A double-layer reverse spiral pile side soil ring cutting device

Abstract

The invention relates to the field of civil engineering technology, and in particular to a double-layer reverse spiral pile side soil ring cutting device; the device comprises a ring cutting mechanism arranged on the side of the pile foundation and a first driving mechanism for driving the ring cutting mechanism to ring cut; the ring cutting mechanism comprises a ring cutting pipe, the ring cutting pipe embraces the pile foundation, a ring cutting head is arranged below the ring cutting pipe, and a spiral drill cutter is arranged on the outer peripheral side of the ring cutting pipe; the ring cutting mechanism is driven by the first driving mechanism to ring cut the soil on the side of the pile, so that an annular cavity is formed on the side of the pile, and then sand and gravel are poured into the cavity to overcome the influence of collapsible loess on the pile foundation, improve the bearing capacity of the pile foundation, greatly reduce the depth of the pile foundation, and reduce labor. The pile side soil ring cutting device has a simple structure, is easy to operate, has a low cost, occupies a small area on the construction site, and is suitable for various construction occasions.

Description

Technical Field

[0001] The invention relates to the technical field of civil engineering, and in particular to a double-layer reverse spiral pile side soil ring cutting device. Background Art

[0002] Collapsible loess is widely distributed in my country. It has low humidity and high porosity. When not soaked in water, it is generally strong and has low compressibility. However, when soaked in water, the soil structure will be quickly destroyed, resulting in large additional subsidence and rapid decrease in strength. The downward drag force generated by the negative friction on the pile side in pile foundation engineering may cause pile damage and uneven subsidence of the pile foundation, seriously affecting the safety of the building.

[0003] The treatment of collapsible loess foundation can be to improve the properties and structure of the soil and reduce the water permeability of the soil; or use cushioning or strong tamping to improve the bearing capacity of the foundation and strengthen the foundation. Different treatment methods are suitable for different foundation sites. Most treatment methods to improve the bearing capacity of pile foundations have problems such as large construction site area, deep pile foundations, high labor costs and high construction costs.

[0004] The way to improve the properties and structure of the soil requires the treatment of the large area of ​​collapsible loess around the piles, and the underlying soil still has the problem of negative friction on the pile foundation after being soaked by rainwater. Summary of the invention

[0005] The purpose of the present invention is to provide a double-layer reverse spiral pile side soil ring cutting device to solve the problems mentioned in the prior art that most of the treatment methods for improving the bearing capacity of pile foundations in loess areas with severe collapsibility have the problems of large construction site area, deep pile foundation, high labor cost and high construction cost.

[0006] In order to solve the above problems, the technical solution provided by the present invention is a double-layer reverse spiral pile side soil ring cutting device, comprising a ring cutting mechanism arranged on the side of the pile foundation and a first driving mechanism for driving the ring cutting mechanism to ring cut;

[0007] The ring cutting mechanism comprises a ring cutting pipe, which surrounds the pile foundation, a ring cutting head is arranged below the ring cutting pipe, and a spiral drill cutter is arranged on the outer peripheral side of the ring cutting pipe.

[0008] After the pile foundation has been constructed and solidified, the soil ring cutting device on the pile side is hoisted and placed on the upper part of the pile foundation under the drive of the first driving mechanism, and is kept concentric with the pile foundation as much as possible. Under the drive of the first driving mechanism, the ring cutting head first cuts into the soil. As the ring cutting head goes deeper, the spiral drill cuts into the soil.

[0009] Under the rotating circular cutting action of the spiral drill, the soil in the upper part of the pile foundation is circularly cut to form an annular cavity, and sand and gravel are injected into the annular cavity, that is, the collapsible loess around the pile foundation is replaced with sand and gravel. Sand and gravel have high strength and low compressibility and are not affected by the adverse effects of water immersion.

[0010] The pile foundation is cut in rings using a pile-side soil cutting device to overcome the impact of collapsible loess on the pile foundation and improve the bearing capacity of the pile foundation. This can greatly reduce the depth of the pile foundation, reduce labor, occupy a small area on the construction site, and reduce the cost.

[0011] Preferably, a pile protection mechanism is provided on the inner side of the ring-cutting pipe, and the pile protection mechanism is movably connected to the ring-cutting pipe in an annular manner.

[0012] Since the pile protection mechanism is movably connected to the ring-cutting pipe in an annular manner, the pile protection mechanism is not driven by the first driving mechanism, that is, when the ring-cutting mechanism rotates to ring-cut the soil on the pile side, the pile protection mechanism protects the pile foundation from the influence of the ring-cutting torsional force.

[0013] Preferably, an outer pipe sleeve is also provided on the outer side of the spiral drill cutter.

