CN210105746U

CN210105746U - Thread fit type composite drilling tool and profile pile

Info

Publication number: CN210105746U
Application number: CN201920987115.2U
Authority: CN
Inventors: 李广信
Original assignee: Individual
Current assignee: Individual
Priority date: 2019-06-27
Filing date: 2019-06-27
Publication date: 2020-02-21
Anticipated expiration: 2029-06-27

Abstract

The utility model belongs to the technical field of civil engineering technique and specifically relates to a screw-thread fit formula composite drilling tool and shaped pile are related to. The drilling tool comprises a first power drilling tool and a second power drilling tool; the spiral blade on the outer side of the core tube of the first power drilling tool is in an external thread structure; the second power drilling tool is composed of a drilling tool main body with a combined function of extruding and dumping soil; the inner side of the core pipe of the second power drilling tool is provided with an internal thread structure, the internal thread structure is matched with the external thread structure of the first power drilling tool to form threaded connection, the two structures form a relation between a nut and a screw rod, the second power drilling tool can reciprocate up and down/extrude at a single time in a pile hole soil extrusion area under the driving of a power mechanism equipped with the second power drilling tool, and the first power drilling tool (a central drilling tool) can be rotated to discharge soil for multiple times/single extrusion and extrusion expansion to be absorbed until the upper and lower compactness of the wall of the whole pile hole reaches relative balance.

Description

Thread fit type composite drilling tool and profile pile

Technical Field

The utility model belongs to the technical field of civil engineering technique and specifically relates to a screw-thread fit formula composite drilling tool and shaped pile are related to.

Background

In the soft foundation treatment of building structures or engineering such as bridges, ports, railways, highways, airports, water conservancy and hydropower facilities and the like, the foundation soil of the site soil to be treated can be generally divided into soft and weak site soil, medium and soft site soil, medium and hard site soil from shallow to deep according to the change rule of the equivalent shear wave velocity value; the foundation soil changes from shallow to deep, the compactness changes from loose to dense gradually, and the theory of rock-soil deposition is proved. According to the loose degree of the field soil and the distribution condition of each soil layer, the foundation soil can be simply divided into soil squeezing areas (soft field soil, medium soft field soil, wherein the water content is higher or saturated cohesive soil is excluded); and (4) a soil discharge area (except medium and hard field soil).

In order to improve the bearing capacity of foundation soil and reduce the settlement of foundation soil, a long spiral pressure-grouting pile-CFG pile construction method is generally adopted, in which a pile body is mainly used to replace the foundation soil. In recent years, new soil-squeezing methods such as screw piles (screw piles and shallow screw piles) and bidirectional screw soil-squeezing piles (SDS piles) have been developed. The soil-squeezing method is to improve equipment, increase dead weight and increase kinetic energy of a power mechanism so as to increase the torque of a special drilling tool. When the drilling tool is used for forming the hole, soil squeezing is mainly used, after the drilling tool drills and squeezes the soil to the designed depth, the drilling tool is lifted, and the concrete is pressed and poured to form the pile to the designed elevation, so the soil output is little, and the soil compactness around the pile is improved.

The two construction methods increase the bearing capacity of the foundation soil and reduce the settlement of the foundation soil in various stratums to different degrees. However, for complex and diversified foundation soil, drilling tools used by the two methods have single functions, the compactness is loose in shallow soft and medium soft field soil and is an extrudable soil area, the CFG pile method can only simply arrange and replace soil, and the friction resistance of the surrounding soil of the pile cannot be enhanced by the method, so that certain waste is caused; in deep medium-hard field soil, the soil quality is denser to be a soil discharge area, and the screw pile or SDS pile construction method further increases torque to squeeze and expand, so that drilling difficulty is caused, and work efficiency is influenced. If the compaction sandy soil is attempted to be squeezed and expanded, the compaction structure is broken, the strength is reduced, and even shear expansion damage is caused, so that the side friction resistance and the end resistance are reduced. The two geotechnical engineering methods have single function, cannot process foundation soil according to local conditions, cause certain cost waste and influence the bearing capacity exertion effect of a single pile. In order to solve the problems, according to the concept of the geotechnical engineering method, loose soil is suitable for extrusion during foundation treatment, dense soil is suitable for discharge, and the utility model is urgently needed. However, the extrusion-dumping composite drilling tool has the defects that: the soil squeezing gradient is suddenly changed (the blade segments of the soil squeezing and discharging spiral are relatively short), soil squeezing can be carried out while soil rotating and discharging in a close range, the contraposition of the pine needles is relatively poor due to density avoidance, and the effect of relatively balancing the compactness of the wall of the whole pile hole is poor; the soil squeezing ratio gradient is gradually changed (the blade segments of the screw for squeezing and discharging soil are relatively longer), the transfer distance of the rotary discharging soil is relatively far, and the soil squeezing effect is affected. In order to avoid the poor effect of the combined soil squeezing and discharging drilling tool, a brand-new generalized combined soil squeezing and discharging drilling tool is researched and developed.

The information disclosed in this background section is only for enhancement of understanding of the general background of the invention and should not be taken as an acknowledgement or any form of suggestion that this information constitutes prior art already known to a person skilled in the art.

SUMMERY OF THE UTILITY MODEL

An object of the utility model is to provide a screw-thread fit formula composite drilling tool and type stake to solve the technical problem who exists among the prior art.

