Construction method of prefabricated hollow core reinforced pile with inner and outer spreading wings

Abstract

The application provides a prefabricated hollow core reinforced pile construction method with inner and outer wings, and belongs to the field of prefabricated hollow core reinforced pile construction. The method comprises a reinforced pile body and a wing expansion device. A plurality of expansion units are arranged along the axial direction of the reinforced pile body. Each expansion unit is circularly arranged along the center line of the reinforced pile body and comprises a plurality of wings. During construction, a hole is first opened on the ground, and slurry is injected into the hole. Then, the reinforced pile body, in which the wings are temporarily fixed by iron sheets to an unfolded state and the bottom is closed, is placed in the hole, so that the slurry wraps the reinforced pile body on the outside. The wing expansion device is lowered into the hollow part of the reinforced pile body to the uppermost position of the wings. The uppermost wings block the wing expansion device from continuing to be lowered. At this time, the wing expansion device is opened to push the wings outwards towards the outer wall of the reinforced pile body. Then, the wing expansion device continues to be lowered, and the above steps are repeated to sequentially push the wings outwards towards the outer wall of the reinforced pile body from top to bottom.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of prefabricated hollow core strength pile construction, and particularly relates to a prefabricated hollow core strength pile construction method with inner and outer wings. BACKGROUND

[0002] As a form of deep foundation, pile foundation is widely used in the fields of construction, bridge, port, wharf, wind power, offshore platform and the like. The main role of the pile foundation is to transfer the load of the upper structure to the deep soil or rock layer with high bearing capacity, so as to meet the requirements of the structure on bearing capacity, settlement control and stability. Especially in soft soil foundation, earthquake-prone areas, high-load structures and projects requiring resistance to horizontal forces (such as wind force, wave force, ship impact force), the pile foundation plays an irreplaceable role.

[0003] The Chinese invention patent with the publication number "CN112359830A" discloses "a prefabricated hollow pile pipe flap type pile shoe and construction method". In the construction, the flap type pile shoe assembly is welded at the bottom of the hollow pipe pile, ensuring that the flap is closed into a cone shape, and the cone tip is located at the center of the pile bottom, with a position error of not more than 20 mm. Then, the hollow pile pipe with the flap assembly is placed at the designated pile position by using a lifting device. After that, the hammering or static pressure equipment is started to sink the hollow pile pipe to the designed stratum and load value reaches 80% of the load loading design value, and the pile sinking is stopped. The steel pipe is used to hammer the wedge-shaped plug on the ground to open the multiple flaps, and then the static pressure equipment is started for secondary pile pressing of the hollow pile pipe, and the load is loaded to 100% of the load loading design value. The static pressure equipment is shifted, the site is cleaned, and the concrete is poured and vibrated at the bottom of the pile pipe. The concrete pouring range should be 0.5-1 meters higher than the flap type pile shoe, and the pile bottom enlarged head is formed to complete the construction of the prefabricated hollow pile pipe flap type pile shoe. However, when the steel pipe hammers the wedge-shaped plug, the distance of the flap rotating outward from the center is limited by the size of the inner diameter of the hollow pipe pile, and the maximum distance can only equal to the radius of the inner diameter of the hollow pipe pile. Therefore, the flap tip cannot reach the outer diameter of the pile from the pile center.

[0004] Therefore, the flap of the invention cannot rotate out of the outer diameter of the hollow pipe pile, so that the flap cannot be expanded under the hammering of the steel pipe, and the bottom expansion cannot be achieved. SUMMARY

[0005] In view of the above-mentioned disadvantages of the prior art, the purpose of the present application is to provide a prefabricated hollow core strength pile construction method with inner and outer wings, which solves the problem that the hollow pipe pile cannot be expanded in the prior art.

[0006] To achieve the above-mentioned purposes and other related purposes, the present application provides a prefabricated hollow core strength pile construction method with inner and outer wings, which comprises:

[0007] Pore-forming step: drilling a hole on the ground and injecting slurry into the hole;

[0008] Pile-putting step: placing a prefabricated hollow core reinforced pile into the hole, with the slurry wrapping the prefabricated hollow core reinforced pile on the outside, and the hollow part of the prefabricated hollow core reinforced pile remaining dry;

[0009] Expansion step: lowering a wing expansion device from the prefabricated hollow core reinforced pile to the wing at the uppermost position, and the uppermost wing will block the wing expansion device from continuing to be lowered, at which point the wing expansion device is turned on, the wing expansion device pushes the wing outwards towards the outer wall of the prefabricated hollow core reinforced pile, and then the wing expansion device continues to be lowered, and the above steps are repeated to sequentially push the wings outwards towards the outer wall of the prefabricated hollow core reinforced pile from top to bottom.

[0010] As an optional solution, in the pile-putting step, the prefabricated hollow core reinforced pile comprises:

[0011] A reinforced pile body, the upper and lower end faces of the reinforced pile body are penetrated by a first through hole;

[0012] A plurality of expansion units are arranged in the axial direction of the reinforced pile body, each expansion unit comprises a plurality of expansion modules, the plurality of expansion modules are circularly arranged along the center line of the reinforced pile body, each expansion module comprises a wing and a second through hole, the second through hole is provided on the reinforced pile body, the second through hole penetrates the inner and outer sidewalls of the reinforced pile body, the wing is in the shape of a sector, the wing is rotatably installed in the second through hole, the rotation axis of the wing is perpendicular to the center line of the reinforced pile body, and the rotation axis of the wing is located in the second through hole;

[0013] When the wing is not unfolded, part of the wing is located inside the reinforced pile body;

[0014] During the process of rotating the wing to the unfolded state, the wing continuously closes the second through hole, and part of the wing is located outside the reinforced pile body.

[0015] As an optional solution, the upper end face of the wing is in the shape of a circular arc, and the central axis of the upper end face of the wing coincides with the rotation axis of the wing;

[0016] The upper end face of the second through hole is fitted with the upper end face of the wing.

[0017] As an optional solution, the expansion module further comprises a mounting groove, a first spring, a limiting block and a limiting groove;

[0018] The mounting groove is arranged at the lower end surface of the second through hole, one end of the first spring is fixedly connected to the lower end of the mounting groove, and the other end of the first spring is fixedly connected to the limiting block.

[0019] The rotating axis of the supporting wing is located at the upper portion of the second through hole, and a limiting groove is arranged at the lower end surface of the supporting wing, and when the supporting wing rotates to the unfolded state in the second through hole, the limiting block extends into the limiting groove under the action of the first spring.

[0020] As an optional solution, the lower end surface of the second through hole is an arc surface.

[0021] The lower end surface of the second through hole is in abutment with the lower end surface of the supporting wing.

[0022] As an optional solution, when the supporting wing is not unfolded, the maximum distance value of the supporting wing extending into the first through hole is z.

[0023] The cross section of the first through hole is a square, and one end surface of the supporting wing is in abutment with one side wall of the square first through hole.

[0024] The side wall of the square first through hole in abutment with the supporting wing is a first side wall, and the side wall of the square first through hole parallel to the first side wall is a second side wall.

[0025] The distance between the other end surface of the supporting wing and the second side wall is greater than or equal to z.

[0026] As an optional solution, in the step of placing, the bottom of the prefabricated hollow core steel pile is closed before the prefabricated hollow core steel pile is placed in the hole.

[0027] As an optional solution, in the step of expanding, the supporting wing expanding device comprises a first mounting frame, a second mounting frame, a telescopic power source and a plurality of articulated modules.