[0014] The outer tube sleeve can be rotated with the spiral drill cutter or can be non-rotating. The outer tube sleeve is arranged to prevent the annular cavity from collapsing on the one hand and facilitate the extraction of the ring cutting device on the other hand.

[0015] Preferably, the outer sleeve rotates in the opposite direction to the circumcision mechanism;

[0016] The outer sleeve is driven by a second driving mechanism.

[0017] The outer sleeve and the ring cutting pipe rotate in opposite directions, forming a double-layer reverse spiral pile side soil ring cutting process, which is conducive to extracting the ring cut soil. The first driving mechanism and the second driving mechanism can be a driving mechanism with forward and reverse driving directions.

[0018] Preferably, the annular cutting head is concave toward the inner side of the annular cutting pipe, and its inner diameter is smaller than the inner diameter of the pile protection mechanism and larger than the pile foundation diameter.

[0019] During the ring cutting process, in order to enable the pile protection mechanism to descend smoothly, the ring cutting head is concave toward the inside of the ring cutting pipe, and the inner diameter of the ring cutting head is smaller than the inner diameter of the pile protection mechanism and larger than the pile foundation diameter.

[0020] Preferably, the ring cutting head includes a cutter arranged at the bottom, the outer cutting surface of the cutter is inclined toward the ring cutting tube to form a first inclined surface, and the inner cutting surface of the cutter is inclined toward the ring cutting tube to form a second inclined surface, the first inclined surface is at an acute angle to the vertical line, and the angle between the second inclined surface and the vertical line is smaller than the first inclined surface and is greater than or equal to 0°.

[0021] In order to enable the entire circular cutting device to descend smoothly, the diameter of the circular cutter is minimized, and the arrangement of the first inclined surface and the second inclined surface also enables the entire device to descend smoothly.

[0022] Preferably, the annular cutting head is sawtooth-shaped.

[0023] The circular cutting head is set to be sawtooth-shaped, which improves the sharpness of the cutter and improves the circular cutting efficiency of the circular cutting head.

[0024] Preferably, the outer sleeve has a depth less than the depth of the auger cutter;

[0025] The inner diameter of the outer sleeve is inclined toward the outer diameter, and the depth of the inner diameter is greater than the depth of the outer diameter.

[0026] During the spiral cutting process of the spiral drill, the outer pipe sleeve follows closely and penetrates into the cutting space, and the lower end of the outer pipe sleeve is arranged as an inclined surface, which is conducive to the downward movement of the outer pipe sleeve.

[0027] Preferably, the pile protection mechanism is an annular protection tube or a plurality of annular protection rings evenly distributed from top to bottom, and the annular protection tube or the annular protection ring is movably connected to the annular cutting tube in an annular manner.

[0028] The annular protective tube or annular protective ring is a steel pipe ring or a rubber foam ring.

[0029] The corresponding shape and material are selected for the pile protection mechanism 3 according to the comprehensive factors of the required torsional force and the degree of collapsibility of the soil at the pile side.

[0030] Beneficial effects of the present invention:

[0031] The first driving mechanism drives the circumcision mechanism to circumscribe the soil around the pile to form an annular cavity around the pile, and then pour sand and gravel into the cavity to overcome the influence of collapsible loess on the pile foundation, improve the bearing capacity of the pile foundation, greatly reduce the depth of the pile foundation, and reduce labor. The pile side soil circumcision device has a simple structure, is easy to operate, has a low cost, occupies a small area on the construction site, and is suitable for various construction occasions.

[0032] The present invention is described in detail below with reference to the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 It is a schematic diagram of the structure of the pile side soil ring cutting device;

[0034] Figure 2 It is a schematic diagram of the cross-sectional structure of the pile side soil ring cutting device;

[0035] Figure 3 This is a partial enlarged view of the pile side soil ring cutting device in the A direction;

[0036] Figure 4 It is the first annular clamping method of the pile protection mechanism and the ring cutting pipe;

[0037] Figure 5 It is the second annular clamping method of the pile protection mechanism and the annular cutting pipe.

[0038] Explanation of the accompanying drawings: 1-circumferential cutting mechanism; 11-circumferential cutting pipe; 12-circumferential cutting head; 121-cutter; 122-first inclined plane; 123-second inclined plane; 13-spiral drill; 2-first driving mechanism; 3-pile protection mechanism; 4-outer pipe sleeve; 5-second driving mechanism; 6-buckle; 7-slot; 8-intermediate buckle. DETAILED DESCRIPTION

[0039] The present invention is further described below in conjunction with the embodiments, but those skilled in the art will understand that the following examples are only used to illustrate the present invention and should not be considered to limit the scope of the present invention. If no specific conditions are specified in the examples, they are carried out under conventional conditions or conditions recommended by the manufacturer. The reagents or instruments used without indicating the manufacturer are all conventional products that can be purchased commercially; the specific embodiments described are only used to explain the principles of the present invention and are not used to limit the present invention.

