CN221118470U - Drilling tool for construction of large-diameter multilayer mutual shearing stirring pile - Google Patents

Abstract

The utility model relates to the technical field of stirring drilling tools, in particular to a drilling tool for construction of a large-diameter multilayer mutual shearing stirring pile, which comprises an outer rod, an inner rod and at least two stirring wings; at least one inner rod pulp passage is arranged in the inner rod; at least one stirring wing is radially distributed on the outer side wall of the central shaft of the outer rod; at least one stirring wing is radially distributed on the outer side wall of the central shaft of the inner rod, the stirring wings positioned on the same layer rotate along with the outer rod in the same direction or rotate along with the inner rod in the same direction, at least one fixed connection point is arranged between the stirring wings and the rod piece rotating in the same direction, and when the stirring wings are simultaneously connected with the rod piece rotating in the opposite direction, the stirring wings are rotationally connected with the rod piece. The utility model has the advantages of solving the problems of limited stirring area, poor mutual shearing effect of stirring wings and the like caused by consistent track of the stirring wings, realizing larger-range soil disturbance, realizing consistent stirring time compared with the conventional stirring construction method, and achieving the effect of more fully and uniformly stirring.

Description

Drilling tool for construction of large-diameter multilayer mutual shearing stirring pile

Technical Field

The utility model relates to the technical field of stirring drilling tools, in particular to a drilling tool for construction of large-diameter multilayer mutual shearing stirring piles.

Background

As a main construction method in the technical field of foundation treatment engineering, the deep mixing pile technology has been widely applied to engineering construction fields including civil engineering, construction engineering, railway engineering, highway engineering, hydraulic engineering, municipal engineering, port engineering and the like since the 60 s of the last century. The deep mixing pile engineering technology adopts a single-shaft or multi-shaft mixing drilling machine to input curing agents such as cement and the like into the ground, and the curing agents and the soil are mixed by stirring, so that a series of physical and chemical reactions are generated between the curing agents and the soil, and pile bodies, wall bodies and blocks with high strength, good water stability and strong seepage resistance are generated. Therefore, the bearing capacity of the composite foundation, the bearing capacity of the stirring pile, the bearing capacity of the stiffening core composite pile and the bearing capacity of the SMW construction method pile are effectively improved, and the practical engineering problems of impervious force of the water-proof wall, sealing wall and sealing layer of polluted soil and toxic substance landfill sites and the like are solved.

The deep mixing pile engineering technology has the advantages of simple drilling rig equipment, high construction efficiency, low cost and the like, and has been widely applied to the civil construction field. However, when the conventional stirring pile construction drilling tool is designed, straight stirring blades are arranged on the central rod of the drilling tool to stir or a slurry spraying opening is arranged on the central rod of the drilling tool to spray slurry, the sprayed curing agent slurry and soil are uniformly mixed through the stirring blades to form a stirring pile with a certain diameter, when the diameter of a pile foundation is smaller, the stirring requirement can be met, but when the large-diameter and large-depth stirring pile is required to be used for construction in engineering, the stirring capability of the straight stirring blades is insufficient, the stirring effect is poor, in addition, the amount of the curing agent slurry required by a pile body in unit length is multiplied, the slurry around the central rod of the drilling tool is difficult to quickly reach all points of the section of the pile foundation, particularly the peripheral area through stirring disturbance of the soil, a large amount of the curing agent slurry can not be dispersed, the curing agent is gathered in part of the area, particularly the central area, the peripheral cement soil is finally caused to be far lower than the central cement soil strength even without strength, the whole strength of the curing soil is lower than the design value, and the serious engineering quality problems are often caused, and meanwhile, the large-power and large-flow-rate stirring pile is required, and the slurry pump is increased in cost. Therefore, when the stirring drilling tool designed by adopting the conventional slurry conveying channel and slurry spraying port is used for construction, the engineering quality and engineering safety risk are particularly remarkable, and the engineering cost is remarkably increased. The existing civil construction market needs to solve the technical problems of the engineering, and some conventional solutions mainly comprise: 1. the spraying pressure is increased, the slurry is sent to the outer side of the pile body by using jet flow, or the mixing amount of the cement slurry is increased, but the methods need additional equipment or material consumption, and the construction cost is increased; 2. the number of stirring blades is increased or the stirring time is increased by adopting a four-stirring two-spraying or multi-stirring multi-spraying process, so that the uniformity is improved to a certain extent, the construction efficiency is reduced, the stirring resistance is increased, the power of power head equipment and the strength requirement of a drill rod and drill bit are greatly improved, and the construction feasibility is influenced; therefore, the existing stirring pile construction drilling tool still has the problems of limited peripheral stirring capability and poor stirring effect.

Disclosure of utility model

The utility model aims to overcome the defects of the prior art and provide a drilling tool for construction of a large-diameter multi-layer shearing stirring pile, and solves the problems of limited peripheral stirring capacity, poor stirring effect and the like of the stirring pile by adopting a stirring wing design rotating along with an inner rod and an outer rod, and can realize shearing stirring with less stirring times than a conventional stirring construction method, namely, the effect of stirring uniformly, thereby greatly reducing the strength difference of the pile body of the stirring pile and greatly improving the overall strength, and the construction diameter of the stirring pile can reach 1500-3000 mm or even more by utilizing the structure.

