Mixing pile for soft soil foundation anti-settlement reinforcement

Abstract

The utility model discloses a kind of for soft soil foundation anti-settling reinforcement's mixing pile, top is enlarged head, the bottom of enlarged head is downwardly extending mixing pile, it is circular table transition section between enlarged head and mixing pile, constitute a mixing pile with enlarged head and have circular table transition section;Mixing pile with enlarged head and have circular table transition section are multiple rows, each row has multiple roots;Adjacent row's enlarged head is staggered between each other;Adjacent enlarged head leaves gap between each other, or adjacent enlarged head is tangent between each other, or adjacent enlarged head is mutually occluded between each other;The gap size that adjacent enlarged head leaves between each other is 1mm-50mm;The circular table transition section is smooth circular table transition section or stepped circular table transition section.The mixing pile construction speed is fast, soft soil foundation reinforcement treatment cost is relatively low, compression resistance, shear resistance and bearing capacity are substantially improved, and soft soil foundation anti-settling reinforcement effect is remarkable.

Description

Technical Field

[0001] This utility model relates to the field of pile foundation construction technology, specifically a mixing pile for preventing settlement and reinforcing soft soil foundations. Background Technology

[0002] The existing cement-soil mixing pile is simply called a mixing pile. The construction method and pile driver for mixing piles are relatively mature. During construction, the winch drives the power head up and down, and the power head drives the drill rod to rotate. On one hand, cement slurry is sprayed out through the slurry pipe inside the drill rod and the nozzle on the mixing drill head. On the other hand, the mixing drill head drills down and stirs the cement-soil. After the cement slurry solidifies, it becomes a mixing pile.

[0003] In existing technologies, for the reinforcement of large-area soft soil foundations, such as soft soil subgrades of highways and high-grade roads, soft soil foundations of airport runways, and soft soil foundations of urban construction plazas, there are mixing piles with different structures, but each has its own shortcomings:

[0004] In the early stages, multiple mixing piles with a depth of 10-24 meters and a diameter of 500mm-1000mm were used to form an anti-settlement structure for soft soil foundations. However, the disadvantages were obvious. If the density was too low, the settlement between the gaps would be uneven, and the anti-settlement reinforcement effect would be unsatisfactory. If the density was too high, too many mixing piles would be needed, the cost would be too high, and there would be too much waste of materials.

[0005] Later, technicians adopted a mixing pile structure, with several mixing piles of conventional depth at the bottom, and then a hardened layer of cement-soil mixing piles several meters deep constructed on top of these mixing piles. However, to form the hardened layer of cement-soil mixing piles on top of the mixing piles, it is necessary to construct the cement-soil hardened layer composed of several mixing piles several meters deep by vertically alternating shallow and deep sections and horizontally alternating sections. The equipment is relatively complex, the amount of construction is relatively large, the construction time is relatively long, the construction speed is relatively slow, and the cost of soft soil foundation reinforcement is relatively high.

[0006] Some technicians also use the mixing drill bit of the pile driver to rotate forward to determine the diameter of the mixing pile, and reverse the rotation of the mixing drill bit to determine the diameter of the enlarged head. This results in the construction of mixing piles with T-shaped enlarged heads at the top. However, because the T-shaped enlarged head transitions to the mixing pile at a right angle, its compressive and shear strength is significantly insufficient. Furthermore, the horizontal arrangement of the enlarged heads is unreasonable, resulting in an unsatisfactory effect on the settlement prevention and reinforcement of soft soil foundations. Utility Model Content

[0007] One technical problem this invention aims to solve is to provide a mixing pile for soft soil foundation anti-settlement reinforcement that features fast construction speed, relatively low cost of soft soil foundation reinforcement, significantly improved compressive and shear strength, and remarkable anti-settlement reinforcement effect.

[0008] The technical solution of this utility model is to provide a mixing pile for the anti-settlement reinforcement of soft soil foundation. The top is an enlarged head, the bottom of the enlarged head is a mixing pile extending downward, and there is a frustum transition section between the enlarged head and the mixing pile, forming a mixing pile with an enlarged head and a frustum transition section. There are multiple rows of mixing piles with enlarged heads and frustum transition sections, and multiple piles in each row. There are gaps between adjacent enlarged heads, or adjacent enlarged heads are tangent to each other, or adjacent enlarged heads are interlocked.

