Special-shaped pipe pile and construction method of integrally-formed cement-soil stirring stiff composite pile

Abstract

A regular polygonal driving hole is formed in a pile body of the special-shaped pipe pile, and the driving hole and the pile body are coaxially arranged; a connecting bolt and a grouting pipe are embedded in the pile body, the connecting bolt extends out of the end face of the pile head in the first axis direction, a guniting hole is formed in the pile end, one end of the grouting pipe penetrates through the end face of the pile head, and the other end of the grouting pipe communicates with the guniting hole. A stirring blade is further arranged at the pile end; the special-shaped pipe pile is a prestressed pipe pile. The invention further discloses a construction method of the integrally-formed cement-soil stirring stiff composite pile. When the special-shaped pipe pile sinks, sinking and construction of the cement-soil mixing pile can be completed at a time, it is guaranteed that the cement-soil mixing pile and the special-shaped pipe pile are highly concentric, and harm caused by the soil squeezing effect is avoided. The stirring blades reserved underground improve the bearing capacity of the pile foundation, the length of the pile foundation can be shortened, and the economical efficiency of a project is improved.

Description

Technical Field

[0001] The invention relates to a special-shaped pipe pile and a construction method of an integrally formed cement-soil mixing rigid composite pile using the special-shaped pipe pile. Background Art

[0002] Since fish ponds, tidal flats and other areas are mostly deep soft soil foundations with low strength and large deformation, conventional prestressed concrete pipe piles are required as foundations, which require large diameter and long piles, resulting in great construction difficulty and high cost. Cement soil reinforced piles are a new type of rigid composite pile. Cement soil piles are first formed underground, and then small diameter concrete piles are pressed into the cement soil piles as the pile core to form cement soil reinforced piles.

[0003] The cement-soil reinforced pile has a larger pile-soil extrusion interface, which improves the load transfer path and presents the characteristics of a friction pile. The cement-soil pile has a much higher lateral resistance than the concrete pile, while the concrete pile has a much higher pile body strength than the cement-soil pile. The combination of the two can achieve a higher cost-effectiveness than the traditional pile type. At present, the cement-soil reinforced pile still has the following problems: the cement-soil pile and the pile core insertion are two different construction processes. During the construction, multiple equipments need to be cross-operated, resulting in many construction processes, cumbersome construction, long construction period and high cost; the process of inserting the concrete pile will easily cause soil squeezing problems, resulting in the damage of adjacent piles and adjacent buildings; during the construction process, it is difficult to ensure that the concrete pile is inserted along the pile core of the cement-soil pile, resulting in the phenomenon that the concrete pile and the cement-soil pile are not concentric, which greatly reduces the bearing capacity of the cement-soil reinforced pile. The above problems are particularly serious when constructing in areas such as fish ponds and tidal flats. Therefore, improving the construction technology of cement-soil reinforced piles in soft soil foundation areas such as fish ponds and tidal flats still has strong practical significance. Summary of the invention

[0004] In order to solve the above-mentioned problems of cement-soil reinforced piles, the present application first proposes a special-shaped pipe pile, which includes a circular pile body, the opposite ends of the pile body are respectively formed as a pile head and a pile end, when the special-shaped pipe pile is sunk into the ground, the pile head faces upward and the pile end faces downward; the central axis of the pile body extends along the first axis direction, and a driving hole is provided in the pile body, the driving hole penetrates the end face of the pile head along the first axis direction, the driving hole is a regular polygon, and the driving hole is coaxially arranged with the pile body; connecting bolts and grouting pipes are pre-embedded in the pile body, the connecting bolts extend out of the end face of the pile head along the first axis direction, a grouting hole is arranged at the pile end, one end of the grouting pipe penetrates the end face of the pile head along the first axis direction, and the other end of the grouting pipe is connected to the grouting hole; a stirring blade is also arranged at the pile end; the special-shaped pipe pile is a prestressed pipe pile.

[0005] The grouting pipe is prefabricated in the pile body of the special-shaped pipe pile, which can directly form a cement soil mixing pile on the periphery of the special-shaped pipe pile during the sinking process of the special-shaped pipe pile, completing the sinking of the special-shaped pipe pile and the construction of the cement soil mixing pile at one time, improving the construction efficiency while ensuring the high concentricity of the cement soil mixing pile and the special-shaped pipe pile. Compared with the rigid composite pile formed by the conventional post-insertion method of prestressed concrete pipe piles, there is no harm caused by the soil squeezing effect.