The utility model aims at realizing the following technical scheme:

A drilling tool for construction of large-diameter multilayer mutual shearing stirring piles comprises an outer rod, an inner rod, at least two stirring wings and a plurality of digging wing plates; at least one inner rod pulp passage is arranged in the inner rod; the outer rod is rotatably connected to the inner rod; at least one stirring wing is radially distributed on the outer side wall of the central shaft of the outer rod; at least one stirring wing is radially distributed on the outer side wall of the central shaft of the inner rod, and the stirring wings on the outer rod and the stirring wings on the inner rod are arranged in an inner-outer layered manner and do not interfere with each other when rotating; the stirring wings positioned on the same layer rotate in the same direction along with the outer rod or in the same direction along with the inner rod, at least one fixed connection point is arranged between the stirring wings and the rod piece rotating in the same direction, and when the stirring wings are simultaneously connected with the rod piece rotating in the opposite direction, the stirring wings are rotationally connected with the rod piece. Compared with the prior art, the stirring wing design rotating along with the inner rod and the outer rod is adopted in the drilling tool structure, so that the problems of limited peripheral stirring capacity, poor stirring effect and the like of the stirring pile are solved, the shearing stirring with fewer stirring times than that of a conventional stirring construction method can be realized, the stirring effect can be achieved, the strength difference of the pile body of the stirring pile is greatly reduced, the overall strength is greatly improved, and the construction diameter of the stirring pile can reach 1500-3000 mm or even more by utilizing the structure. And the multi-channel flow distribution can be realized under the condition that the amount of the curing agent slurry required by the unit depth is ensured by a plurality of inner rod slurry distribution channels, and then the curing agent slurry is uniformly spread and distributed in each circumference of the pile body section through the slurry spraying seam, and the multi-circumference superposition effect is that the whole pile foundation section is covered, so that the curing agent uniform spreading of the whole section of the large-diameter pile is realized.

Preferably, the device further comprises a slurry digging drill bit and a plurality of digging wing plates, wherein the slurry digging drill bit is connected to the bottom of the inner rod, a drill bit slurry spraying channel communicated with the slurry passage of the inner rod is arranged in the slurry digging drill bit, and the plurality of digging wing plates are arranged on the peripheral wall of the slurry digging drill bit at intervals in the circumferential direction. The digging effect can be further improved through the slurry digging drill bit, and the slurry spraying effect is further improved.

Preferably, the direction of the plate surface of the digging wing plate forms an included angle theta with the cross section direction of the slurry digging drill bit, and the range of theta is 0-45 degrees. Through the structure, better shearing disturbance effect can be generated on soil in front of the plate in the rotating direction, and meanwhile, the increased resistance to the drill bit is reduced.

Preferably, the device further comprises a guniting pipe, wherein the guniting pipe is arranged at the bottom of the digging wing plate and is communicated with the inner rod slurry channel; and a guniting seam is arranged on the outer wall of the guniting pipe. Through the structure, stable spraying can be further carried out during stirring, and stirring uniformity is improved.

Preferably, the range covered by the guniting and spreading of all the guniting joints rotating around the central axis of the guniting and cutting drill bit is equal to the range of the circular ring obtained by subtracting the section of the inner rod from the section of the pile of the stirring pile. The structure can realize uniformity and comprehensiveness of guniting.

Preferably, the slurry spraying seam is arranged in a shadow area of a slurry spraying rotary earth facing surface at the bottom of the slurry spraying digging drill bit. The structure can effectively prevent soil from entering the guniting channel and ensure smooth guniting.

Preferably, the axial end face of the outer end of the guniting pipe is detachably connected with a rod-free slurry stop screw plug or a rod-bearing slurry stop screw plug. Through the structure, the difficulty of cleaning the blocked pipe is greatly reduced.

Preferably, when the stirring wings are in double-layer distribution, the following two installation modes are included; first mode: the stirring wings of the inner layer are arranged on the inner rod and are driven to rotate and stir by the inner rod; the stirring wings on the outer layer are arranged on the outer rod and are driven to rotate and stir by the outer rod; second mode: the stirring wings of the inner layer are arranged on the outer rod and are driven to rotate and stir by the outer rod; the stirring wings of the outer layer are arranged on the inner rod and are driven to rotate and stir by the inner rod. Different drilling patterns in different forms are realized through different numbers of stirring wings, and different requirements and diversity are realized.

Preferably, when the stirring wings are distributed in three layers, the following five installation modes are included; first mode: the stirring wings of the inner layer drive the rotation stirring through the inner rod; the stirring wings of the middle layer are driven by an outer rod to rotate and stir; the stirring wings on the outer layer drive the rotation stirring through the inner rod; second mode: the stirring wings of the inner layer drive the rotation stirring through the outer rod; the stirring wings of the middle layer are driven to rotate and stir through the inner rod; the stirring wings at the outer layer drive the rotation stirring through the outer rod; third mode: the stirring wings of the inner layer drive the rotation stirring through the outer rod; the stirring wings of the middle layer are driven to rotate and stir through the inner rod; the stirring wings on the outer layer drive the rotation stirring through the inner rod; fourth mode: the stirring wings of the inner layer drive the rotation stirring through the inner rod; the stirring wings of the middle layer are driven to rotate and stir through the inner rod; the stirring wings at the outer layer drive the rotation stirring through the outer rod; fifth mode: the stirring wings of the inner layer are simultaneously arranged on the inner rod and the outer rod, and respectively drive the rotation stirring through the inner rod and the outer rod; the stirring wings of the middle layer are driven to rotate and stir through the inner rod; the stirring wings at the outer layer drive the rotation stirring through the outer rod. Different drilling patterns in different forms are realized through different numbers of stirring wings, and different requirements and diversity are realized.