[0009] With the above structure, the mixing pile of this utility model for settlement prevention and reinforcement of soft soil foundation has the following advantages:

[0010] Because the enlarged head is placed at the top of the mixing pile, the coaxial enlarged head and mixing pile can be constructed in one go, saving labor, time, and materials such as cement and electricity consumption. The construction efficiency is high, and the cost of soft soil foundation anti-settlement reinforcement treatment is relatively low.

[0011] Because the enlarged head and the mixing pile are connected by a frustum transition section, the compressive strength, shear strength and bearing capacity of the mixing pile with the enlarged head are greatly improved.

[0012] In particular, depending on the actual geological conditions and engineering needs, the enlarged heads of adjacent rows can be staggered, with gaps between adjacent enlarged heads, or adjacent enlarged heads can be tangent to each other, or adjacent enlarged heads can be interlocked, making the anti-settlement reinforcement effect of soft soil foundations significant.

[0013] Furthermore, the enlarged heads in adjacent rows are arranged in a staggered manner. This structure results in a rational horizontal arrangement of the enlarged heads, further improving the settlement prevention and reinforcement effect on soft soil foundations.

[0014] Furthermore, the staggered arrangement structure is as follows: the diameter line of a circle of each enlarged head in a row is perpendicular to the line connecting the centers of two adjacent enlarged heads in an adjacent row, and the diameter line of this circle bisects the line connecting the centers. With this structure, the staggered arrangement is highly rational, significantly improving the anti-settlement reinforcement effect on soft soil foundations and saving materials such as cement.

[0015] Furthermore, the gap between adjacent enlarged heads is 1mm-50mm. Using this structure, the gaps not only save on materials such as cement and electricity, but also ensure a significant anti-settlement reinforcement effect on soft soil foundations.

[0016] Furthermore, the frustum transition section can be a smooth frustum transition section or a stepped frustum transition section. With the above structure, both types of frustum transition sections can significantly improve the compressive strength, shear strength, and bearing capacity of the mixing pile with the enlarged head. Of course, the smooth frustum transition section is preferred. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of an embodiment of the present invention, which uses a mixing pile for settlement prevention and reinforcement of soft soil foundation, wherein adjacent enlarged heads are spaced apart.

[0018] Figure 2 This is a schematic diagram of an embodiment of the mixing pile for preventing settlement and reinforcing soft soil foundations, in which adjacent enlarged heads are tangent to each other.

[0019] Figure 3 This is a schematic diagram of an embodiment of the mixing pile for preventing settlement and reinforcing soft soil foundations, showing the interlocking of adjacent enlarged heads.

[0020] Figure 4 This is an enlarged schematic diagram of the structure of an embodiment of the frustum-shaped transition section of a single mixing pile with an enlarged head in this utility model.

[0021] Figure 5 This is a schematic diagram of the structure of a mixing pile with an enlarged head constructed by a pile driver (the height of the first drill rod is omitted; the wire rope and some bolts and nuts are omitted; the cement and soil inside the enlarged head, the truncated cone transition section, and the mixing pile are omitted).

[0022] Figure 6 This is a structural schematic diagram of the pile driver used for constructing this mixing pile (the first drill rod is drawn with its height omitted); Figure 6 The steel wire rope was omitted. Figure 6 , Figure 7 and Figure 8 (Some bolts and nuts omitted).

[0023] Figure 7 yes Figure 6 A magnified structural diagram of A in the diagram.

[0024] Figure 8 yes Figure 7 The diagram shows the structure of the inclined plate in the second stirring head, which uses an inclined stepped plate.

[0025] Figure 9 yes Figure 6 A magnified structural diagram of B in the diagram.