[0006] Since the grouting pipe and the grouting hole are prefabricated in the pile body, the secondary setting of the grouting pipe is avoided, thus reducing the overall construction cost.

[0007] Since stirring blades are provided at the ends of the special-shaped pipe piles, the stirring blades remain underground after the construction is completed, which can effectively improve the bearing capacity of the pile foundation, especially the compressive bearing capacity, and thereby shorten the length of the pile foundation and improve the economy of the project; especially in the soft foundations of projects such as fish-photovoltaic complementary and tidal flat photovoltaic, it is more practical.

[0008] Furthermore, a central hole extending along the first axis is provided in the pile body, the central hole is connected to the driving hole, and one end of the central hole facing the pile end is a closed end. After the central hole is provided, the weight of the special-shaped pipe pile can be reduced, and the amount of raw materials such as cement can be reduced, so as to reduce the production cost of the special-shaped pipe pile. The production of the pile body can directly adopt the existing construction process of the pipe pile.

[0009] In order to smoothly adopt the existing pipe pile production process, the center hole of the special-shaped pipe pile is circular.

[0010] Secondly, the present application also discloses a construction method of an integrally formed cement-soil mixing rigid composite pile, which comprises the following steps:

[0011] (1) The output shaft of the power head of the rotary pile driver is detachably connected to the pile head of any of the above-mentioned special-shaped pipe piles via a connecting portion, wherein the connecting portion includes a rotary joint, the liquid outlet of the rotary joint is connected to the grouting pipe, and the liquid inlet of the rotary joint is connected to the grouting equipment;

[0012] (2) Start the rotary pile driver to rotate and sink the special-shaped pipe pile at the set position, and at the same time, introduce cement slurry into the grouting pipe through the rotary joint, and the cement slurry is sprayed out through the spraying hole and mixed with the underground soil to form cement soil;

[0013] (3) When the special-shaped pipe pile sinks to the set depth, the connection part is removed from the special-shaped pipe pile that has been completely sunk, and the construction of a cement-soil mixing rigid composite pile is completed. The rotary pile driver can also be called a rotary pile driver.

[0014] In the present application, the cement-soil mixing rigid composite piles formed include special-shaped pipe piles and cement-soil mixing piles wrapped around the special-shaped pipe piles. The cement-soil mixing piles are used to achieve a reinforcement effect, thereby increasing the pile end resistance and pile side friction. Since the cement-soil pile body is implanted by rotation, rather than the traditional static pressure sinking, the ground endurance requirements for the construction site are relatively low, and there is no need to pre-treat the weak areas of the topsoil layer. It is easy to construct in new fill, silt soil, and sites soaked in water. Therefore, for soft foundations in projects such as fish-light complementarity and tidal flat photovoltaics, the pile foundation bearing capacity, especially the compressive bearing capacity, can be effectively improved, the pile foundation length can be shortened, and the project's economy can be effectively improved.

[0015] The present application adopts a rotational method to implant the special-shaped pipe piles into the soil layer, which not only increases the solidification contact area between the pile body and the cement soil layer, but also the stirring blades are located at the lower end of the pile body, which can greatly improve the vertical compression and pull-out resistance of the pile foundation.

[0016] In addition, since the drilling of the special-shaped pipe piles and the construction of the cement-soil mixing piles are carried out simultaneously in the present application, the construction efficiency is improved while the high concentricity of the cement-soil mixing piles and the special-shaped pipe piles can be ensured. Compared with the rigid composite piles formed by the conventional post-insertion method of prestressed concrete pipe piles, there is no harm caused by the soil squeezing effect.

[0017] Specifically, the connection portion includes a pile body connection head and the rotary joint connected together by bolts;

[0018] The rotary joint comprises an inner tube and an outer tube rotatably sleeved on the outer circumference of the inner tube, the two ends of the outer tube are sealingly connected to the inner tube, an annular cavity is formed between the inner tube and the outer tube, a liquid inlet hole communicating with the annular cavity and the inner cavity of the inner tube is provided on the tube wall of the inner tube, and a liquid inlet communicating with the annular cavity is provided on the outer tube; and a connecting ear is provided on the outer tube, and the connecting ear is fixedly connected to the fixed component of the rotary pile driver; one end of the inner tube is detachably connected to the output shaft of the power head, and the other end of the inner tube is bolted to the pile body connector, and the inner cavity of the inner tube is formed as a liquid outlet at one end facing the pile body connector.