Preferably, when the stirring wings are distributed in four layers, the following two installation modes are included; first mode: the stirring wings of the inner layer drive the rotation stirring through the inner rod; the stirring wings of the middle inner layer drive the rotation stirring through the outer rod; the stirring wings of the middle outer layer drive the rotation stirring through the inner rod; the stirring wings at the outer layer drive the rotation stirring through the outer rod; second mode: the stirring wings of the inner layer drive the rotation stirring through the outer rod; the stirring wings of the middle inner layer drive the rotation stirring through the inner rod; the stirring wings of the middle outer layer drive the rotation stirring through the outer rod; the stirring wings on the outer layer drive the rotation stirring through the inner rod. Different drilling patterns in different forms are realized through different numbers of stirring wings, and different requirements and diversity are realized.

In summary, the utility model has the advantages that by adopting the stirring structure of the drilling tool, the problems of limited stirring area, poor mutual shearing effect of the stirring wings and the like caused by consistent track of the stirring wings are solved, larger-range soil disturbance can be realized, the stirring time is consistent compared with that of the conventional stirring construction method, the effect of more sufficient and uniform stirring can be realized, further, the strength difference of the pile body of the stirring pile is greatly reduced, the overall strength is greatly improved, and in addition, the problem that soil is easy to remain in a neutral area between the inner stirring wing and the outer stirring wing when the viscous soil wraps the drill bit to perform co-rotation and lift the drill can be well avoided by adopting the drilling tool.

Drawings

Fig. 1 is a schematic diagram of the whole structure of the drilling tool provided with the double-layer stirring wings.

Fig. 2 is a schematic cross-sectional view of a drilling tool with double-layer stirring wings according to the present utility model.

FIG. 3 is a schematic view of a portion of a parametric bit of the present utility model having dual channels disposed therein.

Fig. 4 is a schematic view of the drill bit section and bottom spray coverage of the dual channel drill of the present utility model.

Fig. 5 is a schematic view of the bottom gunite of the drill bit portion of the dual channel drilling tool of the present utility model.

FIG. 6 is a sectional view of the position of a gunite pipe and a gunite slit according to the present utility model.

Fig. 7 is a schematic cross-sectional view of a drill bit section of the present utility model, a slurry channel inside a slurry pipe, and a plug screw.

FIG. 8 is a schematic view of a slit structure and a plug of a drilling tool of the present utility model, wherein a is a schematic view of the slit of the drilling tool; b is a schematic diagram of the outside of the drilling tool guniting pipe slit; and c is a schematic diagram of the middle of the slit of the drilling tool guniting pipe.

Fig. 9 is a schematic diagram of the whole structure of the drilling tool provided with three layers of stirring wings.

Fig. 10 is a schematic cross-sectional view of a drilling tool with three layers of stirring wings according to the present utility model.

FIG. 11 is a schematic view of a three-channel parametric bit section of the present utility model.

Fig. 12 is a schematic view of the bottom of the drill bit portion of the three-channel drill of the present utility model and the coverage of the slurry jet.

FIG. 13 is an explanatory view of the arrangement of stirring wings in the present utility model, wherein a-e and p are double-layer stirring structures; f-j and m are three-layer stirring structures; k and n are four layers of stirring structures.

Wherein: 1. an outer rod; 101. an outer rod connector; 2. an inner rod; 201. an inner rod connector; 3. stirring wings; 3-1, a first layer of stirring wings; 3-2, a second layer of stirring wings; 3-3, a third layer of stirring wings; 3-4, a fourth layer of stirring wings; 4. an inner rod slurry passage; 5. a slurry-spraying digging drill bit; 501. a drill bit connector; 502. a drill bit center rod; 51. a drill bit guniting passage; 6. digging and cutting wing plates; 61. a guniting pipe; 61-1, a first guniting pipe; 61-2, a second guniting pipe; 61-3, a third guniting pipe; 610. a guniting pipe passage; 611. a rodless slurry stop screw plug; 612. a grouting stop screw plug with a rod; 6122. A plug screw thread; 6123. an inner hexagonal hole; 62. a guniting seam; 621. a guniting pipe thread; 62-1, a first guniting joint; 62-2, a second guniting joint; 62-3, a third guniting joint; 63. A first cutting tooth; 64. a helical wing plate; 65. a second cutting tooth; 7. a shadow area; 100. an outer drill rod; 200. an inner drill rod; 300. an inner drill rod passage.

Detailed Description

In order that the above objects, features and advantages of the utility model will be readily understood, a more particular description of the utility model will be rendered by reference to specific embodiments thereof which are illustrated in the appended drawings.

