is rotatably connected to the third connecting plate 214; in some embodiments, the third connecting plate 214 can also be omitted, so that the end of the hydraulic rod 241 away from the movable connecting piece 221 is rotatably connected to the second connecting plate 213; in this embodiment, four hydraulic rods 241 are provided, one end of the hydraulic rod 241 is respectively connected to the center of the four movable connecting pieces 221, and the other end is close to each other and connected to the third connecting plate 214; the rotatable connection of the hydraulic rod 241 with the movable connecting piece 221 and the third connecting plate 214 is hinged; in this embodiment, four hydraulic oil pipes are also provided, one end of the four hydraulic oil pipes is respectively connected to four hydraulic The hydraulic oil inlet of the pressure rod 241 is connected, and the other end of the hydraulic oil pipe is connected to the hydraulic system of the pile driver body 41; specifically, the hydraulic oil pipe passes through the third connecting plate 214, the second connecting plate 213 and the first connecting plate 12, extends along the inside of the drill rod body 11 and extends out of the drill rod 1 to connect with the hydraulic system of the pile driver body 41; the hydraulic oil pipe is used to transmit hydraulic pressure from the hydraulic system of the pile driver body 41 to the hydraulic rod 241 to drive the hydraulic rod 241. This solution makes full use of the system of the pile driver body 41 itself and has the advantage of simple implementation; when the reinforcement device is working, the hydraulic rod 241 extends or contracts accordingly, and drives the connected movable connecting piece 221 to move, thereby driving the shape of the deformation cover 22 to change, so that the cover surface of the deformation cover 22 switches between the arc convex surface and the arc concave surface; according to the structural characteristics of the collapsible loess foundation in different sites and different depths, the extension and contraction of the hydraulic rod 241 can be adjusted to adjust the shape of the cover surface of the deformation cover 22 and the angle of the nozzle 23.

[0054] like Figure 1 As shown in the figure, the reinforcement device of this embodiment also includes a gas return pipe 5 extending from the drill bit 2 to the outside of the tail end of the drill rod 1, and the end of the gas return pipe 5 close to the drill bit 2 is located in the cavity formed by the deformable cover 22 and the connecting member 21; in this embodiment, the gas return pipe 5 passes through the third connecting plate 214, the second connecting plate 213 and the first connecting plate 12, and extends along the hollow structure of the drill rod 1 to the top of the drill rod 1, and then passes through the top of the drill rod 1; by providing the gas return pipe 5, the gas injected into the soil can be partially released into the ground atmosphere through the gas return pipe 5, so as to maintain a suitable air pressure in the soil and form an airflow circulation.

[0055] The gas delivery unit 3 includes a high-pressure air pump 31 and an air pipe connecting the high-pressure air pump 31 and the drill rod 1. The air pipe is connected to the rear end of the drill rod 1 and communicates with the hollow structure of the drill rod 1. In this embodiment, the air pipe is a high-pressure hose, which is inserted into the drill rod body 11 from the top and fixed by a nut. The high-pressure air pump 31 is used to provide a high-pressure airflow. The air pipe introduces the high-pressure airflow into the drill rod 1, and guides the high-pressure airflow into the cavity surrounded by the connecting structure 21 and the deformation cover 22 through the hollow structure of the drill rod 1 and the gas channel of the connecting member 21, and then sprays it out from the nozzle 23. In this embodiment, the high-pressure air pump 31 is installed on the drill rod support structure 43; Figure 1 As shown in the figure, the drill rod support structure 43 includes a vertical connection part 431 and a horizontal connection part 432. The vertical connection part 431 is slidably connected to the vertical support 42 to drive the drill rod 1 to move vertically. The horizontal connection part 432 is used to connect the drill rod 1 and is also used to install the high-pressure air pump 31. The drill rod 1 is vertically arranged, and the top end of the drill rod 1 passes through the horizontal connection part 432 and is bolted to the horizontal connection part 432.