[0019] Since the pile body connector and the rotary joint are connected together by bolts, they can be easily disassembled, so as to facilitate the disassembly, maintenance and cleaning of the rotary joint. The rotary joint can be used to conveniently input cement slurry into the grouting pipe in the pile body.

[0020] Specifically, the pile body connector includes a rod body and a rod body flange, the rod body extends along the first axial direction, the rod body flange is fixed to the middle part of the rod body in the first axial direction, and the rod body flange divides the rod body into a slurry outlet part and a driving part; an end flange is fixedly installed at one end of the slurry outlet part away from the driving part, and a slurry hole is arranged in the slurry outlet part, the slurry hole passes through the end surface of the slurry outlet part away from the driving part, and the liquid outlet of the rotary joint is connected to the grouting pipe through the slurry hole; the pile body connector is connected to the rotary joint through the end flange;

[0021] The driving part has an outer circumference with the same shape as the inner circumference of the driving hole. The pile body connector is detachably mounted on the pile head of the special-shaped pipe pile via the rod body flange. The driving part is inserted into the driving hole and can drive the special-shaped pipe pile to rotate.

[0022] Since the driving part of the rod body has the same shape as the driving hole, it can transmit greater power and apply the power transmitted by the rotary joint to the pile body to drive the special-shaped pipe pile to rotate and sink. The rod body flange mainly plays the role of lifting the special-shaped pipe pile. Of course, the rod body flange also has the function of transmitting power.

[0023] The driving unit is utilized to avoid the pile driver from using a clamping method to sink special-shaped pipe piles. When the static pressure sinking method is used to construct pipe piles, a holding pressure method is required, and the pile driver needs to use a larger clamping force to clamp the pipe piles. In the actual construction process, excessive clamping force is often used to clamp the pipe piles, which can easily cause cracks in the pipe piles. In severe cases, the pile body will be crushed, resulting in a waste of the pipe piles. When the pipe piles are sunk by simply pressing down or hammering, the pipe piles are prone to tilting and breaking. The present application utilizes the cooperation of the driving unit and the driving hole, which can stably transmit torque while transmitting downward force, thereby ensuring uniform force on the pile body. Due to the stirring effect of the stirring blades, the downward force when the special-shaped pipe piles sink is reduced.

[0024] Furthermore, in order to smoothly deliver cement slurry into the grouting pipe, a slurry hole connected to the slurry hole is provided on the outer wall of the slurry hole, a pipe hole is provided on the rod flange, one end of the external pipe is connected to the slurry hole, and the other end of the external pipe is connected to the grouting pipe after passing through the pipe hole. There are no specific requirements for the structure of the external pipe, as long as the slurry hole can be smoothly connected to the grouting pipe. The pipe connection method in the prior art can meet the needs of this application and can be set according to specific needs, which will not be repeated.

[0025] Furthermore, to facilitate operation and working, the connecting ear can be detachably connected to the housing of the power head.

[0026] Specifically, in step (2), the grouting pressure of the cement slurry is 0.5-5.0 MPa. Under the above grouting pressure, cement soil mixing piles can be smoothly formed synchronously on the periphery of the special-shaped pipe piles. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is a structural schematic diagram of an embodiment of the special-shaped pipe pile in the application.

[0028] Figure 2 yes Figure 1 Top view of the .

[0029] Figure 3 yes Figure 1 Center AA view.

[0030] Figure 4 It is a status diagram of the construction of cement-soil mixed rigid composite piles.

[0031] Figure 5 yes Figure 4 Enlarged view of part B.

[0032] Figure 6 It is a schematic diagram of the pipe pile connector.

[0033] Figure 7 yes Figure 6 Top view of the .

[0034] Figure 8 yes Figure 6 View from CC.

[0035] Fig. 9 It is a structural diagram of a rotary joint. DETAILED DESCRIPTION

[0036] Example 1

[0037] The structure of the special-shaped pipe pile 10 is first described below. Figure 1-Figure 3 , the direction of the arrow Z in the accompanying drawings indicates the direction of the first axis.

[0038] The special-shaped pipe pile 10 is a prestressed pipe pile, which includes a circular pile body 11, and the opposite ends of the pile body are respectively formed into a pile head 111 and a pile end 112. When the special-shaped pipe pile 10 is sunk into the ground, the pile head 111 faces upward and the pile end 112 faces downward. The central axis 113 of the pile body 11 extends along the first axis direction, and there is a driving hole 121 in the pile body. The driving hole 121 passes through the end face of the pile head along the first axis direction. The driving hole is square and is coaxially arranged with the pile body. It can be understood that in other embodiments, the driving hole can also be in the shape of an equilateral triangle, a regular hexagon, etc. A pile body flange 17 is prefabricated at the end of the pile head of the pile body 11 according to conventional design.

