A pile end combined extrusion grouting construction method for precast solid piles

Abstract

The present application relates to a kind of pile end combined extrusion grouting construction method for prefabricated solid pile, comprising the following construction steps: S1, the assembled pile end extrusion grouting device is installed on the bottom end plate of the last section of prefabricated solid pile;S2, pile body and each pipeline are connected respectively, and according to the requirement of on-site construction, different pile driving mode is used to form pile;S3, after pile body maintenance 1-3 days, the cement soil or undisturbed soil body at the bottom of foundation pile is extruded and compacted by controlling pile end extrusion grouting device, and pile bottom extrusion area is formed;S4, high pressure grouting device carries out high pressure grouting to splitting space and pile end extrusion grouting device inside, and grout returns along prefabricated pile sidewall, and forms grouting reinforced area;The present application aims at improving the end bearing force of foundation pile and reducing construction cost.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of pile foundation engineering construction, and particularly relates to a pile end combined compaction grouting construction method for a prefabricated solid pile. BACKGROUND

[0002] The prefabricated solid pile is a common pile type used in engineering, and has the advantages of high construction efficiency and low cost. However, there are some objective deficiencies that limit its application. Although the prefabricated solid pile is processed in a factory, the pile body quality is well guaranteed, but due to some influencing factors of site geological conditions, the pile body strength cannot be fully utilized, resulting in waste of materials. In the process of pile sinking by using static pressure and other methods, the soil squeezing effect is serious, and due to the stratum conditions, some strata are difficult to penetrate, which limits the application place. In view of the above technical problems, the present application provides a pile end combined compaction grouting construction method for a prefabricated solid pile and a pile end combined compaction grouting system matched with the construction method, and proposes a hydraulic compaction grouting device for improving the pile end bearing capacity by compaction grouting of the pile end soil, and simultaneously combines different pile planting methods to reduce the soil squeezing effect, solves the problem of difficult penetration in special strata, expands the use range of the prefabricated solid pile, and redefines the action mechanism. SUMMARY

[0003] The present application aims to overcome the deficiencies in the prior art, and provides a pile end combined compaction grouting construction method for a prefabricated solid pile. The construction method is used by adding a hydraulic compaction grouting device to the prefabricated solid pile, the original soil at the pile bottom is compacted to improve its bearing capacity, high-pressure grouting is carried out in the pore space formed, the pile bottom is further reinforced, and the bearing capacity of the pile body is improved.

[0004] The purpose of the present application is achieved by the following technical scheme, that is, a pile end combined compaction grouting construction method for a prefabricated solid pile, which comprises the following construction steps:

[0005] S1, the hydraulic extrusion unit, the upper bearing plate, the lower pressing plate, the outer sleeve steel cylinder, the transverse hydraulic pipeline, the transverse grouting pipeline and the one-way grouting valve are assembled to form a pile end extrusion grouting device installed on the bottom end plate of the last section of the prefabricated solid pile, the lower pressing plate is fixedly connected with the outer sleeve steel cylinder, the outer sleeve steel cylinder is fixed with the upper bearing plate through the lifting anti-disengagement device, at least one hydraulic extrusion unit is installed between the upper bearing plate and the lower pressing plate, the hydraulic extrusion unit is communicated with the pile side hydraulic oil pipe of the hydraulic device through the transverse hydraulic pipeline; the upper bearing plate is connected with the transverse grouting pipeline, one end of the transverse grouting pipeline is connected with the one-way grouting valve, the other end of the transverse grouting pipeline is communicated with the high-pressure grouting device through the pile side grouting pipe; and the pile side grouting pipe and the pile side hydraulic oil pipe are temporarily fixed on the side wall of the prefabricated solid pile to be implanted by using the annular clamp;

[0006] S2, according to the requirements of the site construction, such as static pressure or hammering pile sinking mode, the pile tip needs to be installed at the bottom of the pile end extrusion grouting device, before the prefabricated solid pile enters the soil, the outer sleeve steel cylinder and the upper bearing plate are disconnected through the lifting anti-disengagement device, the prefabricated solid pile is completed by the static pressure or hammering pile sinking mode through the pile tip, and the prefabricated solid pile, the pile side hydraulic oil pipe and the pile side grouting pipe are independently connected and fixed in sequence according to the pile sinking sequence, the annular clamp is tightened after the pile connection is completed, until the pile top elevation is reached, and the protection of the oil pipe and the grouting pipe is good after the pile sinking is completed;