[0056] The pile driver body 41 of this embodiment includes a control system, a hydraulic system and a power system; the control system is connected to the hydraulic system and the power system by electrical signals to control the actions of the hydraulic system and the power system; the hydraulic system transmits hydraulic oil to the hydraulic rod 241 through a hydraulic oil pipe to make the hydraulic rod 241 extend and retract and thereby drive the deformation cover 22 to deform; the power system includes a power device and a winch 411, and the power device can be an electric motor or a fuel engine to provide power for the winch 411; the transmission end of the winch 411 is connected to the drill rod support structure 43 to drive the drill rod support structure 43 to slide up and down along the vertical support 42, further driving the drill rod 1 to sink or rise; the control system is also connected to the high-pressure air pump 31 of the gas delivery unit 3 to control the opening and closing of the high-pressure airflow, as well as the pressure of the high-pressure airflow.

[0057] The method for reinforcing a collapsible loess foundation using the reinforcement device of this embodiment comprises the following steps:

[0058] S1: The drill rod 1 is vertically positioned, and the drill bit 2 at the front end of the drill rod 1 is located above the collapsible loess foundation to be reinforced; specifically, in this embodiment, the pile driver 4 is first positioned, and then the line is laid to position the drill rod 1;

[0059] S2: The drill pipe 1 sinks, and the drill bit 2 simultaneously ejects high-pressure airflow in a downward and divergent manner;

[0060] Specifically, in this embodiment, the power device is started to provide power for the winch 411, and the winch 411 drives the drill rod support structure 43 to move downward along the vertical bracket 42, thereby driving the drill rod 1 to sink; the hydraulic system is started, the hydraulic rod 241 is stretched, so that the middle of the deformation cover 22 bulges, and the cover surface of the deformation cover 22 forms a broken arc convex surface, and the spray direction of the nozzle 23 is downward and divergent; the high-pressure air pump 31 is started, and the nozzle 23 sprays high-pressure airflow; the high-pressure airflow destroys the collapsible loess structure, breaks up the soil particles and rearranges them, and the high-pressure airflow helps the drill rod 1 to sink; at the same time, the gas return pipe 5 is connected to form an airflow circulation, so as to facilitate the continuous injection of the airflow into the soil;

[0061] S3: After the drill rod 1 sinks to a preset depth, the drill rod 1 is lifted up, and at the same time, the drill bit 2 sprays high-pressure airflow downward in a converging manner; until the drill rod 1 is lifted up to a set position;

[0062] Specifically, the winch 411 drives the drill rod support structure 43 to move upward along the vertical bracket 42, thereby driving the drill rod 1 to lift; the hydraulic system drives the hydraulic rod 241 to contract, causing the middle of the deformation cover 22 to concave upward, and the cover surface of the deformation cover 22 forms a broken arc concave surface, and the nozzle 23 sprays high-pressure airflow, and the spray direction is downward and convergent; a high-pressure airflow cover is formed under the deformation cover 22, and the high-pressure airflow cover has a compacting effect on the soil below, making the soil below dense; at the same time, the gas return pipe 5 is turned on, so that the gas injected into the soil can be partially released into the ground atmosphere through the gas return pipe 5.

[0063] After completing the above steps, the pile driver 4 moves to the next pile position and repeats the above steps.

[0064] The above examples are used to illustrate the reinforcement device and method for reinforcing collapsible loess foundation of the present invention, and do not constitute a limitation on the protection scope of the present invention.

[0065] In summary, according to the reinforcement device and method of the present invention, a high-pressure airflow hood is formed by spraying high-pressure airflow downward and in a converging shape. The high-pressure airflow hood has a compacting effect on the soil to compact the soil, thereby achieving the reinforcement of the collapsible loess foundation. This method has a good reinforcement effect and can achieve a higher density. In addition, in this solution, the drill rod does not need to vibrate, does not generate loud noise or vibration, and avoids noise pollution. Therefore, it is particularly suitable for applications such as reinforcing collapsible loess foundations.

[0066] It will be easily understood by those skilled in the art that 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 in the protection scope of the present invention.