As shown in fig. 1 to 13, a drilling tool for construction of a large-diameter multi-layer shearing stirring pile comprises an outer rod 1, an inner rod 2, at least two stirring wings 3 and a plurality of digging wing plates 6; the outer rod 1 is connected with the outer drill rod 100 through an outer rod connector 101; the inner rod 2 is connected with the inner drill rod 200 through an inner rod connector 201, and at least one inner drill rod channel 300 is arranged in the inner drill rod 200; the inner rod 2 is provided with inner rod slurry running channels 4 which are corresponding to the inner drill rod channels 300 in number; the outer rod 1 is rotatably connected to the inner rod 2; at least one stirring wing 3 is radially distributed on the outer side wall of the central shaft of the outer rod 1; at least one stirring wing 3 is radially distributed on the outer side wall of the central shaft of the inner rod 2, and the stirring wings 3 on the outer rod 1 and the stirring wings 3 on the inner rod 2 are arranged in an inner-outer layered manner and do not interfere with each other when rotating; the stirring wings 3 on the same layer rotate in the same direction along with the outer rod 1 or rotate in the same direction along with the inner rod 2, at least one fixed connection point is arranged between the stirring wings 3 and the rod piece rotating in the same direction, and when the stirring wings 3 are simultaneously connected with the rod piece rotating in the opposite direction, the stirring wings 3 are rotationally connected with the rod piece. Compared with the prior art, the stirring wing 3 design rotating along with the inner rod and the outer rod is adopted in the drilling tool structure, so that the problems of limited peripheral stirring capacity, poor stirring effect and the like of the stirring pile are solved, the shearing stirring with fewer stirring times than that of a conventional stirring construction method can be realized, the stirring effect can be achieved, the pile body strength difference of the stirring pile is greatly reduced, the overall strength is greatly improved, and the construction diameter of the stirring pile can reach 1500-3000 mm or even more by utilizing the structure. And the multi-channel flow distribution can be realized under the condition that the curing agent slurry amount required by the unit depth is ensured by a plurality of inner rod slurry distribution channels, and then the curing agent slurry is uniformly spread and distributed in each circumference of the pile body section by the slurry spraying slits 62, and the multi-circumference superposition effect is that the whole pile foundation section is covered, so that the curing agent uniform spreading of the whole section of the large-diameter pile is realized.

Based on the operation mode of the stirring vane 3, various configurations can be performed: when the stirring wings 3 are in a double layer distribution as shown in fig. 13 (a) - (e) and (p); two mounting modes are formed; a first mode is for example fig. 13 (a): the stirring wings 3 of the inner layer are arranged on the inner rod 2 and are driven to rotate and stir by the inner rod 2; the stirring wings 3 on the outer layer are arranged on the outer rod 1 and are driven to rotate and stir by the outer rod 1; a second mode is, for example, fig. 13 (b) and (p): the stirring wings 3 of the inner layer are arranged on the outer rod 1 and are driven to rotate and stir by the outer rod 1; the stirring wings 3 of the outer layer are arranged on the inner rod 2 and are driven to rotate and stir by the inner rod 2. The stirring wings may be in the form of stirring blades or stirring frames. Different forms of drilling patterns are realized through different forms of stirring wings, and different requirements and diversity are realized.

When the stirring vane 3 adopts three layers of distribution, the following five modes are included, wherein the first mode is as follows: the stirring wings 3 of the inner layer drive the rotation stirring through the inner rod 2; the stirring wings 3 in the middle layer are driven to rotate and stir through the outer rod 1; the stirring wings 3 on the outer layer drive the rotation stirring through the inner rod 2; a second mode is, for example, fig. 13 (h): the stirring wings 3 of the inner layer drive the rotation stirring through the outer rod 1; the stirring wings 3 in the middle layer drive the rotation stirring through the inner rod 2; the stirring wings 3 of the outer layer are driven to rotate and stir by the outer rod 1. Third mode: the stirring wings 3 of the inner layer drive the rotation stirring through the outer rod 1; the stirring wings 3 in the middle layer drive the rotation stirring through the inner rod 2; the stirring wings 3 on the outer layer drive the rotation stirring through the inner rod 2; fourth mode such as fig. 13 (i): the stirring wings 3 of the inner layer drive the rotation stirring through the inner rod 2; the stirring wings 3 in the middle layer drive the rotation stirring through the inner rod 2; the stirring wings 3 of the outer layer are driven to rotate and stir by the outer rod 1. A fifth mode is shown in fig. 13 (g), (j) and (m), in which the stirring wings 3 of the inner layer are simultaneously provided on the inner rod 2 and the outer rod 1, respectively, and the rotation stirring is driven by the inner rod 2 and the outer rod 1, respectively; the stirring wings 3 in the middle layer drive the rotation stirring through the inner rod 2; the stirring wings 3 of the outer layer are driven to rotate and stir by the outer rod 1. Different drilling patterns in different forms are realized through different numbers of stirring wings, and different requirements and diversity are realized.