In order to achieve the above purpose, the utility model adopts the following technical scheme:

in a first aspect, the utility model provides a screw-thread fit formula composite drilling tool, it includes: a first power drill and a second power drill;

the first power drilling tool is provided with a first power mechanism, the first power mechanism can independently drive the first power drilling tool to rotate, an external thread structure is arranged on the outer side of a core tube of a drilling tool main body of the first power drilling tool, and the external thread structure is used as a helical blade of the first power drilling tool;

the second power drilling tool is provided with a second power mechanism, the second power mechanism can independently drive the second power drilling tool to rotate, the second power drilling tool is sleeved on the first power drilling tool, an internal thread structure is arranged on the inner side of a core tube of a drilling tool main body of the second power drilling tool, the internal thread structure is matched with the external thread structure to form threaded connection, and the second power drilling tool can reciprocate up and down/rotate once in a pile hole under the driving of the second power drilling tool provided with the power mechanism, so that the soil can be continuously rotated and discharged by the first power drilling tool and is squeezed and expanded for many times/single time to be consumed; the second power drilling tool is composed of a drilling tool main body with an earth extrusion and displacement compound function, the outer diameter of a central core pipe of the drilling tool main body with the earth extrusion and displacement compound function is gradually increased from bottom to top and is changed according to a preset earth extrusion ratio, the earth extrusion ratio is defined as the ratio of the outer diameter of the central core pipe to the diameter of the drilling tool main body, and the width of helical blades of the drilling tool main body is gradually reduced from bottom to top so that the outer profiles of all the helical blades are distributed in an equal diameter mode.

As a further aspect, the first power drill includes: the device comprises a first power head, a central drilling tool and a first lifting device; the first power head is arranged at the upper end of the central drilling tool and used for driving the central drilling tool to rotate around the central line of the central drilling tool; the first lifting device is arranged at the lower end of the first power head and used for driving the second power drilling tool to lift; and an external thread structure is arranged on the outer side of the central core pipe of the central drilling tool and is used as a helical blade of the central drilling tool.

As a further aspect, the first power drill further includes: an upper limiting device; the upper limiting device is arranged at the lower end of the first power head.

As a further aspect, the second power drill includes: the second power head, the middle sleeve drilling tool and the helical blade; the second power head is arranged at the upper end of the middle sleeve drilling tool and used for driving the middle sleeve drilling tool to rotate around the center line of the middle sleeve drilling tool, and the second power head is connected with the first lifting device; an internal thread structure is arranged on the inner side of a core pipe of the middle sleeve drilling tool, and the middle sleeve drilling tool is sleeved on the central drilling tool, so that the internal thread structure is matched with the external thread structure to form threaded connection; the middle sleeve drilling tool is composed of a drilling tool main body which mainly extrudes soil and has a soil extrusion and removal combined function. The helical blade is arranged on the middle sleeve drilling tool.

As a further technical scheme, the second power drilling tool is provided with drill teeth below a middle core tube of the middle sleeve drilling tool, and the inner sides of the drill teeth are provided with internal thread structures matched with the external thread structures.

As a further technical scheme, the number of the drill teeth is one or more, and a plurality of the drill teeth are distributed at equal intervals.

As a further technical solution, the second power drill further includes: and the pressurizing device is arranged on the second power head.

As a further technical solution, the power mechanism includes: electromechanical/hydraulic drive.

In a second aspect, the present invention provides a screw-fit type composite drilling tool with the profile pile of preparation, include: a main body pile body;

the main body pile body is provided with an inverted step-shaped body;

the lower pile body of the main pile body is provided with a thread structure;

the inverted circular truncated cone generating line extension line of the inverted circular stepped profile and the included angle range of the central axis of the main pile body are as follows: 5 to 90 degrees.

In a third aspect, the present invention provides a method for preparing a profile pile according to the thread-fitting type composite drill, comprising:

according to the requirement of the stratum on a construction method, the first power drilling tool and the second power drilling tool respectively drill to respective designed depths, so that an inverted round step type drilling hole can be formed; in the drilling process of each drilling tool, the middle sleeve drilling tool performs reciprocating up and down/single rotary extrusion in a pile hole soil extrusion area, and the rotary dumping/single extrusion and expansion of the first power drilling tool are absorbed for multiple times until the upper and lower compactness of the wall of the whole pile hole is relatively balanced; and starting a concrete pump to press and pour concrete, sequentially lifting the first power drilling tool and the second power drilling tool while pressing and pouring the concrete, synchronously lifting the bottom ends of the power drilling tools after being aligned in sequence until the elevation of the orifice is mentioned, and simultaneously pressing and pouring the concrete to form the pile to the designed elevation, thereby realizing one-time completion of hole forming and concrete pressing and pouring of the pile.

Adopt above-mentioned technical scheme, the utility model discloses following beneficial effect has:

the utility model provides a screw-thread fit formula composite drilling tool, second power drilling tool suit are equipped with a power unit respectively on first power drilling tool, first power drilling tool and second power drilling tool. The spiral blade on the outer side of the core tube of the first power drilling tool is in a screw rod external thread structure (external thread structure); the inner side of the central core pipe of the second power drilling tool is provided with an inner screw structure, the inner screw structure and the inner screw structure form a nut and screw rod relation, the second power drilling tool can do reciprocating up and down/single rotary extrusion in a pile hole soil extrusion area under the driving of respective power mechanisms, and soil on the first power drilling tool (central drilling tool) is sequentially arranged in a rotary mode for multiple times/single extrusion and expansion to be absorbed until the upper and lower compactness of the wall of the whole pile hole is relatively balanced. The power mechanism is used for independently driving the corresponding drilling tools to rotate, when the composite drilling tool is constructed, each drilling tool is converted into an active driving mode from a traditional linkage mode, soil squeezing and soil discharging are simultaneously carried out, pore forming and concrete pressure filling pile forming can be completed at one time, the automation degree is high, and the work efficiency is improved; the pile body is reasonably changed in diameter, and the proper construction method further improves the bearing capacity of a single pile, reduces the settlement amount and further reduces the engineering cost; the comprehensive factors shorten the construction period; the technology has strong adaptability and is beneficial to popularization and application.