[0007] If the pile sinking process is the method of drilling, mixing pile, rotary jet pile construction and then inserting the core pile, the formed hole diameter is required to be greater than the pile diameter of the prefabricated pile, and the prefabricated pile sinking is required to be completed within 6h after the drilling, mixing pile and rotary jet pile construction; before the prefabricated solid pile enters the soil, the outer sleeve steel cylinder and the upper bearing plate are disconnected through the lifting anti-disengagement device, and the prefabricated solid pile, the pile side hydraulic oil pipe and the pile side grouting pipe are independently connected and fixed in sequence according to the pile sinking sequence, the annular clamp is tightened after the pile connection is completed, until the pile top elevation is reached, and the protection of the oil pipe and the grouting pipe is good after the pile sinking is completed;

[0008] S3, after the pile body is maintained for 1-3 days, the high-pressure grouting pump in the high-pressure grouting device is communicated with the pile side grouting pipe through the external grouting pipe, the hydraulic station in the hydraulic device is communicated with the pile side hydraulic oil pipe through the external hydraulic oil pipe, the hydraulic drive of the hydraulic station is controlled to drive the hydraulic extrusion unit of the pile end extrusion grouting device to press down, so as to push the lower pressing plate downward, and the soil at the end of the foundation pile is strongly compacted and extruded to form a pile bottom extrusion area;

[0009] S4, after the lower pressing plate is pushed vertically downwards, a transverse splitting space is formed in the bottom supporting part of the pile body, then a high-pressure grouting pump is started, cement slurry reaches the grouting pipeline under the action of pressure, and each grouting hole in the one-way grouting valve is opened under the action of pressure, then high-pressure grouting is carried out in the splitting space of the bottom pile section and the internal part of the pile end compaction grouting device in the jetting range through the one-way grouting valve, and the slurry returns along the outer wall of the pile body and forms a grouting reinforced area;

[0010] S5, after the pile body is maintained for several days, the grouting of the pile bottom compaction area and the grouting reinforced area is stable and solidified, and a complete pile end reinforced pile body is formed.

[0011] Compared with the prior art, the present application has the following advantages: 1. By arranging the pile end compaction grouting device at the pile end of the prefabricated solid pile, the soil at the pile bottom is compacted, the bearing capacity of the pile end bearing layer is improved, the strength of the pile body is fully utilized, the compaction grouting forms a reinforced enlarged end at the pile end, further improves the end bearing force, optimizes the design of the pile foundation, reduces the length of the pile or the number of piles, thereby shortening the construction period and reducing the cost; 2. Meanwhile, the pile end compaction grouting device can be applied to ordinary prefabricated solid piles and solid piles with specially designed grooves reserved on the side, and reasonable selection can be made according to the construction requirements; 3. The construction method can reasonably set the number of hydraulic extrusion units, the accurate pushing pressure and the pushing stroke according to the requirements, and is designed for different strata, thereby saving materials and controlling costs.

[0012] As a preferred, the outer sleeve steel cylinder is a square steel cylinder, the side wall of the outer sleeve steel cylinder is provided with a hydraulic oil pipe protection cover and a grouting pipe protection cover, the hydraulic oil pipe protection cover and the grouting pipe protection cover are located on opposite sides of the outer sleeve steel cylinder, and a first inclined brace reinforcing rib is arranged between the bottom of the hydraulic oil pipe protection cover and the grouting pipe protection cover and the side wall of the outer sleeve steel cylinder; the side wall of the outer sleeve steel cylinder communicating with the hydraulic oil pipe protection cover is provided with a hydraulic oil pipe reserved hole, and the side wall of the outer sleeve steel cylinder communicating with the grouting pipe protection cover is provided with a grouting pipe reserved hole; by arranging the hydraulic oil pipe protection cover and the grouting pipe protection cover, the pipeline can be prevented from being damaged due to large friction with the soil when entering the soil, and the hydraulic oil pipe reserved hole and the grouting pipe reserved hole are arranged on the side wall of the outer sleeve steel cylinder, so that the connection and limiting of the pipeline are facilitated.