When the stirring wings 3 are distributed in four layers, the following two installation modes are included; a first mode is, for example, fig. 13 (k): the stirring wings 3 of the inner layer drive the rotation stirring through the inner rod 2; the stirring wings 3 in the middle inner layer drive the rotation stirring through the outer rod 1; the stirring wings 3 on the middle outer layer drive the rotation stirring through the inner rod 2; the stirring wings 3 on the outer layer drive the rotation stirring through the outer rod 1; second mode: the stirring wings 3 of the inner layer drive the rotation stirring through the outer rod 1; the stirring wings 3 of the middle inner layer drive the rotation stirring through the inner rod 2; the stirring wings 3 of the middle outer layer drive the rotation stirring through the outer rod 1; the stirring wings 3 on the outer layer are driven to rotate and stir by the inner rod 2. There may also be a different driving mode, for example, the stirring vane 3 is formed from an inner rod 2, an outer rod 1, an inner rod 2 or an inner rod 2, an outer rod 1, an inner rod 2 or an inner rod 2 from inside to outside an outer rod 1, an outer rod 1 or an inner rod 2, an outer rod 2, an inner rod 2 or an inner rod 2, an outer rod 1 drive, etc.

As shown in fig. 13 (d), the first layer stirring vane 3-1 has one fixed connection point with the outer rod 1 and more than one rotating connection point with the inner rod 2; as shown in fig. 13 (h), the third layer stirring vane 3-3 has two fixed connection points with the outer rod 1; in addition, comparing the first layer of stirring wings 3-1 of the drill structure of fig. 13 (a) and 13 (b), and the third layer of stirring wings 3-3 of the drill structure of fig. 13 (h) and 13 (i), it can be seen that the same layer of stirring wings 3 can be configured to rotate with the outer rod or rotate with the inner rod; further, comparing the third layer stirring wings 3-3 and the fourth layer stirring wings 3-4 of the drilling tool in fig. 13 (k) with those in fig. 13 (m), it can be seen that the stirring wings 3 can be arranged in a layered manner, and can be arranged in a nested layered manner or in a parallel layered manner. As shown in fig. 13 (n), the stirring wings 3 may be provided in a staggered arrangement with the inner and outer bars; compared with the prior art, the opposite rotating movement of the multi-layer stirring wings forms mutual shearing to soil layers, enhances the stirring disturbance effect and provides stirring conditions for more uniformly distributing the curing agent in the soil. In addition, the inner rod 2 or the outer rod 1 which are fixedly connected with more stirring wings 3 receives larger torque, and based on the larger torque, the rotation direction of the stirring wings 3 can be flexibly distributed and adjusted according to the torque received by the inner rod 2 and the outer rod 1 and the power of the power driving device.

As shown in fig. 13, the tracks formed by rotating the different stirring wings 3 in 360 ° of the same layer may be coincident, or partially coincident, or not coincident at all. As shown in the second layer stirring wings 3-2 shown in fig. 13 (a) and 13 (b), and the third layer stirring wings 3-3 shown in fig. 13 (g), the rotation tracks are completely misaligned due to different setting positions and heights of the stirring wings 3; as shown in fig. 13 (f), the second-layer stirring wings 3-2 partially overlap in rotation locus due to the difference in shape; as shown in fig. 13 (g), the second layer stirring wings 3-2 have branching structures at different positions of their bodies so that the rotation tracks partially overlap; as shown in fig. 13 (i), the first stirring vanes 3-1 are completely misaligned in the rotation locus due to their completely different shapes. Compared with the prior art, through adopting this kind of drilling tool stirring structure, the stirring area that has solved stirring wing 3 track uniformity and caused is limited, stirring wing 3 mutual shearing effect subalternation problem, can realize the soil body disturbance of a wide range, it is unanimous to realize than conventional stirring worker method stirring time, but can reach stirring more abundant more even effect, and then realize stirring stake pile body intensity difference and reduce by a wide margin and bulk strength improves by a wide margin, in addition, this drilling tool form can be fine avoid the cohesive soil parcel drill bit to take place to turn altogether and carry the problem that the soil body is easy to remain in the neutral region between the inside and outside stirring wing 3 when boring.

As shown in fig. 1 and 2, at least one inner rod slurry channel 4 is provided in the inner rod 2, and as shown in fig. 2, two inner rod slurry channels 4 are provided in this embodiment, and further, a slurry-spraying and cutting drill bit 5, a plurality of slurry-spraying and cutting wings 6 and a slurry-spraying pipe 61 are included, wherein the slurry-spraying and cutting drill bit 5 includes a drill bit connector 501 and a drill bit center rod 502; the drill bit center rod 502 is fixedly connected with the drill bit connector 501, the slurry-spraying digging drill bit 5 is connected to the bottom of the inner rod 2, and a drill bit slurry-spraying channel 51 communicated with the inner rod slurry-moving channel 4 is arranged in the slurry-spraying digging drill bit 5; the digging wing plate 6 is arranged at the bottom of the inner rod 2, a plurality of digging wing plates 6 are arranged on the peripheral wall of the slurry digging drill bit 5 at intervals in the circumferential direction, the slurry spraying pipe 61 is arranged at the bottom of the digging wing plate 6, and the slurry spraying pipe 61 is communicated with the drill bit slurry spraying channel 51. The slurry spraying pipe 61 is parallel to the surface of the digging wing plate 6, a slurry spraying seam 62 is arranged on the outer wall of the slurry spraying pipe 61, and slurry is sprayed out of the slurry spraying seam 62 through mutually communicated channels. The extent of coverage of the gunite spread by all the gunite slits 62 rotating around the central axis of the central rod 502 of the drill bit is the same as the extent of the circular ring obtained by subtracting the cross section of the central rod 502 of the drill bit from the pile cross section of the stirring pile.