[0028] The fixed end of the telescopic power source is fixedly installed on the first mounting frame, the extending end of the telescopic power source is fixedly installed on the second mounting frame, and the first mounting frame is located above the second mounting frame.

[0029] When the supporting wing expanding device is placed in the steel pile body, the axial direction of the telescopic power source coincides with the center line of the steel pile body.

[0030] A plurality of said hinge modules are circularly arrayed along the axial direction of the telescopic power source, each of said hinge modules comprises a first rotating block and a second rotating block, one end of said first rotating block is hingedly connected to the first mounting frame, the other end of said first rotating block is hingedly connected to one end of said second rotating block, the other end of said second rotating block is hingedly connected to the second mounting frame, said first rotating block and said second rotating block push the wings towards the outer wall of the body of the stiff pile under the action of the telescopic power source.

[0031] As an option, said wing expansion device further comprises a transverse limiting rod;

[0032] Said transverse limiting rod is fixedly installed on the upper end surface of the first mounting frame, the length direction of said transverse limiting rod is perpendicular to the axial direction of the telescopic power source, and the length of said transverse limiting rod is the same as the length of the diagonal line of the first through hole;

[0033] When the wing expansion device is placed in the body of the stiff pile, the two ends of the length direction of said transverse limiting rod are provided with mutually perpendicular surfaces, and the mutually perpendicular surfaces of the two ends of the length direction of said transverse limiting rod are in close contact with the two side walls of the first through hole corresponding to the adjacent two sides.

[0034] As an option, said wing expansion device further comprises a vertical limiting rod;

[0035] The lower end of said vertical limiting rod is fixedly installed on one end of the length direction of the transverse limiting rod, and the length direction of said vertical limiting rod is perpendicular to the length direction of the transverse limiting rod;

[0036] When the wing expansion device is placed in the body of the stiff pile, two side walls of said vertical limiting rod are in close contact with the two side walls of the first through hole.

[0037] As described above, the prefabricated hollow stiff pile construction method with inner and outer wings has at least the following beneficial effects:

[0038] 1. After the existing prefabricated pile is sunk, the self-weight stress of the soil body is large, the pressure of the deep soil is large, and the wings on the pile body cannot be expanded into the deep soil. The construction process of the stiff pile body is used in the present application, the horizontal section of the soil layer is in turn the original soil, the slurry, and the stiff pile body. When the stiff pile body with fixed wings and a closed bottom is placed in the hole, the central axis of the stiff pile body coincides with the central axis of the hole, and the outer side wall of the stiff pile body leaves a space filled with slurry with the inner side wall of the hole. When the wing expansion device pushes the wings towards the outer wall of the stiff pile body, the part of the wings pushed out of the stiff pile body is wrapped by the slurry, and at this time the slurry has not completely solidified, so that the wings can be smoothly pushed out of the stiff pile body and come into contact with the original soil. After the slurry solidifies, the stiff pile body forms an expanded bottom, thereby solving the problem of uplift resistance.

[0039] 2. When existing hollow pipe piles have multiple supports along the axial direction, after all the supports are opened from top to bottom using an extension device, the upper supports will return to their partial position inside the hollow pipe pile when the lower supports are opened. When the extension device is removed from the bottom, it will be blocked by the upper supports, preventing it from being removed from the bottom of the hollow pipe pile. However, the support wing extension device of this invention pushes the supports towards the outer wall of the rigid pile body. After the limit block extends into the limit groove under the action of the first spring, the supports are automatically fixed in the extended state. This means that the support wing extension device does not need to keep the extended supports in the extended state, and the supports will not return to their partial position inside the rigid pile body. This ensures that the support wing extension device will not be blocked by the upper supports when removed from the bottom, and the support wing extension device can be smoothly removed from the bottom of the rigid pile body. The structural design is ingenious.

[0040] 3. The support wings of the present invention are arranged in an array along the axial direction of the rigid pile body. When the rigid pile body with the support wings fixed and the bottom closed is placed in the hole, since the support wings are installed in the axial direction of the rigid pile body from top to bottom, the rigid pile body can be rotated to the unfolded state (i.e., a part of the area is outside the rigid pile body) from top to bottom during subsequent construction to improve the bearing capacity of the rigid pile body. The structure is ingeniously designed and the overall stability of the rigid pile body after construction is good.

[0041] 4. In this invention, when the support wing is not deployed, a portion of the support wing is located within the rigid pile body. After the support wing extension device is lowered into the rigid pile body, the portion of the support wing located within the rigid pile body will position the support wing extension device. That is, when the support wing extension device is lowered to contact the portion of the support wing located within the rigid pile body, the support wing extension device cannot be lowered further due to the obstruction of the support wing. At this point, it can be known that the support wing extension device has been lowered to the working position. That is, at this time, the support wing can be accurately pushed out towards the outer wall of the rigid pile body through the support wing extension device. The structure is cleverly coordinated.

[0042] 5. This invention can control the distance between the support wing and the second sidewall to adjust the area of ​​the support wing located outside the rigid pile body when the support wing rotates from the undeployed state to the deployed state. When the support wing is not deployed, the maximum distance the support wing extends into the first through hole is z. When the distance between the support wing and the second sidewall is equal to z, the area of ​​the support wing located outside the rigid pile body is the largest when the support wing rotates from the undeployed state to the deployed state. At this time, the bearing capacity of the support wing is the best, thereby maximizing the stability of the rigid pile body by adjusting the distance between the wing and the second sidewall.

[0043] 6、The present application is placed in the hole after the temporary fixing of the wing and the bottom of the closed body of the stiff pile, the wing part is located in the stiff pile body, when the wing expansion device is put into the stiff pile body from the hinge of the first rotating block and the second rotating block and contacts with the part of the wing in the stiff pile body, the wing expansion device will be stuck by the wing, at this time, the telescopic power source can be started to push the wing out of the outer wall of the stiff pile body, so that after the completion of the expansion of the upper layer of the wing, it can continue to be put down to the next layer of the wing, and the above steps are repeated to expand the next layer of the wing, so that all the wings can be pushed out of the outer wall of the stiff pile body through the hinge of the first rotating block and the second rotating block under the action of the telescopic power source, and the structure design is ingenious.

[0044] 7、The length of the transverse limiting rod is the same as the length of the diagonal line of the first through hole, when the wing expansion device is put into the stiff pile body, the two ends of the transverse limiting rod perpendicular to each other are in contact with the two side walls adjacent to the first through hole, so when the transverse limiting rod is put into the stiff pile body, the transverse limiting rod is put into horizontally in the state of being parallel to the diagonal line of the first through hole, so that the wing expansion device only moves in the axial direction of the stiff pile body when it is put into the prefabricated hollow stiff pile, and will not slide or rotate in the horizontal direction in the stiff pile body, so as to ensure the stability of the wing expansion device when working.