[0013] As preferred, the upper surface of the upper bearing plate is provided with at least two positioning pins, by which the pile end extrusion grouting device is positioned and fixed with the bottom end plate of the prefabricated solid pile; the lower surface of the upper bearing plate is provided with a rubber ring for sealing, which is in abutment with the upper end surface of the outer sleeve steel cylinder; the effective positioning can be achieved when the upper bearing plate and the bottom end plate of the prefabricated solid pile are installed, so that the position deviation is avoided, and meanwhile, by providing the rubber ring, the external soil can be prevented from entering the outer sleeve steel cylinder during the pile sinking process, so that the interior of the pile end extrusion grouting device is kept clean.

[0014] As preferred, the hoisting anti-disengagement device comprises an anti-disengagement plate and an anti-disengagement bolt, the anti-disengagement plate is fixed on the lower surface of the upper bearing plate and located outside the outer sleeve steel cylinder, the anti-disengagement plate is provided with a first bolt hole, the sidewall of the outer sleeve steel cylinder is provided with a second bolt hole corresponding to the first bolt hole, and the first bolt hole and the second bolt hole are fixed by the anti-disengagement bolt; in the S2 step, the first bolt hole and the second bolt hole are disengaged by the anti-disengagement bolt, so that the outer sleeve steel cylinder is disengaged from the upper bearing plate; by the above structure, when the pile end extrusion grouting device connected with the prefabricated solid pile is hoisted, the power end of the hydraulic extrusion unit can be prevented from falling off, and meanwhile, the anti-disengagement bolt can be easily pulled out before the pile body enters the soil.

[0015] As preferred, the hydraulic extrusion unit is one, which is located at the central position between the upper bearing plate and the lower pressing plate, and the upper part of the hydraulic extrusion unit is fixed with the upper bearing plate, and the lower part of the hydraulic extrusion unit is fixed with the lower pressing plate by a plurality of second inclined support ribs for support, and the hydraulic extrusion unit is communicated with the pile side hydraulic oil pipe by a transverse hydraulic pipeline; when the standard value of the pile end resistance is small, one hydraulic extrusion unit can be provided, which can greatly reduce the cost, and meanwhile, by providing the second inclined support ribs, the rigidity of the lower pressing plate can be ensured, so that the local concave deformation is avoided.

[0016] As preferred, the hydraulic extrusion unit is at least two, which are located between the upper bearing plate and the lower pressing plate and are distributed in a surrounding and equidistant manner, and the adjacent hydraulic extrusion units are connected in series by the transverse hydraulic pipeline and communicated with the pile side hydraulic oil pipe; when the standard value of the pile end resistance is large, two or more hydraulic extrusion units can be provided to meet the construction requirements, and by the hydraulic extrusion units distributed in a surrounding and equidistant manner, the pressure of the pile end extrusion grouting device is larger and more uniform.

[0017] As preferred, the high-pressure grouting device comprises a high-pressure grouting pump, an external grouting pipe, a pile-side grouting pipe and a one-way grouting valve, the pile-side grouting pipe is provided with a plurality of sections and is fixed by sections, and is fixed on the side wall of the prefabricated solid pile by using a ring clamp, one end of the pile-side grouting pipe is connected with the external grouting pipe, the external grouting pipe is connected with the high-pressure grouting pump, the other end of the pile-side grouting pipe is located at the grouting pipe protection cover and extends into the outer sleeve through the grouting pipe reserved hole and is connected with one end of the transverse grouting pipe, the transverse grouting pipe is fixed below the upper bearing plate, and the other end of the transverse grouting pipe is connected with the one-way grouting valve, a plurality of grouting holes are formed in the side wall of the one-way grouting valve, and a rubber sleeve is sleeved on the outer wall of the valve body located at the grouting holes; through the arrangement of the above structure, the installation and fixation of the pile-side grouting pipe are facilitated, the pile-side grouting pipe is not affected by shaking during installation, the pipe is not pulled off due to friction during pile sinking, the interface of the pile-side grouting pipe is prevented from being damaged through the protection cover, the rubber sleeve is sleeved on the grouting hole of the one-way grouting valve, a plurality of grouting holes can be externally and unidirectionally grouted under the pressure of high-pressure slurry, the grouting hole is prevented from being blocked by external medium before grouting, and the backflow of slurry after grouting is prevented.