[0040] In view of the existing technology, in the loess area with severe collapsibility, most of the treatment methods for improving the bearing capacity of pile foundations have the problems of large construction site area, deep pile foundation, high labor cost and high cost. The technical solution of the present invention is as follows: Figure 1 , Figure 2 and Figure 3 A double-layer reverse spiral pile side soil ring cutting device is shown, comprising a ring cutting mechanism 1 arranged around the pile foundation and a first driving mechanism 2 for driving the ring cutting mechanism 1 to perform ring cutting;

[0041] The ring cutting mechanism 1 comprises a ring cutting pipe 11 , which surrounds the pile foundation, a ring cutting head 12 is arranged below the ring cutting pipe 11 , and a spiral drill cutter 13 is arranged on the outer peripheral side of the ring cutting pipe 11 .

[0042] After the pile foundation is solidified, the soil ring cutting device on the pile side is hoisted and placed on the upper part of the pile foundation under the drive of the first driving mechanism 2, and is kept concentric with the pile foundation as much as possible. The first driving mechanism 2 can select an ordinary unidirectional driving motor, which can be an ordinary drilling driving motor. The support frame of the first driving mechanism 2 is placed on a movable vehicle. Under the drive of the first driving mechanism 2, the ring cutting head 12 first cuts into the soil. As the ring cutting head 12 goes deeper, the spiral drill cutter 13 cuts into the soil.

[0043] The spiral drill cutter 13 is spirally shaped around the ring cutting pipe 11. Under the rotating ring cutting action of the spiral drill cutter 13, the soil in the upper part of the pile foundation is ring cut to form an annular cavity. The ring width is at least 10 centimeters, which is determined according to the depth and the required strength. Sand and gravel are poured into the annular cavity. Sand and gravel can be poured while pulling up the ring cutting device, that is, the collapsible loess around the pile foundation is replaced with sand and gravel. The strength of sand and gravel is high and the compressibility is small. It is not affected by the adverse effects of the collapsible loess on the pile foundation after being soaked in water. The required depth of the pile foundation annular cavity is determined according to the thickness of the local collapsible loess and the pile depth of the pile foundation. The depth generally ranges from more than ten meters to several tens of meters. Generally, the depth of the annular cavity is to the critical point of the two soil layers, that is, the neutral point. This process can effectively reduce the depth of the pile foundation under the condition of the same bearing capacity.

[0044] The first driving mechanism 2 drives the circumferential cutting mechanism 1 to circumscribe the soil on the pile side to form an annular cavity on the pile side, and then pour sand and gravel into the cavity to overcome the influence of collapsible loess on the pile foundation, improve the bearing capacity of the pile foundation, and greatly reduce the depth of the pile foundation. The pile side soil circumferential cutting device has a simple structure, is easy to operate, has a low cost, occupies a small area on the construction site, and is suitable for various construction occasions.

[0045] Embodiment 1

[0046] In order to prevent the influence of the torsion force of the ring cutting on the pile foundation when the ring cutting mechanism 1 is ring cutting, a pile protection mechanism 3 is provided inside the ring cutting pipe 11, and the pile protection mechanism 3 is connected to the ring cutting pipe 11 in an annular manner. Since the pile protection mechanism 3 is connected to the ring cutting pipe 11 in an annular manner, the pile protection mechanism 1 is not driven by the first driving mechanism 2, that is, when the ring cutting mechanism 1 rotates to ring cut the soil on the side of the pile, the pile protection mechanism 3 protects the pile foundation from the influence of the torsion force of the ring cutting.

[0047] The pile protection mechanism 3 is an annular protection tube or a plurality of annular protection rings evenly distributed from top to bottom. The annular protection tube or the annular protection ring is movably connected to the annular cutting tube 11 in an annular manner by ball connection or clamping.

[0048] The annular protective tube or annular protective ring is a steel pipe ring or a rubber foam ring.

[0049] When the pile protection mechanism 3 is an annular protective tube, the annular torsional force from the annular cutting mechanism 1 is avoided, and the contact force can be effectively dispersed, thereby protecting the pile foundation. When the pile protection mechanism 3 is an annular protective ring evenly distributed from top to bottom, the annular torsional force from the annular cutting mechanism 1 can be avoided while reducing the contact area with the pile foundation. According to the comprehensive factors of the required torsional force and the degree of collapsibility of the soil on the pile side, the corresponding shape and material are selected for the pile protection mechanism 3.