[0045] 8、When the wing expansion device is put into the stiff pile body, the two side walls of the vertical limiting rod are in contact with the two side walls adjacent to the first through hole, so when the vertical limiting rod is put into the stiff pile body, the two side walls of the vertical limiting rod are in contact with the two side walls adjacent to the first through hole, and the vertical limiting rod is fixedly installed at one end of the transverse limiting rod in the length direction, so that the wing expansion device only moves in the axial direction of the stiff pile body when it is put into the stiff pile body, and will not roll over in the direction of the diagonal line of the first through hole, so as to ensure the stability of the wing expansion device when working. BRIEF DESCRIPTION OF DRAWINGS

[0046] Figure 1 The three-dimensional structure schematic diagram of the wing expansion of the present application is shown;

[0047] Figure 2 The structure schematic diagram related to the second through hole and the mounting slot of the present application is shown;

[0048] Figure 3 The sectional view of the internal structure of the stiff pile body of the present application is shown;

[0049] Figure 4 The structure schematic diagram of the wing expansion device of the present application is shown;

[0050] Figure 5 The figure shows the size mark structure of the first through hole and the wing of the present application;

[0051] Figure 6 The figure shows the structure of the present application when the wing is expanded;

[0052] Figure 7 The figure shows the partial sectional view of the sliding block of the present application;

[0053] Figure 8 The figure shows the structure of the present application when the length of the connecting rope and the height of the inner hammer are shown;

[0054] Figure 9 The figure shows the structure of the present application when the distance between the upper end surface of the bullet head and the upper end surface of the sliding block is shown;

[0055] Figure 10 The figure shows the structure of the present application when the wing is not expanded;

[0056] Figure 11 The figure shows the structure of the present application when the wing is expanded.

[0057] In the figure: 101, the body of the reinforced pile; 102, the first through hole;

[0058] 201, the wing; 202, the second through hole;

[0059] 301, the mounting groove; 302, the first spring; 303, the limiting block; 304, the limiting groove;

[0060] 401, the first mounting frame; 402, the second mounting frame; 403, the telescopic power source; 404, the first rotating block; 405, the second rotating block;

[0061] 501, the horizontal limiting rod; 502, the vertical limiting rod;

[0062] 601, the bullet head; 602, the wing; 603, the steel bar;

[0063] 701, the mounting block; 702, the second spring; 703, the sliding block; 704, the inner hammer; 705, the connecting rope; 706, the hammer lifting block; 707, the third through hole; 708, the groove; 709, the fourth through hole. DETAILED DESCRIPTION

[0064] The embodiments of the present application are described below by specific examples, and those skilled in the art can easily understand other advantages and effects of the present application from the content disclosed in the specification.

[0065] Please refer to Figures 1 to 11It is to be understood that the structures, proportions, sizes, etc. shown in the drawings of the present disclosure are merely intended to facilitate the understanding of the present disclosure and are not intended to limit the scope of the present disclosure. Any modification, change or adjustment of the structures, proportions or sizes, as long as it does not affect the effects and purposes of the present disclosure, shall still fall within the scope of the present disclosure. Meanwhile, the terms such as "upper", "lower", "left", "right", "middle" and "one" in the present disclosure are merely intended to facilitate the understanding of the present disclosure and are not intended to limit the scope of the present disclosure. Any change or adjustment of the relative relationship, as long as it does not materially change the technical content, shall still be considered as the scope of the present disclosure.

[0066] The following embodiments are merely for illustration. The embodiments can be combined, and are not limited to the content shown in the following single embodiment.

[0067] Please refer to Figures 1 to 11 The present disclosure provides a prefabricated hollow core reinforced pile construction method with inner and outer wings, which comprises:

[0068] The hole is opened on the ground, and slurry is injected into the hole. After the hole is opened, the hole opening equipment is removed from the hole.

[0069] In the hole opening step, the diameter of the hole can be 700mm.

[0070] The pile placing step: temporarily fix the wing 201 in the state when the wing 201 is not unfolded by the iron sheet, that is, a part of the iron sheet is bonded to the outer side wall of the prefabricated hollow core reinforced pile, and the other part of the iron sheet is bonded to the wing 201, the bottom of the prefabricated hollow core reinforced pile is closed, and after the closure, the prefabricated hollow core reinforced pile is placed in the hole, the slurry wraps the prefabricated hollow core reinforced pile outside, and the hollow inside of the prefabricated hollow core reinforced pile is still dry.

[0071] In the pile placing step, the cross section of the prefabricated hollow core reinforced pile can be a square with a side length of 400mm, and the center axis of the prefabricated hollow core reinforced pile placed in the hole coincides with the center axis of the hole.

[0072] The extension step is that the wing expansion device is lowered to the uppermost wing 201 in the prefabricated hollow core steel pile, the uppermost wing 201 blocks the wing expansion device from continuing to be lowered, at this time, the wing expansion device is started, the wing expansion device pushes the temporarily fixed iron sheet away and continues to push the wing 201 out of the outer wall of the prefabricated hollow core steel pile, the part of the wing 201 pushed out of the prefabricated hollow core steel pile is wrapped by the slurry, then the wing expansion device continues to be lowered, and the above steps are repeated to push the wings 201 out of the outer wall of the prefabricated hollow core steel pile from top to bottom, and the wing expansion device is taken out of the prefabricated hollow core steel pile after all the wings 201 are pushed out.

[0073] Please refer to Figures 1 to 3 In the pile lowering step, the prefabricated hollow core steel pile comprises:

[0074] The steel pile body 101, the upper and lower end faces of the steel pile body 101 are penetrated by the first through hole 102;

[0075] A plurality of expansion units, a plurality of the expansion units are arranged in the axial direction of the steel pile body 101, each of the expansion units comprises a plurality of expansion modules, a plurality of the expansion modules are circularly arranged along the center line of the steel pile body 101, each of the expansion modules comprises a wing 201 and a second through hole 202, the second through hole 202 is arranged on the steel pile body 101, the second through hole 202 penetrates the inner and outer walls of the steel pile body 101, the wing 201 is in the shape of a sector, the wing 201 is rotationally installed in the second through hole 202, the rotation axis of the wing 201 is perpendicular to the center line of the steel pile body 101, and the rotation axis of the wing 201 is located in the second through hole 202;

[0076] When the wing 201 is not unfolded, part of the wing 201 is located in the steel pile body 101;

[0077] During the process of rotating the wing 201 to the unfolded state, the wing 201 continuously closes the second through hole 202, and part of the wing 201 is located outside the steel pile body 101.

[0078] In the embodiment, when the prefabricated hollow core stiff pile is used for construction, the wing 201 can be temporarily fixed in the state of not being unfolded by the iron sheet, specifically, a part of the iron sheet is bonded to the outer side wall of the stiff pile body 101, and another part of the iron sheet is bonded to the wing 201. When the iron sheet temporarily fixes the wing 201 in the state of not being unfolded, the wing 201 and the second through hole 202 are flush with the side wall outside the stiff pile body 101, at this time, the wing 201 completely fills the second through hole 202. Since the shape of the wing 201 is fan-shaped, the wing 201 is inclined to extend into the first through hole 102. In the above manner, all the wings 201 of the stiff pile body 101 from top to bottom are temporarily fixed in the state of not being unfolded. Then, the stiff pile body 101 with the fixed wings 201 and the closed bottom is placed in the hole. After the wing 201 rotates to the unfolded state, the wing 201 still completely fills the second through hole 202, and part of the wing 201 is located outside the stiff pile body 101.

[0079] The wings 201 of the present application are arranged in the axial direction of the stiff pile body 101. When the stiff pile body 101 with the fixed wings 201 and the closed bottom is placed in the hole, the wings 201 are installed by rotating from top to bottom. In subsequent construction, the stiff pile body 101 can rotate to the unfolded state through the wings 201 from top to bottom to improve the bearing capacity of the stiff pile body 101. The wings 201 completely fill the second through hole 202 before and after unfolding. The wings 201 support the stiff pile body 101 in the axial direction by closing the second through hole 202, so as to ensure that the axial bearing capacity of the stiff pile body 101 will not be weakened after the wings 201 rotate to the unfolded state. The structure is cleverly designed, and the stiff pile body 101 after construction has good stability.