[0026] As shown in the figure:

[0027] 1. Pile driver; 11. Traveling mechanism; 12. Construction platform; 13. Tower; 14. Winch mechanism; 15. Control room;

[0028] 2. Two-way mixing device for mixing piles, 21. First power head, 22. First drill rod, 221. First inner drill rod, 222. First outer drill rod, 23. First mixing head, 231. First inner transverse mixing blade, 232. First mixing frame, 2321. First upper connecting sleeve, 2322. First lower connecting sleeve, 2323. First frame leaf, 23231. First upper horizontal plate, 23232. First vertical plate, 23233. First lower horizontal plate, 233. First outer transverse mixing blade;

[0029] 3. Expanded head bidirectional stirring device, 31. Second power head, 3100. First drill rod through hole, 32. Second drill rod, 321. Second inner drill rod, 322. Second outer drill rod, 33. Second stirring head, 331. Second inner transverse stirring blade, 332. Second stirring frame, 3321. Second upper connecting sleeve, 3322. Second lower connecting sleeve, 3323. Second frame, 33231. Second upper horizontal plate, 33232. Second vertical plate, 33233. Inclined plate, 332331. Inclined straight plate, 332332. Inclined step plate, 33234. Second lower horizontal plate, 333. Second outer transverse stirring blade;

[0030] 4. Drill bit; 41. Drill tip; 42. Drill bit body; 43. Drill bit agitator blades;

[0031] 51. Enlarged head; 52. Frustum transition section; 521. Smooth frustum transition section; 522. Stepped frustum transition section; 53. Mixing pile; 54. Diameter line; 55. Center connection line.

[0032] 61. Grout delivery pipe; 62. Connector; 63. Grout nozzle;

[0033] 7. Soil. Detailed Implementation

[0034] The specific embodiments of this utility model will be further described below with reference to the accompanying drawings. It should be noted that these descriptions of specific embodiments are intended to aid in understanding this utility model, but do not constitute a limitation thereof. Furthermore, the technical features involved in the various specific embodiments of this utility model described below can be combined with each other as long as they do not conflict with each other.

[0035] like Figure 1 , Figure 2 , Figure 3 and Figure 4 As shown.

[0036] This utility model discloses an embodiment of a mixing pile for preventing settlement and reinforcing soft soil foundations. The top is an enlarged head 51, the bottom of which is a downwardly extending mixing pile 53. A frustum-shaped transition section 52 connects the enlarged head 51 and the mixing pile 53, forming a mixing pile 53 with an enlarged head 51 and a frustum-shaped transition section 52. Multiple rows of these mixing piles 53 are arranged, with multiple piles in each row. Adjacent enlarged heads 51 are spaced apart, tangent to each other, or interlocked.

[0037] The enlarged heads 51 in adjacent rows can be arranged in an alternating manner. The specific structure of the alternating arrangement can be as follows: the diameter line 54 of a circle of each enlarged head 51 in a row is perpendicular to the line 55 connecting the centers of two adjacent enlarged heads 51 in an adjacent row, and the diameter line 54 bisects the line 55 connecting the centers.

[0038] The size 'a' of the gap between adjacent enlarged heads 51 can be 1mm-50mm.

[0039] The frustum transition section 52 can be a smooth frustum transition section 521 or a stepped frustum transition section 522.

[0040] like Figure 1 , Figure 2 , Figure 3 , Figure 4 , Figure 5 , Figure 6 , Figure 7 , Figure 8 and Figure 9 As shown.

[0041] The following structure can be used for the construction of mixing piles for the anti-settlement reinforcement of soft soil foundations. The mixing pile 1 includes a walking mechanism 11, such as a walking mechanism, a construction platform 12, a tower 13 fixed on the construction platform 12 and an operating room 15, a grout delivery pipe and a grout spraying nozzle 6, and a power head driven by a winch mechanism 14 and vertically slidably coupled to a bidirectional mixing device on the tower 13.

[0042] There are two sets of bidirectional mixing devices: one set is the bidirectional mixing device 2 for mixing piles, and the other set is the bidirectional mixing device 3 for enlarged head.

[0043] The first power head 21 of the bidirectional mixing device 2 for mixing piles is located above the second power head 31 of the bidirectional mixing device 3 for enlarged heads. The first drill rod 22 of the bidirectional mixing device 2 passes through the first drill rod through hole 3100 on the second power head 31 of the bidirectional mixing device 3 for enlarged heads. There is a large gap between the first outer drill rod 222 of the first drill rod 22 and the hole wall of the first drill rod through hole 3100. The second mixing head 33 for mixing out the enlarged head 51 is below the second power head 31, and the first mixing head 23 for mixing out the mixing pile 53 is below the second mixing head 33.

[0044] The upper end of the first inner drill rod 221 is connected to the first power head 21, and the upper end of the first outer drill rod 222 is also connected to the first power head 21.