The utility model provides a type stake according to compound drilling tool of screw-thread fit formula preparation, its bearing capacity not only includes the stake side frictional resistance and the stake end load of traditional pile body, radius platform inclined plane of radius step type body moreover can be decomposed into the tangential force and the normal force on round platform inclined plane to the perpendicular decurrent power of part, stake week soil forms passive compressive stress state and crowded state that expands, has increased stake week frictional resistance, has improved the bearing capacity of single pile, can reduce the settlement volume. The bearing capacity of the shallow part inverted platform part of the pile can be calculated by a shallow foundation bearing capacity formula of a Taisha foundation (Terzaghi). Simultaneously the utility model discloses a provide for solving the bad effect that crowded combined drilling tool earth work method defect caused, aim at provides a generalized crowded combined drilling tool that arranges soil that is used for compound foundation pile or pile foundation pile. Through the composite drilling tool superposition and sleeving combined construction, soil squeezing and soil discharging are carried out simultaneously, but mutual cooperative support is realized, the middle sleeve drilling tool can be used for reciprocating up and down/single rotary squeezing in a pile hole soil squeezing area, soil on the central drilling tool is continuously and rotatably discharged is squeezed and expanded for multiple times/single time to be absorbed until the upper and lower compactness of the wall of the whole pile hole is relatively balanced, hole forming and concrete pressure filling pile forming can be completed at one time, the automation degree is high, and the work efficiency is improved; the pile body is reasonably changed in diameter, and the proper construction method further improves the bearing capacity of a single pile, reduces the settlement amount and further reduces the engineering cost; the comprehensive factors shorten the construction period.

The utility model provides a preparation method, according to the requirement of stratum to geotechnical engineering method, a first power drilling tool and a second power drilling tool respectively drill to respective designed depth, thereby forming a round step-shaped drilling hole; during the drilling process of each drilling tool, the middle sleeve drilling tool can perform reciprocating/single rotary extrusion up and down in the pile hole soil extrusion area, and the soil on the central drilling tool is continuously and rotatably arranged to be absorbed through multiple/single extrusion and expansion until the upper and lower compactness of the wall of the whole pile hole is relatively balanced. Starting the concrete pump, starting to press-pour the concrete, sequentially lifting the first power drilling tool and the second power drilling tool while pressing and pouring the concrete (lifting the first power drilling tool by adopting a synchronous technology in a reverse rotation manner until the drill bit end is aligned with the bottom end of the middle sleeve drilling tool and then finishing the synchronous technology in the reverse rotation manner), sequentially aligning the bottom ends of the power drilling tools and then synchronously lifting the bottom ends of the power drilling tools until the elevation of the orifice is mentioned, simultaneously pressing and pouring the concrete to the designed elevation, and realizing one-time completion of hole forming and pressing and pouring of the concrete to form the pile with the structure and the function.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the embodiments or the technical solutions in the prior art will be briefly described below, and it is obvious that the drawings in the following description are some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to these drawings without creative efforts.

Fig. 1 is a schematic structural diagram of an initial state of a thread-fit type composite drilling tool according to an embodiment of the present invention;

fig. 2 is a schematic structural diagram of a drilling state of the thread fit type composite drilling tool according to an embodiment of the present invention;

fig. 3 is a schematic structural diagram of a first power drill according to an embodiment of the present invention;

fig. 4 is a schematic front structural view of a first power head provided in an embodiment of the present invention;

fig. 5 is a schematic structural diagram of a second power drill according to an embodiment of the present invention;

fig. 6 is a schematic front structural view of a second power head provided in an embodiment of the present invention;

fig. 7 is a schematic view illustrating a working state of a drilling tool of the drilling machine aligned with a pile position according to an embodiment of the present invention;

FIG. 8 is a schematic view of an embodiment of the present invention illustrating a working state of a first power drill of a drilling machine assisting a second power drill to drill synchronously;

fig. 9 is a schematic view of a second power drill of the drilling machine according to the embodiment of the present invention, which is operated in a working state in which the second power drill is assisted by the first power drill to reach a preset pile depth;

fig. 10 is a schematic view illustrating a working state in which a second power drill of the drilling machine provided by the embodiment of the present invention is reversely rotated and lifted to a standard height of a pile hole;

fig. 11 is a schematic view illustrating a working state in which a first power drill and a second power drill of the drilling machine provided by the embodiment of the present invention synchronously drill to the depth of a respective preset pile;

fig. 12 is a schematic view illustrating a working state in which the first power drill is reversely rotated and lifted to be flush with the bottom end of the second power drill when the concrete pump is used for grouting concrete;

fig. 13 is a schematic view of a working state in which the concrete pump is used for grouting concrete and simultaneously and synchronously lifting the first power drill and the second power drill to the height of the pile hole;

fig. 14 is a schematic view illustrating the working state of the drilling tool of the drilling machine aligned with the pile position according to the embodiment of the present invention;

FIG. 15 is a schematic view of a working state of a first power drill of the drilling machine according to the embodiment of the present invention;

fig. 16 is a schematic view illustrating a working state of a second power drill of the drilling machine according to the embodiment of the present invention, which is driven by the first power drill to a preset pile depth with the assistance of rotary dumping;

fig. 17 is a schematic view of a working state in which a second power drill of the drilling machine provided by the embodiment of the present invention is reversely rotated and lifted to a standard height of a pile hole;

fig. 18 is a schematic view of the working state of the drilling machine according to the embodiment of the present invention, in which the first power drill and the second power drill synchronously drill to the depth of the respective pre-set piles;

fig. 19 is a schematic view showing a working state in which the first power drill is reversely rotated and lifted to be flush with the bottom end of the second power drill when the concrete pump is used for grouting concrete;

fig. 20 is a schematic view of a working state in which a first power drill and a second power drill are simultaneously and synchronously lifted to a standard height of a pile hole by grouting concrete with a concrete pump provided in an embodiment of the present invention;

fig. 21 is a schematic view of a first profile pile according to an embodiment of the present invention;

fig. 22 is a schematic view of a second profile pile according to an embodiment of the present invention.

Icon: 1-a first power drill; 2-a second power drill; 4-reducing threaded pile; 5-concrete pump; 11-a first power head; 12-a central drilling tool; 13-an upper lifting device; 14-upper limiting means; 21-a second power head; 22-intermediate sleeve drill; 24-a pressurizing device; 41-main body pile body; 42-a rounded step profile; 121-external thread structure; 221-internal thread construction.

Detailed Description

The technical solution of the present invention will be described clearly and completely with reference to the accompanying drawings, and obviously, the described embodiments are some, but not all embodiments of the present invention. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative work belong to the protection scope of the present invention.

The following detailed description of the embodiments of the present invention will be made with reference to the accompanying drawings. It is to be understood that the description of the embodiments herein is for purposes of illustration and explanation only and is not intended to limit the invention.