[0018] As preferred, the hydraulic device comprises a hydraulic station, an external hydraulic oil pipe and a pile-side hydraulic oil pipe, the pile-side hydraulic oil pipe is provided with a plurality of sections and is fixed by sections, and is fixed on the side wall of the prefabricated solid pile by using a ring clamp, one end of the pile-side hydraulic oil pipe is connected with the external hydraulic oil pipe, the external hydraulic oil pipe is connected with the hydraulic station, the other end of the pile-side hydraulic oil pipe is located at the hydraulic oil pipe protection cover and extends into the outer sleeve through the hydraulic oil pipe reserved hole and communicates with the transverse hydraulic pipe; through the arrangement of the above structure, the installation and fixation of the pile-side hydraulic oil pipe are facilitated, the pile-side hydraulic oil pipe is not affected by shaking during installation, the pipe is not pulled off due to friction during pile sinking, and the interface of the pile-side hydraulic oil pipe is prevented from being damaged through the protection cover.

[0019] As preferred, the lower part of the lower pressing plate is fixed with a steel pile tip or a concrete pile tip, the concrete pile tip is provided with a supporting rib, and the supporting rib is fixedly connected with the lower pressing plate; when the prefabricated pile is sunk by a static pressure or hammering mode, the pile tip can effectively improve the penetration efficiency of the prefabricated solid pile. BRIEF DESCRIPTION OF DRAWINGS

[0020] Figure 1 It is a structure schematic diagram of the pile end combined compaction grouting system of the application.

[0021] Figure 2 It is a structure schematic diagram of the high-pressure grouting device of the application.

[0022] Figure 3 is the hydraulic device structure schematic diagram of the present application.

[0023] Figure 4 is the pile end extrusion grouting device structure schematic diagram of the present application.

[0024] Figure 5 is the upper bearing plate structure schematic diagram of the present application Figure 1 .

[0025] Figure 6 is the upper bearing plate structure schematic diagram of the present application Figure 2 .

[0026] Figure 7 is the structure schematic diagram between the lower pressing plate and the outer sleeve steel cylinder of the present application.

[0027] Figure 8 is the pile end extrusion grouting device structure schematic diagram of the present application in the first embodiment.

[0028] Figure 9 is the pile end extrusion grouting device structure schematic diagram of the present application in the second embodiment.

[0029] Figure 10 is the pile end extrusion grouting device structure schematic diagram of the present application in the third embodiment.

[0030] Figure 11 is the pile end extrusion grouting device structure schematic diagram of the present application with steel pile tip.

[0031] Figure 12 is the prefabricated solid pile and grouting pipe, hydraulic oil pipe fixing structure schematic diagram of the present application.

[0032] Figure 13 is the hydraulic extrusion unit in different arrangement forms of the prefabricated solid pile of the present application.

[0033] Figure 14 is the different form prefabricated solid pile structure sectional view of the present application.

[0034] Figure 15 is the working state schematic diagram of the pile end extrusion grouting device of the present application.

[0035] Figure 16 is the pile end extrusion grouting device effect picture of the present application.