[0045] The specific structure of the first stirring head 23 can be as follows: the lower end of the first inner drill rod 221 is fixed with multiple, such as two, first inner transverse stirring blades 231; the lower end of the first outer drill rod 222 is fixed with a first stirring frame 232; the inner side of the first stirring frame 232, such as the inner side of the first frame 2323, is fixed with multiple, such as welded, first outer transverse stirring blades 233 that are staggered in height from the first inner transverse stirring blades 231 and stir each other in both directions.

[0046] The specific structure of the first mixing frame 232 can be as follows: the first mixing frame 232, consisting of three first frame panels 2323, forms the mixing pile 53 with a small diameter. The included angle between the width bisectors of two adjacent first frame panels 2323 is 120°. The inner end of the first upper horizontal plate 23231 of each first frame panel 2323 is fixed to a first upper connecting sleeve 2321. The first upper connecting sleeve 2321 is fixed by welding or by screwing to the bottom end of the first outer drill rod 222. The outer end of the first upper horizontal plate 23231 is fixed to the upper end of the first vertical plate 23232. The lower end of the first vertical plate 23232 is fixed to the outer end of the first lower horizontal plate 23233. The inner end of the first lower horizontal plate 23233 is fixed to a first lower connecting sleeve 2322. The first lower connecting sleeve 2322 is rotatably engaged with the bottom end of the first inner drill rod 221. Multiple first inner transverse stirring blades 231 are distributed around the circumference of the first inner drill rod 221, and the included angle between the width bisectors of two adjacent vertically arranged rows of first inner transverse stirring blades 231 can be 120° to each other. The components of the first stirring frame 232 can be fixed together by integral molding, welding, or multiple bolts.

[0047] The drill bit 4 is fixed to the bottom end of the first inner drill rod 221. The drill bit 4 may include a drill tip 41 at the bottom end, such as the drill tip 41 of a triangular plate, a drill bit body 42 at the top of the drill tip 41, and drill bit stirring blades 43 symmetrically arranged on both sides of the drill bit body 42. The grouting nozzle 6 may be provided on the drill bit body 42, and the grouting nozzle 6 is connected to the grouting pipe provided in the first inner drill rod 221.

[0048] The upper end of the second inner drill rod 321 of the second drill rod 32 is connected to the second power head 31, and the upper end of the second outer drill rod 322 is also connected to the second power head 31.

[0049] The specific structure of the second stirring head 33 can be as follows: multiple second inner transverse stirring blades 331 are fixed or welded to the lower end of the second inner drill rod 321. A second stirring frame 332 is fixed to the lower end of the second outer drill rod 322. Multiple second outer transverse stirring blades 333, which are staggered in height from the second inner transverse stirring blades 331 and stir each other in both directions, are fixed or welded to the inner side of the second stirring frame 332, such as the inner side of the second frame 3323.

[0050] The second stirring head 33 includes multiple second vertical plates 33232 that stir out a large diameter enlarged head 51 and multiple inclined plates 33233 that stir out a frustum transition section 52 from the outside upper to the inside lower, with each inclined plate 33233 fixed to the bottom end of each second vertical plate 33232.

[0051] The specific structure of the second stirring frame 332 can be as follows: the second stirring frame 332 consists of three second frame panels 3323 forming a large-diameter enlarged head 51 and a frustum transition section 52. The included angle between the width bisectors of two adjacent second frame panels 3323 is 120°. The inner end of the second upper horizontal plate 33231 of each second frame panel 3323 is fixed to a second upper connecting sleeve 3321. The second upper connecting sleeve 3321 is fixed by welding or by screwing to the bottom end of the second outer drill rod 322. The outer end of the second upper horizontal plate 33231 is fixed to the upper end of the second vertical plate 33232. The lower end of the second vertical plate 33232 is fixed to the upper end of the inclined plate 33233. The lower end of the inclined plate 33233 is fixed to the outer end of the second lower horizontal plate 33234. The inner end of the second lower horizontal plate 33234 is fixed to a second lower connecting sleeve 3322. The second lower connecting sleeve 3322 is rotatably engaged with the bottom end of the second inner drill rod 321. The second outer transverse stirring blade 333, which is fixed inside the three second frame pages 3323 of the second stirring frame 332, can be two blades. That is, the second transverse stirring blade 33 fixed on the second vertical plate 33232 can be horizontal, and the second transverse stirring blade 33 fixed on the inclined plate 33233 can be inclined with the outer bottom and the inner top.