Example one

Referring to fig. 1 to 6, the present embodiment provides a thread-fit type composite drill, which includes: a first power drill 1 and a second power drill 2; the second power drilling tool 2 is sleeved on the first power drilling tool 1, the first power drilling tool 1 and the second power drilling tool 2 are respectively provided with a power mechanism, and the power mechanisms can independently drive the corresponding drilling tools to rotate; the first power drill 1 is provided with an external thread structure 121 on the outer side of a core tube of a drill body, and the external thread structure 121 is used as a helical blade of the first power drill 1; the second power drilling tool 2 is provided with an internal thread structure 221 on the inner side of a core tube of a drilling tool main body, the internal thread structure 221 is matched with the external thread structure 121 to form threaded connection, and the second power drilling tool 2 can reciprocate up and down/rotate and extrude at a single time in a pile hole soil extrusion area under the driving of a power mechanism arranged on the second power drilling tool 2, so that the continuous rotary soil discharge of the first power drilling tool 1 is extruded and expanded for multiple times/single time to be absorbed; the second power drilling tool 2 is composed of a drilling tool main body with an earth extrusion and displacement compound function, the outer diameter of a central core pipe of the drilling tool main body with the earth extrusion and displacement compound function is gradually increased from bottom to top and is changed according to a preset earth extrusion ratio, the earth extrusion ratio is defined as the ratio of the outer diameter of the central core pipe to the diameter of the drilling tool main body (the diameter of the drilling tool main body is always a certain value), and the width of helical blades of the drilling tool main body is gradually reduced from bottom to top so that the outer contours of all the helical blades are distributed in an equal diameter (the outer contour size of the helical blades is the diameter of the drilling tool main body).

It is worth mentioning that:

firstly, for a drilling tool main body which mainly extrudes soil and has a soil extrusion and dumping composite function, the ratio of the outer diameter of a central core pipe to the diameter of the drilling tool main body (which can be understood as the maximum diameter of the drilling tool main body) is gradually increased from bottom to top, wherein the ratio is defined as the soil extrusion ratio of a soil extrusion drilling tool section, the numerical range of the soil extrusion ratio of the soil extrusion drilling tool is 0.6-1.0, and the soil extrusion ratio of the soil extrusion drilling tool is gradually changed from bottom to top. Preferably, the ratio of the outer diameter of the central core pipe to the diameter of the drilling tool is gradually increased from bottom to top, the minimum soil squeezing ratio is not less than 0.6, (the soil squeezing ratio of the drilling tool is not less than 0.6, the drilling tool mainly squeezes soil.) the soil squeezing ratio of the soil squeezing drilling tool is gradually increased from bottom to top, and the maximum soil squeezing ratio is 1.0 (namely the light rod section). The thickness of the blade meets the strength requirement, the width of the blade is gradually reduced from bottom to top until the blade is not changed into a polished rod section, a proper screw diameter ratio is selected to control the pitch width, the blade is suitable for rotating and discharging soil, and the outer diameter of the central core pipe is thickened from bottom to top according to a certain gradient. The soil-squeezing ratio of the drilling tool is 1.0, and the polished rod section has the functions of prolonging the soil-squeezing drilling tool, supporting the side wall of the hole and preventing the hole wall from loosening. The drilling tool mainly extrudes soil when forming holes.

Secondly, for the drilling tool main body which mainly uses the soil discharging and has the soil squeezing and discharging composite function, the ratio of the outer diameter of the central core pipe to the diameter of the drilling tool main body (which can be understood as the maximum diameter of the drilling tool main body) is gradually increased from bottom to top, the ratio is defined as the soil squeezing ratio, and the numerical range of the soil squeezing ratio is less than 0.6; wherein, the soil squeezing ratio of the soil discharging drilling tool gradually changes from small to large from bottom to top or takes a certain value. Preferably, the ratio of the outer diameter of the central core pipe to the diameter of the drilling tool is gradually increased from bottom to top, and the maximum soil extrusion ratio is less than 0.6. (note: the soil-discharging drill is used when the soil-squeezing ratio of the drill is less than 0.6) the soil-squeezing ratio of the soil-discharging drill gradually changes from small to large from bottom to top, and can also be a certain value. The width of the blade gradually changes from large to small from bottom to top, and can also be a fixed value. The thickness of the blade meets the strength requirement, and the pitch width is controlled by selecting a proper screw diameter ratio to be suitable for soil rotation and upward discharging. The outer diameter of the central core tube is increased from bottom to top by a certain gradient, or a certain value. The hole forming of the drilling tool is mainly realized by dumping.

Thirdly, for the drilling tool main body with the composite function of extruding and dumping soil, the outer diameter of the central core tube is gradually increased from bottom to top and is changed according to a preset soil extruding ratio, the soil extruding ratio is defined as the ratio of the outer diameter of the central core tube to the diameter of the drilling tool main body (the diameter of the drilling tool main body is always a certain value), and the width of the helical blades of the drilling tool main body is gradually reduced from bottom to top so that the outer contours of all the helical blades are distributed in an equal diameter (the size of the outer contour of the helical blades is the diameter of the drilling tool main body). The drilling tool main body with the soil squeezing and discharging composite function can be divided into a soil squeezing drilling tool section and a soil discharging drilling tool section, and the soil squeezing drilling tool section and the soil discharging drilling tool section are integrally connected from top to bottom to form the drilling tool main body with the soil squeezing and discharging composite function. Certainly, the numerical range of the soil squeezing ratio of the soil squeezing drilling tool section is 0.6-1.0, and the soil squeezing ratio of the soil squeezing drilling tool gradually changes from small to large from bottom to top; the numerical range of the soil extrusion ratio of the soil discharge drilling tool section is less than 0.6; wherein, the soil squeezing ratio of the soil discharging drilling tool gradually changes from small to large from bottom to top or takes a certain value.