[0080] Please refer to Figure 2 and Figure 3 The upper end surface of the wing 201 is arc-shaped, and the central axis of the upper end surface of the wing 201 coincides with the rotation axis of the wing 201.

[0081] The upper end surface of the second through hole 202 is fitted with the upper end surface of the wing 201.

[0082] In the embodiment, after the stiff pile body 101 with the temporarily fixed wings 201 and the closed bottom is placed in the hole by the iron sheet, the hole is injected with slurry, so that the slurry wraps the stiff pile body 101 on the outside. Then, during the process of rotating the wing 201 from the unfolded state to the unfolded state, the wing 201 rotates along the rotation axis of the wing 201.

[0083] In the process that the wing 201 rotates from the unexpanded state to the expanded state, the upper end surface of the second through hole 202 is always attached to the upper end surface of the wing 201, so that the upper end surface of the second through hole 202 is closed by the wing 201 in the process that the wing 201 expands, and the slurry cannot flow into the rigid pile body 101 from the upper end surface of the second through hole 202.

[0084] Please refer to Figure 2 and Figure 3 , the expansion module further comprises a mounting groove 301, a first spring 302, a limiting block 303 and a limiting groove 304;

[0085] The mounting groove 301 is arranged on the lower end surface of the second through hole 202, one end of the first spring 302 is fixedly connected to the lower end of the mounting groove 301, and the other end of the first spring 302 is fixedly connected to the limiting block 303; the extension direction of the first spring 302 is consistent with the axial direction of the mounting groove 301;

[0086] The rotation axis of the wing 201 is located at the upper part of the second through hole 202, and the limiting groove 304 is arranged on the lower end surface of the wing 201; when the wing 201 rotates to the expanded state in the second through hole 202, the limiting block 303 extends into the limiting groove 304 under the action of the first spring 302.

[0087] In this embodiment, after the rigid pile body 101 with the temporarily fixed wing 201 and the closed bottom is placed in the hole, the lower end surface of the wing 201 extrudes the limiting block 303 into the mounting groove 301, the limiting block 303 compresses the first spring 302 to the compressed state, the slurry is injected into the hole, and after the slurry wraps the rigid pile body 101 on the outside, when the wing 201 rotates from the unexpanded state to the expanded state, the limiting groove 304 rotates to the axial direction consistent with the extension direction of the first spring 302, the first spring 302 extends from the compressed state to the natural state, and the limiting block 303 extends into the limiting groove 304 to be locked when extending from the compressed state to the natural state, that is, the wing 201 is in the expanded state at this time.

[0088] In the process that the wing 201 rotates from the unexpanded state to the expanded state, the limiting block 303 is extended into the limiting groove 304 by the first spring 302 reset from the compressed state to the natural state, so that the wing 201 can automatically maintain the expanded state after rotating to the expanded state, and will not be extruded back to the unexpanded state by the slurry wrapped on the outside of the rigid pile body 101, and the structure design is ingenious.

[0089] Please refer to Figure 2 and Figure 3 , the lower end surface of the second through hole 202 is an arc surface;

[0090] The lower end surface of the second through hole 202 is in abutment with the lower end surface of the wing 201.

[0091] In this embodiment, after the wing 201 is temporarily fixed by the iron sheet and the bottom of the stiff pile body 101 is closed, the slurry is injected into the hole so that the slurry wraps the stiff pile body 101 on the outside, and then the lower end surface of the wing 201 is in abutment with the lower end surface of the second through hole 202 during the process of rotating the wing 201 from the unfolded state to the unfolded state.

[0092] During the process of rotating the wing 201 from the unfolded state to the unfolded state, the lower end surface of the second through hole 202 is always in abutment with the lower end surface of the wing 201, so that the lower end surface of the second through hole 202 is closed by the wing 201 during the unfolding process of the wing 201, and the slurry cannot flow into the stiff pile body 101 from the lower end surface of the second through hole 202.

[0093] Please refer to Figure 3 and Figure 5 , the maximum distance value z of the wing 201 extending into the first through hole 102 when the wing 201 is unfolded;

[0094] The cross section of the first through hole 102 is a square, and one end surface of the wing 201 is in abutment with one side wall of the square first through hole 102;

[0095] The side wall of the square first through hole 102 in abutment with the wing 201 is the first side wall, and the side wall of the square first through hole 102 parallel to the first side wall is the second side wall;

[0096] The distance between the other end surface of the wing 201 and the second side wall is greater than or equal to z.

[0097] In this embodiment, since one end surface of the wing 201 is in abutment with the first side wall, when the distance between the other end surface of the wing 201 and the second side wall is equal to z, the area of the wing 201 located in the outer partial region of the stiff pile body 101 is the largest during the process of rotating the wing 201 from the unfolded state to the unfolded state, and the distance between the other end surface of the wing 201 and the second side wall is selected as z in this embodiment.

[0098] As the distance between the other end surface of the wing 201 and the second side wall is greater than z and gradually increases, the area of the wing 201 located in the outer partial region of the stiff pile body 101 gradually decreases during the process of rotating the wing 201 from the unfolded state to the unfolded state.

[0099] The present application can control the distance between the other end face of the wing 201 and the second side wall to adjust the area of the wing 201 located in the outer partial area of the stiff pile body 101 when the wing 201 rotates from the non-expanded state to the expanded state, and the area is the largest when the distance between the other end face of the wing 201 and the second side wall is equal to z, that is, the area of the wing 201 located in the outer partial area of the stiff pile body 101 is the largest, and at this time, the carrying capacity of the wing 201 is the best, thereby the stability of the stiff pile body 101 can be strengthened to the maximum extent.

[0100] Please refer to Figure 1 , in the lower pile step, the bottom of the prefabricated hollow core stiff pile is sealed before the prefabricated hollow core stiff pile is placed in the hole;

[0101] Here, the way of sealing the bottom of the prefabricated hollow core stiff pile can be welding a steel plate on the bottom of the prefabricated hollow core stiff pile to seal.

[0102] In this embodiment, after the wing 201 is temporarily fixed by the iron sheet and the bottom of the stiff pile body 101 is sealed by the steel plate, the stiff pile body 101 is placed in the hole, and since the lower end face of the stiff pile body 101 is sealed by the steel plate, the slurry in the hole wraps the stiff pile body 101 on the outside.

[0103] The present application is placed in the hole after the lower end face of the stiff pile body 101 is sealed, so that the first through hole 102 of the stiff pile body 101 is still dry after the stiff pile body 101 is placed in the hole, thereby the wing expansion device can be smoothly lowered into the stiff pile body 101 to perform subsequent construction steps.

[0104] Please refer to Figure 1 , Figure 3 and Figure 4 , in the expansion step, the wing expansion device comprises a first mounting frame 401, a second mounting frame 402, a telescopic power source 403 and a plurality of articulated modules;

[0105] Here, the telescopic power source 403 is not limited, and its function is to provide telescopic power, which can be a cylinder, a hydraulic cylinder, etc.