[0052] The second upper horizontal plate 33231 is fixed to the second vertical plate 33232, the second vertical plate 33232 is fixed to the inclined plate 33233, and the inclined plate 33233 is fixed to the second lower horizontal plate 33234. This can be achieved by repeatedly bending a long strip plate, with all corners being arc-shaped transition surfaces. The angle between the expanded head 51 and the frustum transition section 52 is an arc angle, as is the angle between the frustum transition section 52 and the mixing pile 53. Of course, the plates can also be aligned and welded together, with the corners being right angles or obtuse angles.

[0053] The inclined plate 33233 can be a straight inclined plate 332331 with a smooth outer surface. Alternatively, it can be an inclined stepped plate 332332 with multiple steps. As described above, the second frame formed by the straight inclined plate 332331 with a smooth outer surface creates a smooth frustum transition section 521, and the second frame formed by multiple inclined stepped plates 332332 creates a stepped frustum transition section 522. A step can be understood as an inverted step or a toothed frustum transition section.

[0054] The first outer drill rod 222 and the second inner drill rod 321 slide together in the inner hole.

[0055] It is easy to understand that the upper end of the second inner drill rod 321 is on the second power head 31, and there is no obstruction between the inner hole of the upper end of the second inner drill rod 321 and the first drill rod through hole 3100 on the cover plate of the second power head 31. Therefore, as long as the first outer drill rod 222 passes through the first drill rod through hole 3100 and the inner hole of the upper end of the second inner drill rod 321, it will pass through the second power head 31.

[0056] The top end of the grout delivery pipe fixed inside the drill rod, such as the first inner drill rod 221, has a connector for connecting the grout inlet pipe. The grout inlet pipe is connected to the grout pump and grout pool located on the ground. The bottom end of the grout delivery pipe is connected to multiple grout nozzles 6 on the drill bit 4, such as multiple grout nozzles 6 located on the drill bit body 42 described below.

[0057] This utility model relates to a mixing pile for preventing settlement and reinforcing soft soil foundations. The following construction method and steps are described below:

[0058] 1) The walking mechanism 11 is operated to align the axis of the drill bit 4 of the combined bidirectional mixing device of the pile driver 1 with the construction position of the mixing pile 53 of the soil body 7. It is easy to understand that the mixing pile 53 refers to the mixing pile 53 of this utility model that is equipped with an enlarged head 51 and a frustum transition section 52.

[0059] 2) Operation of the bidirectional mixing device 2 for mixing piles: Power is turned on to make the first power head 21 rotate. At the same time, the winch mechanism 14 is controlled to drive the uppermost first power head 21 and drive the lowermost bidirectional mixing head 23 and drill bit 4 to drill down and mix through the first inner drill rod 221 and the first outer drill rod 222 of the first drill rod 22. Multiple grouting nozzles 6 on the drill bit 4 spray grout at the same time to construct the mixing pile 53.

[0060] Operating the bidirectional stirring device 3 of the enlarged head: Turn on the power to make the second power head 31 rotate, and at the same time control the winch mechanism 14 to drive the second power head 31 located below the first power head 21, and drive the second inner drill rod 321 and the second outer drill rod 322 of the second inner drill rod 32 to drive the bidirectional stirring second stirring head 33 located above the first stirring head 23 to stir downwards, and construct the enlarged head 51.

[0061] 3) Operation: The mixing pile bidirectional mixing device 2 moves downward to construct the mixing pile 53, and the enlarged head bidirectional mixing device 3 moves downward to construct the enlarged head 51; or the mixing pile bidirectional mixing device 2 moves downward to construct the mixing pile 53, and the enlarged head bidirectional mixing device 3 rotates in place or stops in place; or the mixing head bidirectional mixing device 2 rotates in place or stops in place when it reaches the predetermined depth, and the enlarged head bidirectional mixing device 3 moves downward to construct the enlarged head; until the mixing pile 51 constructed by the mixing pile bidirectional mixing device 2 reaches the predetermined depth, and the enlarged head 51 constructed by the enlarged head bidirectional mixing device 3 reaches the predetermined depth, at this time, at the connection between the enlarged head 51 and the mixing pile 53, the second mixing head 33, which includes multiple upper second vertical plates 33232 and multiple lower inclined plates 33233, stirs out the enlarged head 51 and the frustum transition section 52 connecting the mixing pile 53.