Furthermore, it is worth mentioning that the design of the helical blade of the drill body can be flexibly set by those skilled in the art according to the actual needs. Wherein the broad meaning is to be understood herein. For example: the helical blades of the inverted circular truncated cone structure corresponding to the lowermost end of the drilling tool body do not need to meet the rule that the outer contour is in equal-diameter distribution, and because the inverted circular truncated cone structure can be approximately used as a drill bit, the helical blades arranged on the drill bit do not need to be arranged according to the requirement that the outer contour is in equal-diameter distribution. Of course, the parts above the frustum structure can meet the rule that the outer contour of the helical blade is distributed in the same diameter.

Further, it is worth mentioning that the specific dimensions of the external thread structure 121 are not limited. Preferably, to ensure that the external thread structure 121 can function well as a helical blade. For example: the diameter of the central drilling tool 12 (first power drill 1) is 400mm, and the pitch and thread structure of the external thread structure 121 are as follows: the pitch between the external thread structures 121 (the distance between adjacent external threads) is 350-: 0.88-1.0. For example: the thread height of the external thread structure 121 (the distance between the outer edge of the external thread structure 121 and the surface of the core tube) is 50mm, and the soil extrusion ratio: 0.75. for example: the inner side of the thread thickness of the external thread structure 121 is 100mm, and the outer side of the thread thickness of the external thread structure 121 is 50 mm.

In the present embodiment, preferably, the first power drill 1 includes: a first power head 11, a central drilling tool 12 and a first lifting device; the first power head 11 is arranged at the upper end of the central drilling tool 12 and is used for driving the central drilling tool 12 to rotate around the central line of the central drilling tool; the first lifting device is arranged at the lower end of the first power head 11 and is used for driving the second power drilling tool 2 to perform lifting action; an external thread structure 121 is arranged on the outer side of the core tube of the central drilling tool 12, and the external thread structure 121 is used as a helical blade of the central drilling tool 12.

There are various ways for the upper lifting means 13.

For example: the upper lifting device 13 includes: and the winch is arranged at the lower end of the first power head 11 (or arranged on the operating platform of the drilling machine, the traction rope is additionally provided with a pulley block through the forehead of the drilling machine to be connected with the second power drilling tool 2), and the traction rope of the winch is connected with the second power drilling tool 2 (preferably the second power head 21).

Another example is: the upper lifting device 13 includes: and the telescopic cylinder (oil cylinder) is arranged at the lower end of the first power head 11, and a piston rod of the telescopic cylinder is connected with the second power drilling tool 2 (preferably, the second power head 21).

In this embodiment, preferably, the first power drill 1 further includes: an upper limit device 14; the upper limiting device 14 is arranged at the lower end of the first power head 11. The upper limiting device 14 is arranged at the lower end of the first power head 11. There are many ways for the upper limiting device 14. For example: the upper limiting device 14 may be a rigid connecting rod, the length of which is flexibly set according to the actual situation. The telescopic connecting rod can also be used, and the length of the telescopic connecting rod can be adjusted freely according to requirements.

Preferably, the second power drill 2 comprises: a second power head 21, an intermediate sleeve drill 22 and a helical blade; the second power head 21 is arranged at the upper end of the middle sleeve drilling tool 22 and used for driving the middle sleeve drilling tool 22 to rotate around the central line of the middle sleeve drilling tool, and the second power head 21 is connected with the first lifting device; an internal thread structure 221 is arranged on the inner side of a core tube of the middle sleeve drilling tool 22, and the middle sleeve drilling tool 22 is sleeved on the central drilling tool 12, so that the internal thread structure 221 and the external thread structure 121 are matched to form threaded connection; the middle sleeve drill 22 is formed by a drill main body mainly used for squeezing soil and having a combined function of squeezing and removing soil (it can be understood that a soil squeezing drill section is mainly used, and a soil removing drill section is auxiliary).

Preferably, the second power drill 2 is provided with drill teeth below the core tube of the middle casing drill 22, and the inner sides of the drill teeth are provided with internal thread structures 221 matched with the external thread structures 121.

Preferably, the number of the drill teeth is one or more, and a plurality of the drill teeth are distributed at equal intervals. Preferably, this embodiment further includes: a pressurizing device 24, wherein the pressurizing device 24 is arranged on the second power drilling tool 2.

Of course, the pressure device 24 can be flexibly arranged according to the characteristics of the power mechanism, geological conditions and design requirements, and preferably, the pressure device 24 can be a winch arranged on the drilling platform, and a traction rope of the winch is connected with the second power drilling tool 2 (the power head of the second power drilling tool 2) through a guide wheel. The pressurizing device 24 may also be a hydraulic cylinder, the cylinder barrel of the hydraulic cylinder is fixedly arranged at a suitable position of the drilling tower, and the top end of the piston rod of the hydraulic cylinder is connected with the second power drilling tool 2 (the power head of the second power drilling tool 2). The pressurizing device can also be in a mode of driving a chain by a speed reducer, the speed reducer is arranged on a drilling rig platform or a drilling tower, one end of the chain is connected to a gear of the speed reducer, the other end of the chain is fixed on the power head of the second power drilling tool (2), or the chain is connected with the second power drilling tool (the power head of the second power drilling tool (2)) through a movable pulley (gear), and the other end of the chain is fixed at a proper position of the drilling rig.

Preferably, the power mechanism includes: electromechanical/hydraulic drive.

For example: the first powerhead includes: the power box, the motor, the speed reducer and the concrete conveying pipe; the power box is provided with a hoisting pulley block, a sliding shoe and a pressurizing pulley block, the speed reducer is connected with the motor/motor, the motor/motor and the speed reducer are installed on the power box, the concrete conveying pipe is connected with the hollow central shaft of the speed reducer in a rotatable and sealed mode, the hollow central shaft of the speed reducer is connected with the central drilling tool through the output flange, and after the speed of the motor rotates at a high speed and is reduced through the speed reducer, the power input of the speed reducer is provided for the central drilling tool. Wherein the concrete

The conveying pipe, the hollow central shaft of the speed reducer and the hollow channel of the central drilling tool are communicated.