[0050] The annular ball connection is a known ball connection method. The annular clamping connection can be as follows Figure 4 As shown, it is connected by a buckle 6 and a slot 7, or it can be as follows Figure 5As shown, the intermediate buckle 8 is connected with the clamping groove 7 of the pile protection mechanism 3 and the clamping groove 7 of the ring cutting pipe 11. The annular movable connection between the ring cutting pipe 11 and the pile protection mechanism 3 can also be other connection modes, not limited to the annular ball connection and the annular buckle connection.

[0051] Embodiment 2

[0052] An outer tube sleeve 4 is also provided outside the spiral drill cutter 13. The outer tube sleeve 4 may rotate with the spiral drill cutter 13 or may not rotate. The provision of the outer tube sleeve 4 prevents the annular cavity from collapsing on the one hand, and facilitates the extraction of the ring cutting device on the other hand.

[0053] The outer tube sleeve 4 can be provided by adding a fixing frame outside the first driving mechanism 2, and the fixing frame is connected with the outer tube sleeve 4 to achieve fixation. The first driving mechanism 2 of the second embodiment can select a common motor.

[0054] The depth of the outer tube sleeve 4 is less than the depth of the spiral drill cutter 13;

[0055] The inner diameter of the outer sleeve 4 is inclined toward the outer diameter, and the depth of the inner diameter is greater than the depth of the outer diameter.

[0056] During the spiral cutting of the spiral drill 13, in order to prevent the outer pipe sleeve 4 from being subjected to upward resistance of the soil, the setting depth of the outer pipe sleeve 4 is less than the depth of the spiral drill 13. The outer pipe sleeve 4 follows closely and goes deep into the cutting space. The lower end of the outer pipe sleeve 4 is set as an inclined surface, which is conducive to the smooth descent of the outer pipe sleeve 4.

[0057] Embodiment 3

[0058] On the basis of the second embodiment, the rotation direction of the outer sleeve 4 is opposite to the rotation direction of the circumcision mechanism 1 , and the outer sleeve 4 is driven by the second driving mechanism 5 .

[0059] The outer sleeve 4 rotates in the opposite direction to the ring cutting pipe 11, forming a double-layer reverse spiral pile side soil ring cutting process, which is conducive to extracting the ring cut soil and pulling out the ring cutting device. The second drive mechanism 5 can be a separate drive motor, or the first drive mechanism 2 and the second drive mechanism 5 can be a drive mechanism with forward and reverse direction drive. The drive technology with forward and reverse direction rotation function on the market is already very mature, and only needs the size and power to meet the requirements of the ring cutting mechanism 1, such as the forward and reverse motor series of Zhongda Motor.

[0060] During the circumcision process, in order to allow the pile protection mechanism 1 to move downward smoothly and to leave a certain downward space for the pile protection mechanism 1, the circumcision head 12 is recessed toward the inner side of the circumcision tube 11, and its inner diameter is smaller than the inner diameter of the pile protection mechanism 3 and larger than the pile foundation diameter, which can be 6 to 14 cm larger than the pile foundation diameter.

[0061] The ring cutting head 12 includes a cutter 121 arranged at the bottom, the outer cutting surface of the cutter 121 is inclined toward the ring cutting tube 11 to form a first inclined surface 122, and the inner cutting surface of the cutter 121 is inclined toward the ring cutting tube 11 to form a second inclined surface 123. The first inclined surface 122 is at an acute angle to the vertical line, and the angle between the second inclined surface 123 and the vertical line is smaller than the first inclined surface and is greater than or equal to 0°.

[0062] In order to enable the pile side soil ring cutting device to descend smoothly as a whole, the diameter of the ring cutter 121 is minimized, and the arrangement of the first inclined surface 122 and the second inclined surface 123 also enables the device to descend smoothly as a whole.

[0063] In order to improve the cutting efficiency of the cutting head 12 and the sharpness of the cutter 121, the cutting head 12 is configured to be serrated, and / or the lower portion of the outer sleeve 4 is also serrated to facilitate the downward movement of the outer sleeve 4.