[0039] A connecting bolt 14 and a grouting pipe 13 are pre-buried in the pile body, the connecting bolt 14 extends out of the pile body flange along the first axis direction, a grouting hole 16 is provided at the pile end, one end of the grouting pipe 13 penetrates the end face of the pile head along the first axis direction, and the other end of the grouting pipe is connected to the grouting hole 16. The grouting hole penetrates the outer surface of the pile body outwardly, and the cement slurry entering the grouting pipe can be sprayed outward through the grouting hole.

[0040] A slurry pipe hole 171 is provided on the flange of the pile body, and the grouting pipe is aligned with the slurry pipe hole. The slurry pipe hole is used for the external pipeline to connect the grouting pipe so that the cement slurry can enter the grouting pipe. A stirring blade 15 is also provided at the pile end. In this embodiment, a steel plate is pre-embedded in the pile end, and the stirring blade is a steel part. After the production of the pile body is completed, the stirring blade is welded to the pre-embedded steel plate.

[0041] The pile body 11 has a central hole 12 extending along the first axis, the central hole 12 is connected to the driving hole 121, and the end of the central hole facing the pile end is a closed end. In this embodiment, the central hole 12 is circular and coaxial with the driving hole 121.

[0042] Example 2

[0043] See also Figure 4 and Figure 5 The following is an explanation of the construction method of the one-piece cement-soil mixing rigid composite pile, which includes the following steps:

[0044] (1) The output shaft of the power head 51 of the rotary pile driver 90 is detachably connected to the pile head of the above-mentioned special-shaped pipe pile 10 via a connecting portion, and the connecting portion includes a rotary joint 30 and a pile body connecting head 20 connected together. The power head 51 is carried by the rotary pile driver itself and is an existing mature technology, which will not be described in detail. Figure 4 , reference numeral 100 denotes the ground.

[0045] See also Fig. 9In this embodiment, the rotary joint 30 includes an inner tube 31 and an outer tube 32 rotatably sleeved on the outer circumference of the inner tube. An upper step 314 and a lower step surface 313 are provided on the outer circumferential surface of the inner tube 31. The upper step surface and the lower step surface are formed by radial depression of the outer circumferential surface of the inner tube, wherein the upper step surface is located above the lower step surface, and both the upper step surface and the lower step surface face upward. The inner ring of the lower angular contact bearing 331 is supported on the lower step surface, and the inner ring of the upper angular contact bearing 332 is supported on the upper step surface. A pressing step surface 326 is provided on the inner circumferential surface of the lower end of the outer tube 32, and the outer tube is supported on the upper surface of the outer ring of the lower angular contact bearing through the pressing step surface. The lower end cover 341 is fixed to the lower end of the outer tube 32 by bolts and presses against the lower surface of the outer ring of the lower angular contact bearing. An extrusion ring 351 is sleeved on the inner tube and a locking nut 352 is screwed on it. The extrusion ring 351 presses against the upper surface of the inner ring of the upper angular contact bearing, and the locking nut presses the extrusion ring 351 tightly against the inner ring of the upper angular contact bearing. The upper end cover 342 is fixed to the upper end of the outer tube 32 by bolts and presses against the lower surface of the outer ring of the upper angular contact bearing.

[0046] An annular cavity 323 is formed between the inner tube and the outer tube. To prevent cement slurry from entering the gap between the upper angular contact bearing and the lower angular contact bearing, two sealing rings 36 are installed in the annular cavity, and the two sealing rings are respectively close to the upper angular contact bearing and the lower angular contact bearing. A liquid inlet 312 is provided on the wall of the inner tube 31, which is connected to the annular cavity and the inner cavity 311 of the inner tube. A liquid inlet 321 is provided on the outer tube 32, which is connected to the annular cavity. The slurry inlet pipe 322 is welded to the outer tube and connected to the liquid inlet 321. In the vertical direction, the liquid inlet hole and the liquid inlet are located between the two sealing rings.

[0047] The outer tube is provided with a connecting ear 324, which is fixedly connected to the fixed component of the rotary pile driver. Specifically in this embodiment, the connecting ear 324 is connected to the outer shell of the power head 51 via a connecting plate 325, and the two ends of the connecting plate are respectively fixed to the connecting ear and the outer shell of the power head 51 by bolts, so that the connecting ear can be detachably connected to the outer shell of the power head.