[0106] The fixed end of the telescopic power source 403 is fixedly installed on the first mounting frame 401, and the extension end of the telescopic power source 403 is fixedly installed on the second mounting frame 402, and the first mounting frame 401 is located above the second mounting frame 402;

[0107] When the wing expansion device is placed in the stiff pile body 101, the axial direction of the telescopic power source 403 coincides with the center line of the stiff pile body 101;

[0108] The number of articulated modules is the same as the number of expansion modules of each expansion unit;

[0109] A plurality of the articulated modules are circularly arrayed along the axial direction of the telescopic power source 403, each of the articulated modules comprises a first rotating block 404 and a second rotating block 405, one end of the first rotating block 404 is hingedly connected with the first mounting frame 401, the other end of the first rotating block 404 is hingedly connected with one end of the second rotating block 405, the other end of the second rotating block 405 is hingedly connected with the second mounting frame 402, the first rotating block 404 and the second rotating block 405 push the outrigger 201 towards the outer wall of the stiff pile body 101 under the action of the telescopic power source 403.

[0110] In this embodiment, after the stiff pile body 101 with the temporarily fixed outriggers 201 and the closed bottom is placed in the hole, the slurry is injected into the hole, the slurry is injected from the outside of the stiff pile body 101, so that the slurry wraps the stiff pile body 101 on the outside, then the outrigger expanding device is lowered from the stiff pile body 101 to the uppermost outrigger 201, the uppermost outrigger 201 blocks the outrigger expanding device from continuing to lower, at this time the telescopic power source 403 is started, the telescopic power source 403 retracts to make the first rotating block 404 and the second rotating block 405 relatively rotate, at this time the hinged part of the first rotating block 404 and the second rotating block 405 pushes the outrigger 201 to push away the temporarily fixed iron sheet and then continues to push the outrigger 201 outwards to the outer wall of the stiff pile body 101, after the limiting block 303 extends into the limiting groove 304 under the action of the first spring 302, the telescopic power source 403 extends to the initial position, then the outrigger expanding device continues to lower, and the above steps are repeated to sequentially push the outrigger 201 outwards to the outer wall of the stiff pile body 101 through the hinged part of the first rotating block 404 and the second rotating block 405 from top to bottom.

[0111] In this invention, after the rigid pile body 101, with its bottom closed and temporarily fixed by iron sheets, is placed in the hole, a portion of the support wing 201 is located inside the rigid pile body 101. When the support wing extension device is lowered from inside the rigid pile body 101 to the hinge point between the first rotating block 404 and the second rotating block 405, and contacts the portion of the support wing 201 located inside the rigid pile body 101, the support wing extension device will be stuck by the support wing 201. At this time, the telescopic power source 403 can be activated to push the support wing 201 toward the outer wall of the rigid pile body 101, until the limiting block 303 is reached by the first spring 30. After the extension wing 201 is inserted into the limiting groove 304 under the action of 2, it is automatically fixed in the unfolded state. This means that the extension device does not need to keep the extension wing 201 in the unfolded state. After the upper layer of extension wing 201 is unfolded, it can continue to be lowered to the next layer of extension wing 201. The above steps are repeated to unfold the next layer of extension wing 201. Thus, all extension wing 201 can be pushed out of the outer wall of the rigid pile body 101 through the hinge of the first rotating block 404 and the second rotating block 405 under the action of the telescopic power source 403. The structure is ingeniously designed.

[0112] Please see Figure 3 and Figure 4 The wing extension device also includes a lateral limiting rod 501;

[0113] The lateral limiting rod 501 is fixedly installed on the upper end face of the first mounting bracket 401. The length direction of the lateral limiting rod 501 is perpendicular to the axial direction of the telescopic power source 403. The length of the lateral limiting rod 501 is the same as the length of the diagonal of the first through hole 102.

[0114] When the support wing extension device is placed inside the stiff pile body 101, both ends of the transverse limiting rod 501 in the length direction have mutually perpendicular surfaces, and the mutually perpendicular surfaces at both ends of the transverse limiting rod 501 in the length direction are in contact with the two adjacent side walls of the first through hole 102.

[0115] In this embodiment, when the wing extension device is placed into the stiff pile body 101, the two perpendicular surfaces of the transverse limiting rod 501 in the length direction are kept in contact with the two adjacent side walls of the first through hole 102 and extend into the stiff pile body 101 from top to bottom.

[0116] The length of the transverse limiting rod 501 is the same as the length of the diagonal line of the first through hole 102, and when the wing expansion device is placed in the rigid pile body 101, the faces of the two ends of the transverse limiting rod 501 perpendicular to each other in the length direction are attached to the two side walls adjacent to the first through hole 102, so that when the wing expansion device is placed in the rigid pile body 101, the transverse limiting rod 501 is placed in the rigid pile body 101 by being placed horizontally downward in a state of being parallel to the diagonal line of the first through hole 102, so that the wing expansion device only moves in the axial direction of the rigid pile body 101 when it is placed in the rigid pile body 101, and does not slide or rotate in the horizontal direction in the rigid pile body 101, thereby ensuring the stability of the wing expansion device when it works.

[0117] Please refer to Figures 3 to 5 , the wing expansion device further comprises a vertical limiting rod 502;

[0118] The length of the vertical limiting rod 502 is L, and the length of the side of the cross section of the first through hole 102 is a;

[0119] L≥2a;

[0120] The lower end of the vertical limiting rod 502 is fixedly installed at one end of the transverse limiting rod 501 in the length direction, and the length direction of the vertical limiting rod 502 is perpendicular to the length direction of the transverse limiting rod 501;

[0121] When the wing expansion device is placed in the rigid pile body 101, the two side walls of the vertical limiting rod 502 are attached to the two side walls adjacent to the first through hole 102.

[0122] In this embodiment, when the wing expansion device is placed in the rigid pile body 101, the faces of the two ends of the transverse limiting rod 501 perpendicular to each other in the length direction remain attached to the two side walls adjacent to the first through hole 102 and extend into the rigid pile body 101 from top to bottom, and the two side walls of the vertical limiting rod 502 remain attached to the two side walls adjacent to the first through hole 102 and extend into the rigid pile body 101 from top to bottom;

[0123] The lowering mode of the wing expansion device is not limited here. When the upper end surface of the vertical limiting rod 502 is higher than the upper end surface of the pile body 101 when the lowest wing 201 in the pile body 101 is pushed out by the wing expansion device towards the outer wall of the pile body 101, the wing expansion device can be lowered by continuously lowering the vertical limiting rod 502. When the upper end surface of the vertical limiting rod 502 is lower than the upper end surface of the pile body 101 when the lowest wing 201 in the pile body 101 is pushed out by the wing expansion device towards the outer wall of the pile body 101, the vertical limiting rod 502 can be set to be spliced. Here, the bottom end surface of the vertical limiting rod 502 above can be provided with a stud, and the top end surface of the vertical limiting rod 502 below can be provided with a threaded hole. The stud and the threaded hole are threadedly connected, thereby realizing the splicing of the upper and lower vertical limiting rods 502. The uppermost vertical limiting rod 502 is higher than the upper end surface of the pile body 101 by splicing a plurality of vertical limiting rods 502 upwards. When the wing expansion device is working, the vertical limiting rod 502 protruding from the upper end surface of the pile body 101 is manually fixed to ensure that the wing expansion device does not move upwards when working.