For example: the second power head includes: power boxes, motors/motors and reducers; the power box is provided with a hoisting pulley block, a sliding shoe and a pressurizing pulley block, the speed reducer is connected with the motor/motor, the motor/motor and the speed reducer are installed on the power box, a central shaft of the speed reducer is connected with the middle sleeve drilling tool through an output flange, and after the speed of the motor is reduced through the speed reducer, the power input of the speed reducer is provided for the middle sleeve drilling tool. Wherein the concrete

Of course, there may be other specific configurations for each power head, and no examples are given here.

Example two

As shown in fig. 7 to 13 and 14 to 20, the second embodiment provides two preparation methods for preparing the pile 4 according to different site soil conditions of the thread fit type composite drilling tool, which include: according to the requirement of the stratum on a construction method, the first power drilling tool 1 and the second power drilling tool 2 respectively drill to respective designed depths, so that an inverted step-shaped drilling hole can be formed; in the drilling process of each drilling tool, the middle sleeve drilling tool 22 performs reciprocating up and down/single rotary extrusion in a pile hole soil extrusion area, and the rotary dumping/single extrusion and expansion of the first power drilling tool 1 are absorbed for multiple times until the upper and lower compactness of the wall of the whole pile hole is relatively balanced; and starting the concrete pump 5 to press-pour the concrete, sequentially lifting the first power drilling tool 1 and the second power drilling tool 2 while pressing and pouring the concrete, synchronously lifting the bottom ends of the power drilling tools after being aligned in sequence until the elevation of the orifice is mentioned, and simultaneously pressing and pouring the concrete to form the pile to the designed elevation, thereby realizing one-time hole forming and concrete pressing and pouring pile forming.

In the treatment of building structures or soft foundations such as railways, highways and the like, the foundation soil of the site soil to be treated can be generally divided into soft and weak site soil (the average shear wave velocity of the soil layer is less than or equal to 140m/s), medium and soft site soil (the average shear wave velocity of the soil layer is more than 140m/s and less than or equal to 250m/s), medium and hard site soil (the average shear wave velocity of the soil layer is more than 250m/s and less than or equal to 500m/s) and hard site soil (the shear wave velocity of the soil layer is more than 500m/s) from shallow to deep according to the change rule of the.

According to the soft and hard degree of field soil and the distribution condition of each soil layer in the depth range of a pile body, the loose-extrusion and close-packed geotechnical engineering method is combined, and the pile forming effect matched with the thread fit type composite drilling tool combination form is divided into two types: firstly, the pile is basically not unearthed; and secondly, forming part of the pile and unearthing.

Firstly, the pile is basically not excavated, and is suitable for the stratum conditions: the site soil in the depth of the pile body is soft and medium soft site soil (or the medium hard site soil at the lower part of the pile body occupies little or partial proportion);

the site soil within the depth range of the pile body is soft and medium soft site soil, and the construction method adopts soil extrusion; the matching of the thread matching type composite drilling tool is the leading one of the soil squeezing section drilling tools, the matching of the soil discharging section drilling tools is adopted, and the soil discharging is also the principle of soil squeezing service.

The soil squeezing ratio of the central drilling tool 12 is not less than 0.6 and less than 1.0 and is a certain value, the screw diameter ratio is suitable for soil discharging and is beneficial to soil squeezing, the screw pitch is equidistant, the effective length is not less than the soil thickness of a treatment site, and the specific value is finally determined according to the design requirement and the stratum condition;

the middle sleeve drilling tool 22 is a soil-squeezing drilling tool, a soil-squeezing-and-dumping drilling tool which mainly squeezes soil is adopted, the soil-squeezing ratio is mainly the soil-squeezing section which is not less than 0.6 and not more than 1.0, the soil-squeezing ratio is gradually changed from bottom to top to 1.0, the length of the soil-squeezing section or the change degree of the soil-squeezing ratio is determined according to the compactness of soil in soft and medium soft fields and the output torque of a power mechanism of the drilling machine, and the drilling tool with the soil-squeezing ratio of 1.0 is a polished rod section. The screw diameter ratio is suitable for extruding soil, and the screw pitch can be in the same diameter, preferably gradually changed from bottom to top and from large to small. The effective length of the middle sleeve drilling tool is generally not more than half of the thickness of the soil of a treatment site, and the specific value is finally determined according to the design requirement and the stratum condition.

The function of the central drilling tool 12 is determined by the drilling form, and the working efficiency of the construction method is determined according to the stratum compactness condition, and a reasonable drilling form is adopted. And for soft field soil and medium soft field soil in the range of the pile body, combining the soil absorption capacity and design requirements of a medium power drilling tool and a lower power drilling tool, controlling the rotary soil discharge amount, and then adopting screw threads to extrude soil to drill to reach the designed depth or drilling into the medium hard field soil for a plurality of drill stops.

The middle sleeve drill 22 is a soil-squeezing and dumping drill mainly for squeezing soil;

the soil squeezing area is as follows: soft field soil, medium soft field soil;

during pore-forming, the bottom ends of the middle sleeve drilling tool 22 and the central drilling tool 12 are drilled in a follow-up mode, a slow-speed drilling mode is adopted firstly, the drilling tools are screwed and drilled in a soil squeezing area in advance, after the polished rod section of the middle sleeve drilling tool 22 is subjected to hole sealing, the central drilling tool 12 is drilled in a soil discharging mode, soil in the deep part of a hole is discharged to the upper part of the hole in a rotating mode, the middle sleeve drilling tool 22 reciprocates/is extruded in the soil squeezing area of the pile hole in a single rotating mode from top to bottom, and the soil on the central drilling tool 12 is sequentially discharged in a rotating mode for multiple times/single times, extruded and expanded to be absorbed until the upper and. When the power center drilling tool drills to the designed depth or drills into a plurality of medium-hard field soil, the middle sleeve drilling tool 22 drills to the designed depth in the soil squeezing area in the soil squeezing mode at the same time, then the drilling is stopped, concrete is grouted into the middle core pipe while the power drilling tools are sequentially lifted (when the first power drilling tool 1 is lifted, the synchronous technology is adopted for reverse lifting, the synchronous technology is finished for reverse lifting until the drill bit end is flush with the bottom end of the middle sleeve drilling tool 22), the bottom ends of the two drilling tools are sequentially flush and then synchronously lifted until the orifice elevation is mentioned, and meanwhile the concrete is also grouted to the designed elevation by pressure to form the pile.