[0036] The reference signs in the drawings are as follows: 100, pile end extrusion grouting device; 200, prefabricated solid pile; 300, high-pressure grouting device; 400, hydraulic device; 600, splitting space; 700, grouting reinforcement area; 800, pile bottom extrusion area; 900, annular clamp; 101, upper bearing plate; 102, lower pressing plate; 103, outer sleeve steel cylinder; 104, hydraulic extrusion unit; 105, hoisting anti-falling device; 106, transverse hydraulic pipeline; 107, first inclined support reinforcing rib; 108, positioning pin; 109, rubber ring; 110, steel pile tip; 111, concrete pile tip; 112, supporting rib; 113, second inclined support reinforcing rib; 201, grouting pipe reserved groove; 202, hydraulic oil pipe reserved groove; 301, high-pressure grouting pump; 302, external grouting pipe; 303, pile side grouting pipe; 304, one-way grouting valve; 305, grouting hole; 306, rubber sleeve; 307, transverse grouting pipeline; 103-1, hydraulic oil pipe protection cover; 103-2, grouting pipe protection cover; 103-3, hydraulic oil pipe reserved hole; 103-4, grouting pipe reserved hole; 401, hydraulic station; 402, external hydraulic oil pipe; 403, pile side hydraulic oil pipe; 105-1, anti-falling plate; 105-2, anti-falling bolt; 105-3, first bolt hole; 105-4, second bolt hole. DETAILED DESCRIPTION

[0037] The pile end combined extrusion grouting construction method of the present application will be described in detail below in combination with the drawings: The pile end combined extrusion grouting construction method of the present application comprises the following construction steps: As shown in the accompanying drawings, Figures 1 to 16

[0038] ​S1, the hydraulic extrusion unit 104, the upper bearing plate 101, the lower pressing plate 102, the outer sleeve steel cylinder 103, the transverse hydraulic pipeline 106, the transverse grouting pipeline 307 and the one-way grouting valve 304 are assembled to form the pile end extrusion grouting device 100 installed on the bottom end plate of the last section of the prefabricated solid pile 200, the upper bearing plate 101 is welded and connected and fixed between the bottom end plate of the first section of the prefabricated solid pile 200 at the pile bottom through the limiting action of the positioning pin 108, the lower pressing plate 102 is fixedly connected with the outer sleeve steel cylinder 103 through welding, and the outer sleeve steel cylinder 103 is fixed with the upper bearing plate 101 through the hoisting anti-disengagement device 105, at least one hydraulic extrusion unit 104 is installed between the upper bearing plate 101 and the lower pressing plate 102, the size of the hydraulic extrusion unit 104 is determined according to the provided extrusion force and the spatial position, and the hydraulic extrusion units 104 are uniformly distributed in the pile end cross-sectional range of the prefabricated solid pile 200, the hydraulic extrusion unit 104 is communicated with the pile side hydraulic oil pipe 403 of the hydraulic device 400 through the transverse hydraulic pipeline 106; the transverse grouting pipeline 307 is connected with the one-way grouting valve 304 at one end, and the other end of the transverse grouting pipeline 307 is communicated with the high-pressure grouting device 300 through the pile side grouting pipe 303; and the pile side grouting pipe 303 and the pile side hydraulic oil pipe 403 are temporarily fixed on the side wall of the prefabricated solid pile 200 to be implanted by using the annular clamp 900; and the outer diameter of the pile end extrusion grouting device 100 is greater than the outer diameter of the prefabricated solid pile 200 composed of the pile side grouting pipe 303 and the pile side hydraulic oil pipe 403; to prevent the pipeline from being damaged due to large friction with the soil when entering the soil;

[0039] S2, according to the requirements of the site construction, such as the static pressure or hammering pile sinking mode, the pile tip needs to be installed at the bottom of the pile end extrusion grouting device 100, before the prefabricated solid pile 200 enters the soil, the outer sleeve steel cylinder 103 is disconnected with the upper bearing plate 101 through the hoisting anti-disengagement device 105, the prefabricated solid pile 200 is completed by sinking the pile through the pile tip and using the static pressure or hammering pile sinking mode; and the prefabricated solid pile 200, the pile side hydraulic oil pipe 403 and the pile side grouting pipe 303 are separately connected and fixed according to the sinking sequence, the annular clamp 900 is tightened around each pipeline after the pile connection is completed, until the pile top elevation is reached, and the protection of the oil pipe and the grouting pipe is completed after the pile sinking is completed;