Claims

1. A drill bit, characterized in that: It comprises a connecting member (21), a deformation cover (22), a driving component (24) and a plurality of nozzles (23); The rear end of the connecting member (21) is used to be connected to the drill rod (1), and the front end is connected to the deformable cover (22), and the two are surrounded by a cavity. A gas passage that passes through the front and rear ends is formed inside the connecting member (21); the driving component (24) is located in the cavity, and one end is connected to the connecting member (21), and the other end is connected to the inner side of the cover surface of the deformable cover (22); the driving component (24) is used to drive the cover surface of the deformable cover (22) to deform; the multiple nozzles (23) are installed on the outer side of the cover surface of the deformable cover (22); The cover surface of the deformable cover (22) can be deformed into an arcuate convex surface under the drive of the driving component (24), so that the multiple nozzles (23) face forward and diverge along the arcuate convex surface; the cover surface of the deformable cover (22) can also be deformed into an arcuate concave surface under the drive of the driving component, so that the multiple nozzles (23) face forward and converge along the arcuate concave surface.

2. A drilling tool provided with a drill bit according to claim 1, characterized in that: It also comprises a drill rod (1) with a hollow structure inside, the front end of the drill rod (1) is connected to the rear end of the connecting member (21), and the hollow structure of the drill rod (1) is in communication with the gas passage of the connecting member (21).

3. The drilling tool according to claim 2, characterized in that The deformable cover (22) comprises a plurality of movable connecting pieces (221) which are arranged in sequence from the middle to both sides and are rotatably connected in sequence, and each of the nozzles (23) is detachably connected to a movable connecting piece (221).

4. The drilling tool according to claim 3, characterized in that The connecting member (21) comprises a hollow columnar connecting body (211), and a supporting plate (212) rotatably connected to the front end of the connecting body (211); a plurality of supporting plates (212) are provided on both sides of the deformation cover (22), and the supporting plates (212) on both sides are rotatably connected to the movable connecting plates (221) located on both sides of the deformation cover (22), so as to realize the connection between the connecting member (21) and the deformation cover (22).

5. The drilling tool according to claim 4, characterized in that The drill rod (1) comprises a hollow columnar drill rod body (11) and a first connecting plate (12) vertically connected to the front end of the drill rod body (11); the connecting member (21) further comprises a second connecting plate (213) vertically connected to the rear end of the connecting body (211); the first connecting plate (12) and the second connecting plate (213) are correspondingly provided with through holes; the first connecting plate (12) and the second connecting plate (213) are detachably connected to realize the connection between the drill rod (1) and the connecting member (21), and the through holes of the first connecting plate (12) and the second connecting plate (213) are connected to connect the hollow structure of the drill rod (1) with the gas passage of the connecting member (21).

6. The drilling tool according to claim 5, characterized in that The driving component (24) includes a hydraulic rod (241) which is arranged in a one-to-one correspondence with the movable connecting piece (221) of the deformation cover (22); the connecting member (21) also includes a third connecting plate (214) which is arranged inside the hollow structure of the connecting body (211) and connected to the inner wall of the connecting body (211); one end of the hydraulic rod (241) is rotatably connected to the movable connecting piece (221), and the other end is rotatably connected to the third connecting plate (214).

7. The drilling tool according to claim 2, characterized in that: It also comprises a gas return pipe (5) extending from the cavity of the drill bit (2) to the outside of the rear end of the drill rod (1).

8. A reinforcement device provided with a drilling tool as claimed in any one of claims 2 to 7, characterized in that: It also comprises a gas delivery unit (3) connected to the rear end of the drill rod (1) and in communication with the hollow structure of the drill rod (1).

9. A method for reinforcing collapsible loess foundation using the reinforcement device according to claim 8, characterized in that: The following steps are involved: S1: the drill rod (1) is positioned vertically, and the drill bit (2) at the front end of the drill rod (1) is located above the collapsible loess foundation to be reinforced; S2: the drill rod (1) sinks, and at the same time the drill bit (2) sprays high-pressure airflow in a downward and divergent manner; S3: After the drill rod (1) sinks to a preset depth, the drill rod (1) is lifted up, and at the same time, the drill bit (2) sprays high-pressure airflow downward in a converging manner; until the drill rod (1) is lifted up to a set position.

10. A pile driver (4) provided with the reinforcement device according to claim 8, characterized in that: The pile driver (4) further comprises a pile driver body (41), a vertical bracket (42) fixed to the pile driver body (41), and a drill rod support structure (43) slidably connected to the vertical bracket (42); the drill rod (1) of the reinforcement device is arranged vertically and can be detachably fixed to the drill rod support structure (43).

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