[0064] Working process: First, according to the thickness of the collapsible loess where the pile foundation is located, the depth of the pile foundation and the height of the corresponding soil ring cutting are calculated. Secondly, after the pile foundation construction solidifies, under the drive of the first driving mechanism 2, the pile side soil ring cutting device is hoisted and placed on the upper part of the pile foundation, and is kept concentric with the pile foundation as much as possible. Under the drive of the first driving mechanism 2, the ring cutting head 12 first cuts into the soil. As the ring cutting head 12 goes deeper, the spiral drill 13 cuts into the soil, and then the outer pipe sleeve 4 enters the annular cavity. Under the drive of the second driving mechanism 5, the outer pipe sleeve 4 rotates in the opposite direction to the ring cutting pipe 11, forming a double-layer reverse spiral pile side soil ring cutting process. During the ring cutting process, the ring cut soil is pulled out. Secondly, after reaching the required soil ring cutting depth, fill the ring cutting space with sand and gravel, and rotate vertically upward in the opposite direction while filling the sand and gravel, and pull out the pile side soil ring cutting device; finally, compact the filled sand and gravel to improve the bearing capacity of the pile foundation.

[0065] In summary, in order to solve the problems in the prior art that most of the treatment methods for improving the bearing capacity of pile foundations in severely collapsible loess areas have the following problems: large construction site area, deep pile foundation, high labor cost, high construction cost, etc., the present invention provides a double-layer reverse spiral pile side soil ring cutting device, which drives the ring cutting mechanism 1 through the first driving mechanism 2 to ring cut the soil around the pile to form an annular cavity around the pile, and then pour sand and gravel into the cavity to overcome the influence of collapsible loess on the pile foundation, improve the bearing capacity of the pile foundation, greatly reduce the depth of the pile foundation, and reduce labor. The pile side soil ring cutting device has a simple structure, is easy to operate, has a low cost, occupies a small construction site area, and is suitable for various construction occasions.

[0066] In the description of this specification, the description with reference to the terms "one embodiment", "example", "specific example", etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0067] The preferred embodiments of the present invention disclosed above are only used to help explain the present invention. The preferred embodiments do not describe all the details in detail, nor do they limit the invention to only specific implementation methods. Obviously, many modifications and changes can be made according to the content of this specification. This specification selects and specifically describes these embodiments in order to better explain the principles and practical applications of the present invention, so that those skilled in the art can understand and use the present invention well. The present invention is limited only by the claims and their full scope and equivalents.

Claims

1. A double-layer reverse spiral pile side soil ring cutting device, characterized in that: It comprises a ring cutting mechanism (1) arranged on the circumference of a pile foundation and a first driving mechanism (2) for driving the ring cutting mechanism (1) to perform ring cutting; The ring cutting mechanism (1) comprises a ring cutting pipe (11), the ring cutting pipe (11) surrounds the pile foundation, a ring cutting head (12) is provided below the ring cutting pipe (11), and a spiral drill cutter (13) is provided on the outer peripheral side of the ring cutting pipe (11); A pile protection mechanism (3) is provided inside the annular cutting pipe (11), and the pile protection mechanism (3) is movably connected to the annular cutting pipe (11) in an annular manner; An outer tube sleeve (4) is also provided on the outer side of the spiral drill cutter (13); The outer sleeve (4) rotates in a direction opposite to that of the annular cutting mechanism (1); The outer sleeve (4) is driven by a second driving mechanism (5); The ring cutting head (12) is concave toward the inner side of the ring cutting pipe (11), and its inner diameter is smaller than the inner diameter of the pile protection mechanism (3) and larger than the pile foundation diameter; The ring cutting head (12) comprises a cutter (121) arranged at the bottom, the outer cutting surface of the cutter (121) is inclined toward the ring cutting tube (11) to form a first inclined surface (122), and the inner cutting surface of the cutter (121) is inclined toward the ring cutting tube (11) to form a second inclined surface (123), the first inclined surface (122) and the vertical line form an acute angle, and the angle between the second inclined surface (123) and the vertical line is smaller than the first inclined surface and is greater than or equal to 0°.

2. The double-layer reverse spiral pile side soil ring cutting device according to claim 1 is characterized by: The circular cutting head (12) is sawtooth-shaped.

3. The double-layer reverse spiral pile side soil ring cutting device according to claim 1 is characterized by: The depth of the outer tube sleeve (4) is less than the depth of the spiral drill cutter (13); The inner diameter of the outer pipe sleeve (4) is inclined toward the outer diameter, and the depth of the inner diameter is greater than the depth of the outer diameter.

4. The double-layer reverse spiral pile side soil ring cutting device according to claim 1 is characterized by: The pile protection mechanism (3) is an annular protection tube or a plurality of annular protection rings evenly distributed from top to bottom, and the annular protection tube or the annular protection ring is movably connected to the annular cutting tube (11) in an annular manner.

5. The double-layer reverse spiral pile side soil ring cutting device according to claim 4 is characterized in that: The annular protective tube or annular protective ring is a steel pipe ring or a rubber foam ring.

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