After the hole-forming pouring pile is formed, the soil in the soil-squeezing area in the pile hole is squeezed and expanded, a proper amount of rotary dumping soil is absorbed in the wall of the soil-squeezing area, the soil in the middle lower part of the pile hole is successively and rotatably dumped to the upper soil-squeezing area by the central drilling tool 12, and the soil-squeezing section is repeatedly/singly and gradually rotated, squeezed and expanded and absorbed in the wall of the pile hole, so that the side frictional resistance of the wall of the pile hole is enhanced.

The conditions of no unearthing after pile forming are as follows: the second power drilling tool 2 has the capabilities of soil squeezing and soil absorbing (including torque power of a power head and pressure), the range and the depth of a soil squeezing area, the soil compactness of the part and the soil discharging amount of the upper power drilling tool, and the conditions are matched with each other to form a hole normally and form a pile without soil discharging.

And the field soil in the depth of the pile body is soft and medium soft field soil (or the medium hard field soil at the lower part of the pile body occupies little or partial proportion), the torque capacity of the second power drilling tool is not enough to absorb the soil discharge amount of the upper power drilling tool in the designed soil squeezing range and depth, and the power drilling tool is used for drilling in a thread soil squeezing mode until the designed depth is reached after the soil compactness in the range and the depth of the soil squeezing area reaches the design requirement.

Secondly, the pile forming part is unearthed, and the method is suitable for the stratum condition:

the upper part of the field soil in the depth of the pile body is soft and medium soft field soil, and the middle part and the lower part are medium hard field soil (the medium hard field soil is distributed in a large proportion or the majority is the medium hard field soil).

The site soil within the depth range of the pile body is soft and medium soft site soil, and the construction method adopts soil extrusion; the construction method adopts the soil removal for medium-hard field soil.

The soil extrusion ratio of the central drilling tool 12 is not less than 0.6 and less than 1.0 and is a certain value, the screw diameter ratio is suitable for discharging soil, the screw pitch is equidistant, the effective length is not less than the soil thickness of a treatment site, and the specific value is finally determined according to the design requirement and the stratum condition.

The middle sleeve drilling tool 22 adopts a soil squeezing and dumping drilling tool which is mainly used for squeezing soil, the soil squeezing ratio is mainly a soil squeezing section which is not less than 0.6 and not more than 1.0, the soil squeezing ratio is gradually changed from bottom to top to 1.0 from small to large, the length of the soil squeezing and dumping section or the change degree of the soil squeezing ratio is determined according to the soil compactness of weak and medium-soft sites to be processed and the output torque of a power mechanism of the drilling machine, and the soil squeezing ratio of the drilling tool is 1.0 and is a polished rod section. The screw diameter ratio is suitable for extruding soil, the screw pitch can be equidistant, and the screw pitch is gradually changed from bottom to top and from large to small. The effective length of the middle sleeve drilling tool is generally slightly larger than the thickness of the soil in the soft and medium-soft field, and the specific value is finally determined according to the design requirement and the stratum condition.

Drilling by the central drilling tool in a dumping mode;

the soil squeezing area is as follows: soft field soil, medium soft field soil;

the soil discharge area is as follows: medium hard field soil.

When the hole is formed, the central drilling tool 12 rotationally discharges part of the redundant pile hole soil according to the variable diameter geometric dimension of the upper part of the pile and the soil absorption capacity of the drilling tool of the middle sleeve drilling tool 22 in advance, after the pile hole is drilled at a plurality of depths, the middle sleeve drilling tool 22 follows,

the central drilling tool 12 drills in a soil discharging mode, soil in the deep part of the hole is discharged to the upper part of the hole in a rotary mode, the middle sleeve drilling tool 22 reciprocates/is extruded in a rotary mode from top to bottom in a pile hole soil extruding area in a single mode, and the soil on the central drilling tool 12 is extruded and expanded for multiple times/single times in a rotary mode sequentially to be absorbed until the upper and lower compactness of the wall of the whole pile hole is relatively balanced. When the power center drilling tool 12 reaches the designed depth in the soil discharge area, the middle sleeve drilling tool 22 drills to the designed depth in the soil squeezing area in a soil squeezing mode at the same time, then the drilling is stopped, concrete is poured into the middle core pipe in a medium pressure mode, the power drilling tools are sequentially lifted (when the first power drilling tool 1 is lifted, the synchronous technology is adopted for reverse lifting, the synchronous technology is finished for reverse lifting until the drill bit end is flush with the bottom end of the middle sleeve drilling tool 22), the bottom ends of the two drilling tools are sequentially flush and then are lifted synchronously until the orifice elevation is mentioned, and meanwhile, the concrete is also poured into the pile to the designed elevation in a pressure mode.

After the hole-forming pouring pile is formed by the squeezing and dumping drilling tool combination mainly by squeezing, the soil in the weak and medium-soft field in the pile hole is squeezed and squeezed, and a proper amount of rotary dumping soil is absorbed in the wall of the soil-squeezing area; the soil in the hard field in the lower part of the pile hole is rotationally discharged to the soil squeezing area in the upper part by the central drilling tool 12, and the soil squeezing and discharging section is repeatedly/singly and gradually rotationally discharged, squeezed and expanded in the wall of the pile hole, so that the side frictional resistance of the wall of the pile hole is enhanced.

The conditions of no unearthing after pile forming are as follows: the second power drilling tool 2 has the capabilities of soil squeezing and soil absorbing (including torque power of a power head and pressure), the range and the depth of a soil squeezing area, the soil compactness of the part and the soil discharging amount of the upper power drilling tool, and the conditions are matched with each other to form a hole normally and form a pile without soil discharging. The rotary soil discharge within the depth range of the soil squeezing area is squeezed for multiple times and squeezed to reach the maximum relative compactness, the soil discharge amount of a power drill cannot be completely absorbed, and only the redundant pile hole soil is discharged outside an orifice in a rotary manner in advance, and then the rotary soil discharge is absorbed by the soil squeezing area.