The design of the drill bit part and the internal channel of the drilling tool can realize multi-channel flow distribution under the condition of ensuring the required curing agent slurry amount per unit depth, and the multi-slurry conveying pumps work independently at the same time, so that the curing agent slurry is uniformly spread in each circumference of the pile body section through the slurry spraying seam 62, the multi-circumference superposition effect is that the whole pile foundation section is covered, and the curing agent uniform spreading of the whole section of the large-diameter pile is achieved. The curing agent slurry is not enriched any more, the problem of slurry returning is solved, the mixing amount of the curing agent in the soil body within each unit depth range is ensured to be consistent, and the strength difference of the final cured soil at each point is further realized to be as small as possible. By utilizing the structure, the construction diameter of the stirring pile can reach 1500 mm-3000 mm, and even larger.

As shown in fig. 3 to 6, the slurry spraying slit 62 is formed by surrounding the bottom surface of the digging wing plate 6 and the gap provided on the slurry spraying pipe 61, or the slurry spraying slit 62 is formed by perforating the side wall of the slurry spraying pipe channel 610. Thus, different guniting through slits are arranged according to the guniting amount, and meanwhile, due to the slit-shaped structural design, when the guniting slits 62 are locally blocked, the slurry in the unblocked part is flushed to the full slits, so that the blocking problem of the guniting opening is effectively avoided. As shown in fig. 4 and 8, the width of the gunite gap 62 is determined by the area of the ring to be covered.

As shown in fig. 6, a slurry injection slit 62 is provided in the shadow area 7 of the slurry injection rotary earth-facing surface of the slurry injection cutting bit 5. Can effectively prevent soil from entering the guniting channel and ensure smooth guniting. As shown in fig. 6, the angle θ1 between the plate surface direction of the digging wing plate 6 and the cross-sectional direction of the drill bit central rod 502 is in the range of 0 ° to 45 °. The device can generate better shearing disturbance action on soil in front of the plate in the rotating direction, and simultaneously reduces the increased resistance to the drill bit.

As shown in fig. 7 and 8, the axial end face of the outer end of the gunite channel 610 inside the gunite 61 is provided with a detachable rodless or rod-mounted stop screw 611, 612 depending on the position of the slit. The setting of stopping plug screw has greatly reduced the degree of difficulty of clearance stifled pipe when the condition that the spraying passageway produced the jam because of too big particulate matter can't discharge. As shown in fig. 7, the rodless stop screw 611 or the rod-mounted stop screw 612 is mounted at the end of the digging wing plate 6 and is provided with a screw thread 6122 matching with the guniting pipe thread 621, and the screw end is provided with an internal hexagonal hole 6123, which further increases the convenience of removing the stop screw. Wherein the rod stop screw 612 is provided to prevent the curing agent slurry from building up and curing in the unset areas of the gunite tube 61 to form a hardened plug.

The application method of the drilling tool for the construction of the large-diameter multilayer mutual shearing stirring pile comprises the following process steps:

Before the stirring pile machine starts to be constructed, checking the slurry conveying smoothness of the whole drilling tool, starting to supply solidified material slurry to the background of the drilling machine through a plurality of slurry conveying pumps, wherein each slurry conveying pump corresponds to one inner rod slurry conveying channel 4, the solidified material slurry flows through the inner rod slurry conveying channel 4 and the drill bit slurry spraying channel 51 through the inner rod slurry conveying channel 300 to enter the slurry spraying pipe channel 610, and finally is sprayed out through the slurry spraying seam 62, and the condition that the slurry is normally supplied and the channels are not blocked is indicated; meanwhile, checking whether the opposite rotation of the inner rod and the outer rod driven by the power device is normal, and if so, performing the next step.

The drilling tool starts to drill down and rotate, the soil in front of the plate is subjected to upward and forward component force by the action of the digging wing plate 6, a cavity with a certain space is formed behind the plate, and simultaneously, the slurry spraying seam 62 continuously sprays slurry of the curing agent into the cut soil uniformly. When the stirring wings 3 connected with the inner rod and the outer rod reach the position of the soil body mixed by spraying, the soil body containing slurry is further sheared and stirred to be more uniform, and after the stirring drilling tool drills to the elevation of the pile bottom, the pile body is uniformly mixed with curing agent slurry, and meanwhile, one-spraying one-stirring construction is completed;

And finally, closing the background slurry conveying, starting the reverse lifting of the drilling tool, stirring the pile body cement soil again, and improving the uniformity again, and when the stirring drilling tool is lifted to leave the ground, completing one-spraying two-stirring construction so far, and finishing the construction; if necessary, repeating the above steps for one time to finish the two-spray four-stirring construction; after the construction is finished, clear water is pumped in the background, residual slurry or residues in the drill rod, the drill bit central rod 502 and the guniting channel are flushed out, and if the residual slurry or the residues cannot be flushed out, the guniting channel can be cleaned to be unobstructed again by means of a tool through disassembling the slurry stop plug.