[0124] When the wing expansion device is placed in the pile body 101, the two side walls of the vertical limiting rod 502 adjacent to the two side walls of the first through hole 102 are fitted. When the vertical limiting rod 502 is lowered into the pile body 101, the vertical limiting rod 502 is kept in a state of fitting the two side walls adjacent to the two side walls of the first through hole 102 from top to bottom, and the vertical limiting rod 502 is fixedly installed at one end of the length direction of the horizontal limiting rod 501, so that the wing expansion device only moves in the axial direction of the pile body 101 when it is lowered into the pile body 101, and does not roll over in the diagonal direction of the first through hole 102, thereby ensuring the stability of the wing expansion device when working.

[0125] Please refer to Figure 6 , Figure 10 and Figure 11 , as another embodiment of the present application, when the lower end surface of the pile body 101 is closed, the impact bullet head 601 is filled into the bottom of the first through hole 102, the side wall of the impact bullet head 601 is sealed with the inner wall of the first through hole 102 by a sealing ring, and the lower end surface of the pile body 101 is not closed by a steel plate.

[0126] The bottom expansion unit is arranged on the lower end surface of the prestressed pile body 101, and comprises a plurality of expansion wings 602 arranged in a circular array along the center line of the prestressed pile body 101. Each expansion wing 602 is in the shape of a triangular prism and is hinged to the lower end surface of the prestressed pile body 101. The rotation axis of the hinge of each expansion wing 602 is perpendicular to the center line of the prestressed pile body 101.

[0127] When the expansion wings 602 are not expanded, the plurality of expansion wings 602 close the lower end surface of the first through hole 102.

[0128] When the expansion wings 602 are not expanded, the plurality of expansion wings 602 do not completely close the lower end surface of the first through hole 102.

[0129] During the rotation of the expansion wings 602 to the expanded state, the expansion wings 602 open the lower end surface of the first through hole 102, and the expansion wings 602 form a bottom expansion at the bottom end of the prestressed pile body 101.

[0130] During the pile driving step, the bottom expansion unit can be temporarily fixed in the unexpanded state by embedding steel bars 603 on each expansion wing 602 and then binding all the steel bars 603 together with wire.

[0131] After the expansion step is completed, the impact bullet head 601 at the bottom of the first through hole 102 is repeatedly hammered using the hammering limiting device, so that the impact bullet head 601 pushes the expansion wings 602 at the bottom of the prestressed pile body 101 to expand the wire and then continues to expand the expansion wings 602 towards the outer wall of the prefabricated hollow prestressed pile.

[0132] In this embodiment, when a prefabricated hollow prestressed pile is used for construction, the bottom of the prestressed pile body 101 can be first filled with the impact bullet head 601 from the bottom end of the prestressed pile body 101 upwards to the bottom of the first through hole 102, so that the impact bullet head 601 closes the bottom of the first through hole 102. Then, by embedding steel bars 603 on each expansion wing 602 and binding all the steel bars 603 together with wire, the plurality of expansion wings 602 are temporarily fixed in the unexpanded state. A hole is drilled in the ground and grout is injected into the hole. Then, the prestressed pile body 101 with the temporarily fixed expansion wings 602 and support wings 201 is placed in the hole. After the support wings 201 are pushed out to the expanded state by the support wing expansion device, the expansion wings 602 open the bottom of the first through hole 102 under the repeated hammering of the hammering limiting device, and the expansion wings 602 expand towards the outer wall of the prestressed pile body 101.

[0133] The stretch wing 602 of the present application is circularly arranged along the center line of the stiff pile body 101, and when the stretch wing 602 is expanded, the stretch wing 602 is rotated to an unfolded state to improve the pile end resistance of the stiff pile body 101 after the stiff pile body 101 with the temporarily fixed stretch wing 602 is placed in the hole, the structure design is simple, the manufacturing cost is low, and the stability of the stiff pile body 101 after construction is good.

[0134] Please refer to Figure 10 and Figure 11 , the side wall of the stretch wing 602 comprises a first side wall, a second side wall and a third side wall;

[0135] The number of the stretch wing 602 can be four, the third side wall of the stretch wing 602 is flush with the corresponding outer side wall of the stiff pile body 101 when the stretch wing 602 is not unfolded, the first side wall of one of the stretch wing 602 is attached to the second side wall of the adjacent one of the stretch wing 602, and the second side wall of one of the stretch wing 602 is attached to the first side wall of the adjacent one of the stretch wing 602.

[0136] In this embodiment, when the stretch wing 602 closes the lower end surface of the first through hole 102, the first side wall of one of the stretch wing 602 is attached to the second side wall of the adjacent one of the stretch wing 602, and the second side wall of one of the stretch wing 602 is attached to the first side wall of the adjacent one of the stretch wing 602, so that the side wall between the adjacent two of the four stretch wing 602 is attached, so as to temporarily fix the four stretch wing 602 in the unfolded state.

[0137] Please refer to Figure 10 and Figure 11 , the intersection of the first side wall and the second side wall of the stretch wing 602 is embedded with a steel bar 603, the upper end surface of the steel bar 603 is flush with the upper end surface of the stretch wing 602, and the lower end surface of the steel bar 603 protrudes from the lower end surface of the stretch wing 602.

[0138] In this embodiment, when all the stretch wing 602 is rotated to the unfolded state, all the steel bars 603 are tied together by wire, so as to temporarily fix the several stretch wing 602 in the unfolded state.

[0139] The present application temporarily fixes all the stretch wing 602 in the unfolded state by tying the several steel bars 603 together by wire when closing the lower end surface of the first through hole 102, so as to ensure that the subsequent stretch wing 602 will not be opened to open the lower end surface of the first through hole 102 when the stretch wing 602 is placed in the hole with the stiff pile body 101, and the structure design is ingenious.

[0140] Please refer to Figure 10 , when the stretch wing 602 is not unfolded, the rotation axis of the stretch wing 602 hinge is the same height as the upper end surface of the stretch wing 602.

[0141] In this embodiment, when the stretch wing 602 rotates along the rotation axis of the stretch wing 602 hinge, the upper end surface of the stretch wing 602 always remains not higher than the posture rotation of the rotation axis of the stretch wing 602 hinge.

[0142] Please refer to Figure 6 and Figure 10 , in the bottom expanding step, the side wall of the impact bullet head 601 is sealed with the inner side wall of the stiff pile body 101 through a sealing ring, the head of the impact bullet head 601 is conical, and the head of the impact bullet head 601 is located at the lower end of the impact bullet head 601.

[0143] In this embodiment, first, all the stretch wings 602 are rotated to the unfolded state, then the impact bullet head 601 is stuffed upwards from the bottom end of the stiff pile body 101 to the bottom of the first through hole 102, when stuffing, the side wall of the impact bullet head 601 is sealed with the side wall inside the first through hole 102 through a sealing ring, the head of the impact bullet head 601 is located at the lower end of the impact bullet head 601, then all the stretch wings 602 are rotated to the unfolded state, then all the steels 603 are tied together through iron wire to temporarily fix all the stretch wings 602 to the unfolded state, and wait for subsequent operation.

[0144] The impact bullet head 601 is stuffed in the present application, the head of the impact bullet head 601 is located at the lower end of the impact bullet head 601, the head of the impact bullet head 601 is conical, so that when the inner hammer 704 hammers the impact bullet head 601, the impact bullet head 601 is in contact with the stretch wing 602 when the stretch wing 602 is unfolded, that is, the force point of the stretch wing 602 is far away from the rotation axis of the stretch wing 602, so that the impact bullet head 601 can smoothly push the stretch wing 602 to rotate with smaller force when the stretch wing 602 is pushed to rotate, and the structure design is ingenious.