[0040] If the pile sinking process is the way of pre-grouting by drilling, mixing pile, jet grouting pile construction after inserting core pile, the formed hole diameter is required to be larger than the pile diameter of the prefabricated pile, and the pile sinking of the prefabricated pile is required to be performed within 6 hours after the construction of pre-grouting by drilling, mixing pile, jet grouting pile. Before the prefabricated solid pile 200 enters the soil, the outer sleeve steel cylinder 103 is disconnected from the upper bearing plate 101 through the hoisting anti-disengagement device 105, and the prefabricated solid pile 200, the pile side hydraulic oil pipe 403, and the pile side grouting pipe 303 are independently connected and fixed in sections according to the pile sinking order. After the pile connection is completed, the annular clamp 900 is clamped on each pipe, until the pile top elevation is reached, and the protection of the oil pipe and the grouting pipe is completed after the pile sinking is completed.

[0041] S3, after the pile body is maintained for 1-3 days, the high-pressure grouting pump 301 in the high-pressure grouting device 300 is connected to the pile side grouting pipe 303 through the external grouting pipe 302, and the hydraulic station 401 in the hydraulic device 400 is connected to the pile side hydraulic oil pipe 403 through the external hydraulic oil pipe 402. The hydraulic station 401 controls the downward pressing of each hydraulic extrusion unit 104 of the pile end extrusion grouting device 100, and then pushes the downward pressing plate 102 downward, and strongly compacts and extrudes the soil at the end of the foundation pile, to form a pile bottom extrusion area 800.

[0042] S4, after the downward pressing plate 102 is pushed vertically downward, the bottom of the pile body is expanded to form a transverse splitting space 600. Then the high-pressure grouting pump 301 is started, the cement slurry reaches the grouting pipe under pressure, and the grouting holes 305 in the one-way grouting valve 304 are opened under pressure. Then the one-way grouting valve 304 performs high-pressure grouting in the jet grouting range to the splitting space 600 of the bottom pile section and the interior of the pile end extrusion grouting device 100, and the slurry returns along the outer wall of the pile body and forms a grouting reinforced area 700.

[0043] S5, after the pile body is maintained for several days, the pile bottom extrusion area 800 and the grouting reinforced area 700 are grouted and solidified to form a complete pile end reinforced pile body.

[0044] The prefabricated solid pile 200 connected to the pile end extrusion grouting device 100 can be a common concrete prefabricated solid square pile, a triangular pile, or a specially designed prefabricated solid pile with a grouting pipe reserved groove 201 and a hydraulic oil pipe reserved groove 202. Since the prefabricated solid square pile is widely used, the pile end extrusion grouting device is optimized for this type of pile to further expand its application range.

[0045] As shown in FIG. 1, the pile end extrusion grouting device 100 is connected to the prefabricated solid pile 200 through the upper bearing plate 101, and the pile end extrusion grouting device 100 is connected to the pile side hydraulic oil pipe 403 and the pile side grouting pipe 303 through the external hydraulic oil pipe 402 and the external grouting pipe 302. Figure 7As shown, the outer sleeve steel cylinder 103 is a square steel cylinder, and the side wall of the outer sleeve steel cylinder 103 is provided with a hydraulic oil pipe protection cover 103-1 and a grouting pipe protection cover 103-2, the hydraulic oil pipe protection cover 103-1 and the grouting pipe protection cover 103-2 are located at opposite sides of the outer sleeve steel cylinder 103, and a first inclined brace reinforcing rib 107 is arranged between the bottom of the hydraulic oil pipe protection cover 103-1 and the grouting pipe protection cover 103-2 and the side wall of the outer sleeve steel cylinder 103; the side wall of the outer sleeve steel cylinder 103 communicating with the hydraulic oil pipe protection cover 103-1 is provided with a hydraulic oil pipe reserved hole 103-3, and the side wall of the outer sleeve steel cylinder 103 communicating with the grouting pipe protection cover 103-2 is provided with a grouting pipe reserved hole 103-4. The functions of the above-mentioned protection covers are to protect the grouting pipe and the hydraulic oil pipe from deformation or even breakage caused by the extrusion of the soil during the pile sinking process; by arranging the reserved holes, space is provided for the grouting pipe and the hydraulic oil pipe to extend into the outer sleeve steel cylinder 103, and at the same time, the soil is prevented from entering the inside of the outer sleeve steel cylinder.