This will be further illustrated by the following two examples:

Example 1

This example is to construct a large diameter mixing pile with a pile diameter d=1500mm. The diameter of the drill bit central tube is d=173 mm, and two grouting pumps are adopted for simultaneous grouting in the background.

Specifically, as shown in fig. 1, the double-layer drilling tool adopted in this embodiment is powered by the pin connection between the inner drill rod 200 and the inner rod connector 201 and the pin connection between the outer drill rod 100 and the outer rod connector 101, the whole drilling tool adopts a double-layer stirring wing 3 structure, the stirring wings 3 rotating along with the outer rod 1 are in an "E" shape, three stirring wings are radially distributed on the outer surface of the outer rod 1 in total, and the two included angles are 120 °. The stirring wings 3 rotating along with the inner rod 2 are in a straight plate shape, are radially distributed on the outer surface of the inner rod 2 and are arranged in staggered layers, and the horizontal included angle of the stirring wings of the adjacent layers is 120 degrees. When the inner rod and the outer rod rotate oppositely, the stirring wings 3 which are closer to the inner rod and the outer rod shear and disturb soil, and the staggered-layer stirring wings 3 on the inner rod 2 perform layered disturbance on a neutral area which cannot be contacted by the stirring wings 3 on the outer rod 1, so that the soil in the area can be fully stirred.

In addition, as shown in fig. 2, in this embodiment, the inner drill pipe channel 300 is connected to the inner rod slurry channel 4, and is sequentially connected to the bit slurry spraying channel 51 and the slurry spraying pipe channel 610 in the distributed slurry drilling bit 5, so as to supply and circulate the curing agent slurry. As shown in fig. 3, the distributed slurry-spraying digging drill bit 5 is provided with two digging wing plates 6 and spiral wing plates 64 which are arranged at 180 degrees, the digging wing plates 6 are provided with a plurality of first digging teeth 63 which are arranged at intervals, and the end parts of the spiral wing plates 64 are provided with a plurality of second digging teeth 65 which are arranged at intervals, so that the drilling tool can effectively dig into the deep part of a soil layer, and particularly, the drilling tool has better digging effect on a hard soil layer. As shown in fig. 5, two slurry pipe groups are disposed in parallel below the cutting blade 6, and form a slurry jet slit 62, the slit width and slit position of which are shown in fig. 4, 8 (a) and 8 (b), the first slurry jet slit 62-1 of the first slurry pipe 61-1 is opened on the side close to the bit center shaft 502, the slit width is L1, the second slurry jet slit 62-2 of the second slurry pipe 61-2 is opened on the side far from the bit center shaft 502, and the slit width is L2, and l1+l2=d-D. When the distributed slurry spraying and cutting drill bit 5 rotates to spray slurry continuously, the whole section of the pile foundation can be covered completely, so that the purpose of uniform slurry distribution is achieved.

Before construction is started, the activity of the stirring wings 3 and the digging wings 3 of the drilling tool and the smoothness of each channel are checked, when a certain guniting channel is abnormal, the screw plug is screwed out by using an inner hexagonal wrench, and the guniting channel and the guniting seam 62 are dredged to be smooth by using other tools, and then the screw plug is recovered. And (5) spraying slurry to drill down after the test spraying is performed again without abnormality, and stopping spraying and lifting. To complete the construction of the pile foundation.

Example two

This example is to construct a large diameter mixing pile with a pile diameter d=3000 mm. The diameter of the drill center tube is d=219 mm, and three grouting pumps are adopted for simultaneous grouting in the background.

Specifically, as shown in fig. 1, the double-layer drilling tool adopted in this embodiment is pinned with the inner rod connector 201 through the inner drill rod 200 and is in flanged connection with the outer rod connector 101 through the outer drill rod 100, and the structure of the three-layer stirring wings 3 is shown in fig. 9, wherein the stirring wings 3 of the outermost layer and the innermost layer rotate along with the outer rod 1, three stirring wings are distributed radially on the outer surface of the outer rod 1 in total, and an included angle between two adjacent stirring wings is 120 °. The middle layer stirring wings 3 rotating along with the inner rod 2 are distributed on the outer surface of the inner rod 2 at intervals of 180 degrees. When the inner rod and the outer rod rotate oppositely, the stirring wings 3 of the inner rod and the outer rod which are closer in distance perform shearing disturbance on soil in multiple directions, and due to arrangement of the three layers of stirring wings, rotation tracks of the stirring wings are not completely overlapped, soil in different areas can be stirred respectively and soil in the same area can be stirred repeatedly, the stirring effect and uniformity are greatly improved, insufficient stirring caused by overlarge stirring pile diameter is avoided, and the effect is poor.