[0062] 4) Operation: Stop spraying grout at the spray nozzle 6, and keep the first power head 21, the first inner drill rod 221, the first outer drill rod 222, the first mixing head 23 and the drill bit 4 rotating. At the same time, keep the second power head 31, the second inner drill rod 321, the second outer drill rod 322 and the second mixing head 33 rotating. The mixing pile bidirectional mixing device 2 moves upward first, followed by the enlarged head bidirectional mixing device 3, or both devices, namely the mixing pile bidirectional mixing device 2 and the enlarged head bidirectional mixing device 3, move upward simultaneously until the drill bit 4, which is the lowest of the first power head 21, the second power head 31, the second mixing head 33, the first mixing head 23 and the drill bit 4 arranged from top to bottom, is lifted above the ground. Then, turn off the power supply to the winch mechanism 14 and the first power head 21 and the second power head 31.

[0063] The walking mechanism is moved laterally and steps 1)-4) are repeated. After the construction of one row of mixing piles 53 with enlarged heads 51 is completed, the piles are moved longitudinally backward and steps 1)-4) are repeated to construct the second row of mixing piles 53 with enlarged heads 51. Then, mixing piles 53 with enlarged heads 51 are constructed row by row until the reinforcement treatment of the soft soil foundation for anti-settlement is completed piece by piece.

[0064] Figure 5 It is convenient to display and occupies a small area on the drawing. In fact, the construction of the mixing piles 53 with enlarged heads 51 in rows can be carried out in conjunction with... Figure 5 Conversely, as shown, the pile driver 1 is positioned outside the already constructed enlarged head 51, frustum transition section 52, and mixing pile 53, as if... Figure 5 The front side as shown.

[0065] In step 2), the first power head 21 drives the first inner drill rod 221 and drives the drill bit 4 to drill down and drives the first inner transverse mixing blade 231 of the first mixing head 23. At the same time, it drives the first outer drill rod 222 and drives the first mixing frame 232 and the first outer transverse mixing blade 233 of the first mixing head 23 to mix the cement and soil in both directions.

[0066] In step 2), the second power head 31 drives the second inner drill rod 321 and drives the second inner transverse mixing blade 331 of the second mixing head 33, while simultaneously driving the second outer drill rod 322 and driving the second mixing frame 332 and the second outer transverse mixing blade 333 of the second mixing head 33 to mix the cement and soil in both directions.

[0067] Components, structures, or quantities not marked above are not shown in the drawings, and some components are not marked in the drawings. The drawings are for illustrative purposes only. In case of any inconsistency between the drawings and the text description, or between the drawings themselves, the text description shall prevail.

[0068] The above description is merely a preferred embodiment of this utility model and is not intended to limit the utility model. Various modifications and variations can be made to this utility model by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this utility model should be included within the protection scope of this utility model.

Claims

1. A mixing pile for settlement prevention and reinforcement of soft soil foundations, characterized in that: The top is an enlarged head, the bottom of which is a downward-extending mixing pile. Between the enlarged head and the mixing pile is a frustum transition section, forming a mixing pile with an enlarged head and a frustum transition section. There are multiple rows of mixing piles with enlarged heads and frustum transition sections, with multiple piles in each row. There are gaps between adjacent enlarged heads, or adjacent enlarged heads are tangent to each other, or adjacent enlarged heads interlock with each other.

2. The mixing pile for settlement prevention and reinforcement of soft soil foundation according to claim 1, characterized in that: The enlarged heads of adjacent rows are arranged alternately.

3. The mixing pile for settlement prevention and reinforcement of soft soil foundation according to claim 2, characterized in that: The staggered arrangement structure is as follows: the diameter line of a circle of each enlarged head in a row is perpendicular to the line connecting the centers of two adjacent enlarged heads in the adjacent row, and the diameter line of this circle bisects the line connecting the centers.

4. The mixing pile for settlement prevention and reinforcement of soft soil foundation according to claim 1, characterized in that: The gap between adjacent enlarged heads is 1mm-50mm.

5. The mixing pile for settlement prevention and reinforcement of soft soil foundation according to claim 1, characterized in that: The aforementioned frustum transition section is either a smooth frustum transition section or a stepped frustum transition section.

Images