[0048] An upper flange 372 is detachably mounted on the top of the inner tube by upper bolts 3721, and a lower flange 371 is welded on the bottom of the inner tube. One end of the inner cavity of the inner tube facing the pile body connector is formed as a liquid outlet 315.

[0049] See also Figure 6-Figure 8In this embodiment, the pile body connector 20 is made of steel structure as a whole. The pile body connector 20 specifically includes a rod body 21 and a rod body flange 25. The rod body extends along the first axis direction. The rod body flange is fixed to the middle part of the first axis direction of the rod body. The rod body flange 25 divides the rod body 21 into a slurry outlet portion 211 and a driving portion 212. A flange hole 251 is provided on the rod body flange 25. An end flange 24 is fixedly installed at one end of the slurry outlet portion 211 away from the driving portion 212, and a slurry hole 22 is provided in the slurry outlet portion. The slurry hole 22 passes through the end surface of the slurry outlet portion away from the driving portion. A slurry hole 23 is provided on the outer wall of the slurry hole, and a short tube 28 is screwed into the slurry hole 23 in a threaded manner.

[0050] An adapter 52 is fixedly mounted on the output shaft of the power head, and the upper flange is detachably connected to the adapter via bolts, and the rotary joint is connected to the output shaft of the power head via the adapter. The lower flange is detachably connected to the end flange 24 via bolts, and the rotary joint and the pile body connector 20 are connected together, so that the liquid outlet of the rotary joint is connected to the slurry hole 22.

[0051] In this embodiment, the driving part 212 has an outer peripheral surface of the same shape as the inner peripheral surface of the driving hole 121, the driving part 212 is inserted into the driving hole, and the flange hole 251 of the rod body flange is sleeved on the connecting bolt 14, the connecting nut 141 is screwed on the connecting bolt, and the pile body connector 20 is detachably fixed on the pile head of the special-shaped pipe pile, and the driving part can drive the special-shaped pipe pile to rotate. A pipe penetration hole 252 is provided on the rod body flange, and when the rod body flange is connected to the pile body, the pipe penetration hole is opposite to the slurry pipe hole 171 up and down.

[0052] An internal thread is provided on one end of the grouting pipe located at the pile head. The short pipe 29 is screwed on the internal thread after passing through the pipe hole and the grouting pipe hole in sequence. The short pipe 28 is connected to the short pipe 29 via a flexible joint 281, so that the grouting hole 22 is connected to the grouting pipe. Thus, the liquid outlet of the rotary joint is connected to the grouting pipe through the grouting hole 22. The short pipe 28, the short pipe 29 and the flexible joint 281 together constitute an external pipe. When working, the grouting pipe 322 is connected to the cement slurry pipeline 53 of the grouting equipment, so that the liquid inlet of the rotary joint is connected to the grouting equipment.

[0053] (2) Start the power head 51 of the rotary pile driver, rotate and sink the special-shaped pipe pile at the set position, and at the same time, introduce cement slurry into the grouting pipe through the rotary joint, and the cement slurry is sprayed out through the spraying hole and mixed with the underground soil to form cement soil. The grouting pressure of the cement slurry is 4MPa.

[0054] (3) When the special-shaped pipe pile sinks to a set depth, the connecting part is removed from the special-shaped pipe pile that has been completely sunk, thereby completing the construction of a cement-soil mixing rigid composite pile.

[0055] The formed cement-soil mixing rigid composite piles include special-shaped pipe piles and cement-soil mixing piles wrapped around the special-shaped pipe piles. The cement-soil mixing piles are used to achieve a reinforcement effect, thereby increasing the pile end resistance and pile side friction. For soft foundations in projects such as fish-light complementary and tidal flat photovoltaic projects, the bearing capacity of the pile foundation can be effectively improved, especially the compressive bearing capacity, and the length of the pile foundation can be shortened, effectively improving the economy of the project.

[0056] The present application adopts a rotational method to implant the special-shaped pipe piles into the soil layer, which not only increases the solidification contact area between the pile body and the cement soil layer, but also the stirring blades are located at the lower end of the pile body, which can greatly improve the vertical compression and pull-out resistance of the pile foundation.

[0057] In addition, since the drilling of special-shaped pipe piles is carried out simultaneously with the construction of cement-soil mixing piles, the construction efficiency can be improved while ensuring the high concentricity of cement-soil mixing piles and special-shaped pipe piles. Compared with the rigid composite piles formed by the conventional post-insertion method of prestressed concrete pipe piles, there is no harm caused by the soil squeezing effect.