[0145] Please refer to Figure 2 , Figure 6 , Figure 7 and Figure 8 , in the bottom expanding step, the hammering limiting device comprises a mounting block 701, a spring, a sliding block 703, an inner hammer 704, a connecting rope 705 and a hammer lifting block 706.

[0146] The mounting block 701 is fixedly installed on the upper end surface of the stiff pile body 101, second through holes 202 are formed through the upper and lower end surfaces of the mounting block 701, the cross section of the second through holes 202 is the same as that of the first through holes 102, and the second through holes 202 are communicated with the first through holes 102;

[0147] Here, the way in which the mounting block 701 is installed on the upper end surface of the stiff pile body 101 is not limited, and can be welding or bolt connection;

[0148] A plurality of springs are arranged on the mounting block 701 along the center line circle of the stiff pile body 101, the lower end surfaces of the plurality of springs are fixedly connected with the upper end surface of the mounting block 701, a recess 708 is formed in the lower end surface of the sliding block 703, the upper end surfaces of the plurality of springs are fixedly connected with the upper end surface of the recess 708, the mounting block 701 is located in the recess 708, and the sliding direction of the sliding block 703 is consistent with the extension direction of the springs;

[0149] Third through holes 707 are formed through the upper and lower end surfaces of the sliding block 703, the cross section of the third through holes 707 is the same as that of the second through holes 202, and the third through holes 707 are communicated with the second through holes 202;

[0150] One end of the connecting rope 705 is fixedly connected with the upper end surface of the inner hammer 704, the other end of the connecting rope 705 is fixedly connected with the lower end surface of the hammer lifting block 706, and when the inner hammer 704 strikes the bullet head 601 in the stiff pile body 101, the hammer lifting block 706 contacts and presses the upper end surface of the sliding block 703.

[0151] In this embodiment, first, all the stretch wings 602 are rotated to the unfolded state, then the impact bullet head 601 is filled from the bottom end of the stiff pile body 101 to the bottom of the first through hole 102, the side wall of the impact bullet head 601 is closed with the side wall inside the first through hole 102 through the sealing ring, the head of the impact bullet head 601 is located at the lower end of the impact bullet head 601, then all the steel bars 603 are tied together by the iron wire to temporarily fix all the stretch wings 602 to the unfolded state, the wing 201 is temporarily fixed in the state of unfolding through the iron sheet, that is, a part of the iron sheet is bonded on the outer side wall of the prefabricated hollow core stiff pile, and the other part of the iron sheet is bonded on the wing 201, then a hole is opened on the ground, and the slurry is injected into the hole, then the stiff pile body 101 with the temporarily fixed wing 201 and stretch wing 602 is placed in the hole, after all the wings 201 are pushed out to the outer wall of the stiff pile body 101 from top to bottom through the wing expansion device, the wing expansion device is removed, and then the inner hammer 704 is driven into the fourth through hole 709, the third through hole 707 and the first through hole 102 in sequence through the lifting hammer block 706 to repeatedly hammer the impact bullet head 601, the stretch wing 602 is opened by the iron wire, and then the stretch wing 602 is unfolded to the outer wall of the stiff pile body 101 to form an expanded bottom, after the hammering is completed, the inner hammer 704 is removed, and the impact bullet head 601 is left between the stretch wings 602 to block the stretch wings 602 and prevent them from rotating back.

[0152] The inner hammer 704 of the present application is left in the first through hole 102 after hammering the impact bullet head 601, the stretch wing 602 is opened by the impact bullet head 601, and the side wall of the impact bullet head 601 is still closed with the side wall inside the first through hole 102, so that the slurry cannot flow into the first through hole 102 from the bottom of the stiff pile body 101, and the impact bullet head 601 can keep the stretch wing 602 in the unfolded state to form an expanded bottom, and the stretch wing 602 cannot rotate back to the unfolded state, which is a clever structure design.

[0153] Please refer to Figure 2 and Figure 7 , the cross section of the inner hammer 704 is smaller than the cross section of the first through hole 102.

[0154] In this embodiment, when the inner hammer 704 repeatedly hammers the impact bullet head 601 through the lifting hammer block 706, the cross section of the inner hammer 704 is smaller than the cross section of the first through hole 102, so the inner hammer 704 can freely fall to hammer the impact bullet head 601.

[0155] When the inner hammer 704 hammers the impact bullet head 601, the inner hammer 704 can freely fall to hammer the impact bullet head 601, so as to ensure that the impact bullet head 601 is hammered to the state of the stretched wing 602 being unfolded by the inner hammer 704.

[0156] Please refer to Figure 6 When the lifting hammer block 706 is in contact with the sliding block 703, the outer side wall of the lifting hammer block 706 is flush with the outer side wall of the sliding block 703.

[0157] In this embodiment, when the inner hammer 704 is repeatedly hammered against the impact bullet head 601 by the lifting hammer block 706, the lifting hammer block 706 is blocked by the upper end surface of the sliding block 703 when it is put down to the upper end surface of the sliding block 703, so that the lifting hammer block 706 is in contact with the sliding block 703.

[0158] When the lifting hammer block 706 is put down to the upper end surface of the sliding block 703, the outer side wall of the lifting hammer block 706 is put down to be flush with the outer side wall of the sliding block 703, so that the sliding block 703 can support the lifting hammer block 706 from continuing to fall into the first through hole 102, thereby ensuring that the lifting hammer block 706 can be repeatedly lifted and put down to hammer the impact bullet head 601 by the inner hammer 704 driven by the connecting rope 705.

[0159] Please refer to Figure 6 , Figure 7 , Figure 8 , Figure 9 and Figure 11 When the inner hammer 704 hammers the stretched wing 602 to the unfolded state, the upper end surface of the groove 708 is in contact with the upper end surface of the mounting block 701, the lower end surface of the sliding block 703 is flush with the lower end surface of the mounting block 701, the distance from the upper end surface of the impact bullet head 601 to the upper end surface of the sliding block 703 is a, the length of the connecting rope 705 is b, the height of the inner hammer 704 is c, and a=b+c.

[0160] In this embodiment, a hole is opened on the ground, and a slurry is injected into the hole, and the impact bullet head 601 is filled upward from the bottom end of the stiff pile body 101 to the bottom of the first through hole 102, and then the stiff pile body 101 with the temporary closed branch wings 201 and the stretching wings 602 is placed into the hole, and then all the branch wings 201 are pushed outwards to the outer wall of the stiff pile body 101 from top to bottom through the branch wing expansion device, and then the branch wing expansion device is taken out, and then the inner hammer 704 is driven by the lifting hammer block 706 to repeatedly hammer the impact bullet head 601, and before the inner hammer 704 hammers the stretching wings 602 to the unfolded state, the impact bullet head 601 does not drop to the specified position, and the connecting rope 705 is not completely straightened when the lower end surface of the inner hammer 704 contacts the upper end surface of the impact bullet head 601, at this time, the lower end surface of the sliding block 703 is higher than the lower end surface of the mounting block 701, and when the inner hammer 704 repeatedly hammers the stretching wings 602 through the impact bullet head 601 until it is observed that the lower end surface of the sliding block 703 is flush with the lower end surface of the mounting block 701, that is, at this time, the impact bullet head 601 drops to the specified position, and the connecting rope 705 is just completely straightened, and the second spring 702 is compressed to the lower end surface of the sliding block 703 being flush with the lower end surface of the mounting block 701 under the combined gravity of the lifting hammer block 706, the connecting rope 705 and the inner hammer 704, which indicates that the inner hammer 704 has hammered the stretching wings 602 to the unfolded state, at this time, the impact bullet head 601 is clamped between the stretching wings 602, and seals the lower end surface of the first through hole 102, and when it is observed that the lower end surface of the sliding block 703 is flush with the lower end surface of the mounting block 701, the connecting rope 705 and the inner hammer 704 are lifted out of the stiff pile body 101 through the lifting of the lifting hammer block 706, so as to complete the expansion work of the stretching wings 602.