In addition, as shown in fig. 9, the slurry running mode adopted in this embodiment is similar to that of the embodiment, except that as shown in fig. 11, the distributed slurry-spraying drilling bit 5 is provided with three digging wing plates 6 and spiral wing plates 64 which are arranged at 120 degrees, the digging wing plates 6 are provided with a plurality of first digging teeth 63 which are arranged at intervals, and the end parts of the spiral wing plates 64 are provided with a plurality of second digging teeth 65 which are arranged at intervals, so that the drilling tool can effectively dig into the deep part of the soil. The three slurry pipe groups are arranged in parallel below the cutting wing plate 6, and form slurry jet slits 62, the slit width and slit positions of which are shown in fig. 12, 8 (a), 8 (b) and 8 (c), the first slurry jet slit 62-1 of the first slurry pipe 61-1 is opened on the side close to the center shank 502 of the drill bit, the slit width is L1, the second slurry jet slit 62-2 of the second slurry pipe 61-2 is opened on the side far from the center shank 502 of the drill bit, the slit width is L2, the third slurry jet slit 62-3 of the third slurry pipe 61-3 is opened at a relatively middle position, and the slit width is L3, l1+l2+l3=d-D. The design can effectively avoid the condition of insufficient grouting pump flow supply caused by overlarge diameter of the stirring pile and huge curing dosage required to be doped into the pile body in unit length, and the ultra-high-power grouting pump is not required to be used, three conventional pumps are used for shunting, and the pile body coverage areas respectively responsible for the shunting are controlled to spread slurry, so that uniform spreading of the whole pile foundation section is finally realized.

In summary, the utility model has the advantages that by adopting the stirring structure of the drilling tool, the problems of limited stirring area, poor mutual shearing effect of the stirring wings 3 and the like caused by consistent track of the stirring wings 3 are solved, larger-range soil disturbance can be realized, the stirring time is consistent compared with that of the conventional stirring construction method, the effect of more sufficient and uniform stirring can be realized, further, the strength difference of the pile body of the stirring pile is greatly reduced, the overall strength is greatly improved, and in addition, the drilling tool can well avoid the problems that the viscous soil wraps the drill bit to generate co-rotation and the soil is easy to remain in a neutral area between the inner stirring wing and the outer stirring wing 3 during lifting.

Although the present disclosure is described above, the scope of protection of the present disclosure is not limited thereto. Various changes and modifications may be made by one skilled in the art without departing from the spirit and scope of the disclosure, and these changes and modifications will fall within the scope of the utility model.

Claims (7)

1. The drilling tool for the construction of the large-diameter multilayer mutual shearing stirring pile is characterized by comprising an outer rod (1), an inner rod (2) and at least two stirring wings (3); at least one inner rod pulp passage (4) is arranged in the inner rod (2); the outer rod (1) is rotatably connected to the inner rod (2); at least one stirring wing (3) is radially distributed on the outer side wall of the central shaft of the outer rod (1); at least one stirring wing (3) is radially distributed on the outer side wall of the central shaft of the inner rod (2), and the stirring wings (3) on the outer rod (1) and the stirring wings (3) on the inner rod (2) are arranged in an inner-outer layered manner and do not interfere with each other during rotation; the stirring wings (3) located on the same layer rotate in the same direction along with the outer rod (1) or rotate in the same direction along with the inner rod (2), at least one fixed connection point is arranged between the stirring wings (3) and the rod piece rotating in the same direction, and when the stirring wings (3) are simultaneously connected with the rod piece rotating in the opposite direction, the stirring wings (3) are rotationally connected with the rod piece.

2. The drilling tool for construction of the large-diameter multi-layer shearing stirring pile according to claim 1, further comprising a slurry-spraying cutting drill bit (5) and a plurality of slurry-spraying cutting wing plates (6), wherein the slurry-spraying cutting drill bit (5) is connected to the bottom of the inner rod (2), a drill-bit slurry-spraying passage (51) communicated with the inner rod slurry-moving passage (4) is arranged in the slurry-spraying cutting drill bit (5), and the plurality of slurry-spraying wing plates (6) are arranged on the peripheral wall of the slurry-spraying cutting drill bit (5) at intervals in the circumferential direction.

3. Drilling tool for construction of large diameter multi-layer inter-shearing stirring pile according to claim 2, characterized in that the plate direction of the digging wing plate (6) forms an angle θ with the cross-sectional direction of the slurry digging drill bit (5), θ being in the range of 0-45 °.

4. The drilling tool for construction of large-diameter multi-layer mutual shearing stirring pile according to claim 2, further comprising a slurry spraying pipe (61), wherein the slurry spraying pipe (61) is arranged at the bottom of the digging wing plate (6), and the slurry spraying pipe (61) is communicated with the inner rod slurry channel (4); the outer wall of the guniting pipe (61) is provided with a guniting seam (62).

5. Drilling tool for construction of large diameter multi-layer inter-shearing mixing pile according to claim 4, characterized in that the range of the spraying slurry spreading coverage of all the spraying slurry slits (62) rotating around the central axis of the spraying slurry digging drill bit (5) is equal to the range of the circular ring obtained by subtracting the section of the inner rod (2) from the pile section of the mixing pile.

6. Drilling tool for construction of large diameter multi-layer inter-shear mixing piles according to claim 4, characterized in that the guniting slits (62) are arranged in the shadow area (7) of the guniting rotary earth-facing surface at the bottom of the guniting cutting drill bit (5).

7. The drilling tool for construction of large-diameter multi-layer shearing stirring pile according to claim 4, characterized in that the axial end face of the outer end of the guniting pipe (61) is detachably connected with a rod-free grout stop screw (611) or a rod-bearing grout stop screw (612).