Claims

1. A special-shaped pipe pile, characterized in that: It comprises a circular pile body, the opposite ends of which are respectively formed as a pile head and a pile end. When the special-shaped pipe pile is sunk into the ground, the pile head faces upward and the pile end faces downward. The central axis of the pile body extends along the first axis direction. A driving hole is provided in the pile body. The driving hole penetrates the end face of the pile head along the first axis direction. The driving hole is a regular polygon and is coaxially arranged with the pile body. Connecting bolts and grouting pipes are pre-embedded in the pile body. The connecting bolts extend out of the end face of the pile head along the first axis direction. A grouting hole is provided at the pile end. One end of the grouting pipe penetrates the end face of the pile head along the first axis direction, and the other end of the grouting pipe is connected to the grouting hole. A stirring blade is also provided at the pile end. The special-shaped pipe pile is a prestressed pipe pile.

2. The special-shaped pipe pile according to claim 1, characterized in that: A central hole extending along the first axis direction is provided in the pile body, the central hole is connected to the driving hole, and one end of the central hole facing the pile end is a closed end.

3. The special-shaped pipe pile according to claim 2, characterized in that: The central hole is circular.

4. A construction method for an integrally formed cement-soil mixing rigid composite pile, characterized in that: The steps include: (1) The output shaft of the power head of the rotary pile driver is detachably connected to the pile head of the special-shaped pipe pile according to any one of claims 1 to 3 via a connecting portion, wherein the connecting portion comprises a rotary joint, the liquid outlet of the rotary joint is connected to the grouting pipe, and the liquid inlet of the rotary joint is connected to the grouting equipment; (2) Start the rotary pile driver to rotate and sink the special-shaped pipe pile at the set position, and at the same time, introduce cement slurry into the grouting pipe through the rotary joint, and the cement slurry is sprayed out through the spraying hole and mixed with the underground soil to form cement soil; (3) When the special-shaped pipe pile sinks to a set depth, the connecting part is removed from the special-shaped pipe pile that has been completely sunk, thereby completing the construction of a cement-soil mixing rigid composite pile.

5. The construction method according to claim 4, characterized in that: The connection part comprises a pile body connection head and the rotary joint connected together by bolts; The rotary joint comprises an inner tube and an outer tube rotatably sleeved on the outer circumference of the inner tube, the two ends of the outer tube are sealingly connected to the inner tube, an annular cavity is formed between the inner tube and the outer tube, a liquid inlet hole communicating with the annular cavity and the inner cavity of the inner tube is provided on the tube wall of the inner tube, and a liquid inlet communicating with the annular cavity is provided on the outer tube; and a connecting ear is provided on the outer tube, and the connecting ear is fixedly connected to the fixed component of the rotary pile driver; one end of the inner tube is detachably connected to the output shaft of the power head, and the other end of the inner tube is bolted to the pile body connector, and the inner cavity of the inner tube is formed as a liquid outlet at one end facing the pile body connector.

6. The construction method according to claim 5, characterized in that: The pile body connector includes a rod body and a rod body flange, the rod body extends along the first axial direction, the rod body flange is fixed to the middle part of the rod body in the first axial direction, and the rod body flange divides the rod body into a slurry outlet part and a driving part; an end flange is fixedly installed at one end of the slurry outlet part away from the driving part, and a slurry hole is arranged in the slurry outlet part, the slurry hole passes through the end surface of the slurry outlet part away from the driving part, and the liquid outlet of the rotary joint is connected to the grouting pipe through the slurry hole; the pile body connector is connected to the rotary joint through the end flange; The driving part has an outer peripheral surface with the same shape as the inner peripheral surface of the driving hole. The pile body connecting head is installed on the pile head of the special-shaped pipe pile through the rod body flange. The driving part is inserted into the driving hole and can drive the special-shaped pipe pile to rotate.

7. The construction method according to claim 6, characterized in that: A slurry hole connected to the slurry hole is arranged on the outer wall of the slurry hole, a pipe hole is arranged on the rod body flange, one end of the external pipe is connected to the slurry hole, and the other end of the external pipe passes through the pipe hole and is connected to the grouting pipe.

8. The construction method according to claim 5, characterized in that: The connecting ear is detachably connected to the housing of the power head.

9. The construction method according to claim 4, characterized in that: In step (2), the grouting pressure of the cement slurry is 0.5-5.0 MPa.

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