[0161] Before the impact bullet head 601 props open the stretching wings 602 to the unfolded state, the connecting rope 705 is not completely straightened when the lower end surface of the inner hammer 704 contacts the upper end surface of the impact bullet head 601, at this time, the force acting on the second spring 702 is the gravity of the lifting hammer block 706 and the connecting rope 705, and the lower end surface of the sliding block 703 is higher than the lower end surface of the mounting block 701 under the support of the second spring 702, when the inner hammer 704 hammers the impact bullet head 601 to prop open the stretching wings 602 to the unfolded state, the connecting rope 705 is just completely straightened in the first through hole 102, and the second spring 702 is compressed to the lower end surface of the sliding block 703 being flush with the lower end surface of the mounting block 701 under the combined gravity of the lifting hammer block 706, the connecting rope 705 and the inner hammer 704, so that whether the stretching wings 602 are hammered to the unfolded state can be judged by observing whether the lower end surface of the sliding block 703 is flush with the lower end surface of the mounting block 701 in the process of the inner hammer 704 hammering the impact bullet head 601, and the structure is cleverly matched.

[0162] The above embodiments are only illustrative of the principles of the present application and its efficacy, and are not intended to limit the present application. Any modification or change made by any person skilled in the art without departing from the spirit and scope of the present application shall be covered by the claims of the present application.

Claims

1. A construction method for precast hollow reinforced piles with inward and outward wing extensions, characterized in that: The construction method for the precast hollow core reinforced piles includes: Hole-forming steps: Drill holes in the ground and inject slurry into the holes; Piling steps: Place the precast hollow rigid pile in the hole, wrap the precast hollow rigid pile with grout on the outside, and keep the hollow part of the precast hollow rigid pile dry. Extension steps: Lower the wing extension device from inside the precast hollow rigid pile to the uppermost wing. The uppermost wing will block the wing extension device from being lowered further. At this time, activate the wing extension device. The wing extension device will push the wing out toward the outer wall of the precast hollow rigid pile. Then, the wing extension device will continue to be lowered. Repeat the above steps to push the wing out toward the outer wall of the precast hollow rigid pile from top to bottom. The pile driving step includes the following precast hollow reinforced piles: The rigid pile body has a first through hole penetrating its upper and lower end faces; A plurality of extension units are arranged in an array along the axial direction of the stiffened pile body. Each extension unit includes a plurality of extension modules. The plurality of extension modules are arranged in a circular array along the center line of the stiffened pile body. Each extension module includes a support wing and a second through hole. The second through hole is opened on the stiffened pile body and penetrates the inner and outer walls of the stiffened pile body. The support wing is fan-shaped and is rotatably installed in the second through hole. The rotation axis of the support wing is perpendicular to the center line of the stiffened pile body and the rotation axis of the support wing is located in the second through hole. When the support wing is not deployed, a portion of the support wing is located within the body of the rigid pile. During the process of the support wing rotating to the deployed state, the support wing continuously closes the second through hole, and a part of the support wing is located outside the stiff pile body; When the support wing is not deployed, the maximum distance the support wing extends into the first through hole is z; The cross-section of the first through hole is square, and one end face of the support wing is in contact with one side wall of the square first through hole; The sidewall of the first through hole of the square that fits with the support wing is the first sidewall, and the sidewall of the first through hole of the square that is parallel to the first sidewall is the second sidewall. The distance between the other end face of the support wing and the second sidewall is greater than or equal to z; In the expansion step, the wing expansion device includes a first mounting frame, a second mounting frame, a telescopic power source, and several hinge modules; The fixed end of the telescopic power source is fixedly installed on the first mounting bracket, and the extended end of the telescopic power source is fixedly installed on the second mounting bracket. The first mounting bracket is located above the second mounting bracket. When the extension device is inserted into the rigid pile body, the axial direction of the telescopic power source coincides with the center line of the rigid pile body. A plurality of the hinge modules are arranged in a circular array along the axial direction of the telescopic power source. Each hinge module includes a first rotating block and a second rotating block. One end of the first rotating block is hinged to a first mounting frame, the other end of the first rotating block is hinged to one end of the second rotating block, and the other end of the second rotating block is hinged to a second mounting frame. Under the action of the telescopic power source, the first rotating block and the second rotating block push the support wing out toward the outer wall of the rigid pile body. The wing extension device also includes a lateral limiting rod; The lateral limiting rod is fixedly installed on the upper end face of the first mounting bracket. The length direction of the lateral limiting rod is perpendicular to the axial direction of the telescopic power source, and the length of the lateral limiting rod is the same as the length of the diagonal of the first through hole. When the wing extension device is placed into the rigid pile body, both ends of the transverse limiting rod in the length direction have mutually perpendicular surfaces, and the mutually perpendicular surfaces of the two ends of the transverse limiting rod in the length direction are in contact with the two side walls corresponding to the first through hole.

2. The construction method for a precast hollow reinforced pile with inward and outward wings according to claim 1, characterized in that: The upper end face of the support wing is arc-shaped, and the central axis of the upper end face of the support wing coincides with the rotation axis of the support wing; The upper end face of the second through hole is in contact with the upper end face of the support wing.

3. The construction method for a precast hollow reinforced pile with inward and outward winging as described in claim 2, characterized in that: The expansion module also includes a mounting slot, a first spring, a limiting block, and a limiting slot; The mounting groove is formed on the lower end face of the second through hole. One end of the first spring is fixedly connected to the lower end of the mounting groove. The other end of the first spring is fixedly connected to a limit block. The extension and retraction direction of the first spring is consistent with the axial direction of the mounting groove. The rotation axis of the support wing is located above the second through hole. A limiting groove is provided on the lower end face of the support wing. When the support wing rotates to the unfolded state in the second through hole, the limiting block extends into the limiting groove under the action of the first spring.

4. The construction method of a precast hollow stiffened pile with inward and outward wings according to claim 1, characterized in that: The lower end face of the second through hole is an arc-shaped surface; The lower end face of the second through hole is in contact with the lower end face of the support wing.

5. The construction method for a precast hollow stiffened pile with inward and outward winging as described in claim 1, characterized in that: In the pile driving step, the bottom of the precast hollow rigid pile is sealed before it is placed in the hole.

6. The construction method for a precast hollow stiffened pile with inward and outward winging as described in claim 1, characterized in that: The wing extension device also includes a vertical limiting rod; The lower end of the vertical limiting rod is fixedly installed at one end of the horizontal limiting rod along its length direction, and the length direction of the vertical limiting rod is perpendicular to the length direction of the horizontal limiting rod. When the support wing extension device is placed into the rigid pile body, two side walls of the vertical limiting rod are in contact with the two side walls adjacent to the first through hole.

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