The field soil within the depth range of the pile body is mainly medium-hard field soil, the soft and medium-soft field soil on the upper part of the pile body accounts for little or part of the ratio, the diameter-changing condition and the depth of the upper part of the pile are determined according to the soil-squeezing and soil-absorbing capacity of a second drilling tool, the range of a soil-squeezing area, the soil compactness in the depth and the soil discharge amount of a first power drilling tool 1, and the redundant pile hole soil outside a discharge hole opening is calculated so as to ensure that the upper power drilling tool drills in a soil-discharge mode all the time to the designed depth.

For the field soil within the depth range of the pile body, the upper part of the pile body is soft and medium soft field soil, the lower part of the pile body is medium and hard field soil, the soft and hard field soil basically accounts for half and half, and according to the soil squeezing and soil absorbing capacity of the second power drilling tool 2, the soil squeezing area range, the soil compactness condition in the depth and the soil discharge amount of the first power drilling tool 1, the two effects of no soil or partial soil can be generated during pile forming construction according to different design requirements by combining the above conditions.

For the case of the variable diameter pile thread:

because the intermediate sleeve drilling tool 22 and the central drilling tool 12 rotate up and down to form a nut and screw rod relationship, in view of the pressure-grouting pile process requirements, the central drilling tool 12 must be synchronously reversed and lifted when lifting the pressure-grouting concrete to form a pile, and the synchronous technology reversal is finished until the drill bit end is flush with the bottom end of the intermediate sleeve drilling tool 22, so that the main body of the pile body formed by the central drilling tool 12 is provided with threads.

Because the function requirement and the internal structure condition of the middle sleeve drilling tool 22, the middle sleeve drilling tool 22 can only adopt an extrusion-based soil-discharging drilling tool to perform reciprocating extrusion up and down in a pile hole, so that the middle drilling tool forms a pile body main body without threads, and the first variable diameter pile body of the pile top has no threads.

EXAMPLE III

As shown in fig. 21 to 22, the present embodiment provides a profile pile (variable diameter threaded pile 4) prepared by the thread-fit type composite drill, including: a main body pile body 41; an inverted step-shaped body 42 is arranged on the main body pile body 41; the main pile body 41 is provided with a thread structure at the lower pile body; the extension line of the inverted circular truncated cone generatrix of the inverted circular step-shaped body 42 and the included angle range of the central axis of the main pile body 41 are as follows: 5 to 90 degrees.

Finally, it should be noted that: the above embodiments are only used to illustrate the technical solution of the present invention, and not to limit the same; although the present invention has been described in detail with reference to the foregoing embodiments, it should be understood by those skilled in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some or all of the technical features may be equivalently replaced; such modifications and substitutions do not depart from the spirit and scope of the present invention.

Claims

1. A thread-mating type composite drilling tool, comprising: a first power drilling tool and a second power drilling tool are coaxially sleeved in sequence;

the second power drilling tool is provided with a second power mechanism, the second power mechanism can independently drive the second power drilling tool to rotate, the second power drilling tool is sleeved on the first power drilling tool, an internal thread structure is arranged on the inner side of a core pipe of a drilling tool main body of the second power drilling tool, the internal thread structure is matched with the external thread structure to form threaded connection, and the second power drilling tool can reciprocate up and down/rotate once in a pile hole soil extrusion area under the driving of the second power drilling tool provided with the power mechanism, so that the rotary soil discharge of the first power drilling tool is absorbed by multiple/single extrusion and expansion; the second power drilling tool is composed of a drilling tool main body with an earth extrusion and displacement compound function, the outer diameter of a central core pipe of the drilling tool main body with the earth extrusion and displacement compound function is gradually increased from bottom to top and is changed according to a preset earth extrusion ratio, the earth extrusion ratio is defined as the ratio of the outer diameter of the central core pipe to the diameter of the drilling tool main body, and the width of helical blades of the drilling tool main body is gradually reduced from bottom to top so that the outer profiles of all the helical blades are distributed in an equal diameter mode.

2. The thread-fit composite drill according to claim 1, wherein the first power drill comprises: the device comprises a first power head, a central drilling tool and a first lifting device;

the first power head is arranged at the upper end of the central drilling tool and used for driving the central drilling tool to rotate around the central line of the central drilling tool; the first lifting device is arranged at the lower end of the first power head and used for driving the second power drilling tool to lift; and an external thread structure is arranged on the outer side of the central core pipe of the central drilling tool and is used as a helical blade of the central drilling tool.

3. The thread-fit composite drill of claim 2, wherein the first motor drill further comprises: an upper limiting device; the upper limiting device is arranged at the lower end of the first power head.

4. The thread-fit composite drill according to claim 2, wherein the second power drill comprises: the second power head, the middle sleeve drilling tool and the helical blade;

the second power head is arranged at the upper end of the middle sleeve drilling tool and used for driving the middle sleeve drilling tool to rotate around the center line of the middle sleeve drilling tool, and the second power head is connected with the first lifting device; an internal thread structure is arranged on the inner side of a core pipe of the middle sleeve drilling tool, and the middle sleeve drilling tool is sleeved on the central drilling tool, so that the internal thread structure is matched with the external thread structure to form threaded connection; the middle sleeve drilling tool is composed of a drilling tool main body which mainly extrudes soil and has a soil extrusion and removal combined function.

5. The thread-fit composite drilling tool according to claim 4, wherein the second power drilling tool is provided with drill teeth below the core tube of the middle sleeve drilling tool, and the inner side of the drill teeth is provided with an internal thread structure matched with the external thread structure.

6. The thread-fit composite drilling tool as claimed in claim 5, wherein the number of the drill teeth is one or more, and the plurality of drill teeth are equally spaced.

7. The thread-fit composite drill of claim 4, wherein the second motor further comprises: and the pressurizing device is arranged on the second power head.

8. The thread-fit composite drilling tool according to claim 1, wherein the power mechanism comprises: electromechanical/hydraulic drive.

9. A profile pile prepared by a thread-fit composite drill according to any one of claims 1 to 8, comprising: a main body pile body;

the main body pile body is provided with an inverted step-shaped body;

the lower pile body of the main pile body is provided with a thread structure;