[0046] As shown in the accompanying drawings, Figure 5 , 6 As shown in the accompanying drawings, the upper surface of the upper bearing plate 101 is provided with at least two positioning pins 108, generally four positioning pins 108, which are evenly distributed around the center of the upper bearing plate 101, and the pile end extrusion grouting device 100 and the bottom end plate of the prefabricated solid pile 200 are positioned and fixed through the positioning pins 108; the lower surface of the upper bearing plate 101 is provided with a rubber ring 109 for sealing, the rubber ring 109 abuts against the upper end surface of the outer sleeve steel cylinder 103 and forms a closed structure, preventing the entry of external soil during the pile sinking process and ensuring the cleanliness of the inside of the pile end extrusion grouting device 100.

[0047] As shown in the accompanying drawings, Figure 8 The hoisting anti-falling device 105 includes an anti-falling plate 105-1 and an anti-falling bolt 105-2, the anti-falling plate 105-1 is fixed on the lower surface of the upper bearing plate 101 and located outside the outer sleeve steel cylinder 103, the anti-falling plate 105-1 is provided with a first bolt hole 105-3, the side wall of the outer sleeve steel cylinder 103 corresponding to the first bolt hole 105-3 is provided with a second bolt hole 105-4, and the first bolt hole 105-3 and the second bolt hole 105-4 are fixed by the anti-falling bolt 105-2; the hydraulic piston rod in the hydraulic extrusion unit 104 can be prevented from falling off during hoisting, and the anti-falling bolt 105-2 is pulled out before the pile body enters the soil, so that the upper part of the outer sleeve steel cylinder 103 is in contact with the rubber ring 109 but not connected, and the inside of the pile end extrusion grouting device 100 is sealed and isolated from the outside.

[0048] The anti-falling plate 105-1 in the above is located at opposite sides of the outer sleeve steel cylinder 103 and is cross-shaped distributed between the hydraulic oil pipe protection cover 103-1 and the grouting pipe protection cover 103-2 at opposite sides of the outer sleeve steel cylinder 103, which makes the installation more convenient and the structural stability better.

[0049] As shown in the accompanying drawings Figure 13 The hydraulic extrusion unit 104 is one, which is located at the center between the upper support plate 101 and the lower pressing plate 102, and the upper part of the hydraulic extrusion unit 104 is fixed to the upper support plate 101 by welding, and the lower part of the hydraulic extrusion unit 104 is fixed to the lower pressing plate 102 by welding, and a plurality of second inclined support ribs 113 are arranged between the lower part of the hydraulic extrusion unit 104 and the lower pressing plate 102 to provide support, and the hydraulic extrusion unit 104 is communicated with the pile side hydraulic oil pipe 403 through the transverse hydraulic pipeline 106.

[0050] As shown in the accompanying drawings Figure 13 The hydraulic extrusion unit 104 is at least two, such as two, three or four, which is located between the upper support plate 101 and the lower pressing plate 102 and is distributed in a ring shape at equal intervals, and the adjacent hydraulic extrusion units 104 are connected in series through the transverse hydraulic pipeline 106 and are communicated with the pile side hydraulic oil pipe 403.

[0051] The hydraulic extrusion unit 104 adopts an oil cylinder, and each hydraulic extrusion unit 104 is connected in series through the transverse hydraulic pipeline 106 to provide hydraulic power, and the hydraulic extrusion unit 104 generates pressure inside after being started by the hydraulic station 401, and the hydraulic piston rod extends downward to drive the lower pressing plate 102 to extrude the lower soil body, thereby improving the bearing capacity of the soil body at this place, and at the same time, the hydraulic extrusion unit 104 will cause the pile body to produce a crack space 600 when it is expanded, which provides a directional space for the subsequent grout injection, so as not to affect the grouting effect.

[0052] The high-pressure grouting device 300 comprises a high-pressure grouting pump 301, an external grouting pipe 302, a pile-side grouting pipe 303 and a one-way grouting valve 304. The pile-side grouting pipe 303 is provided with a plurality of sections and is fixed by sections. The pile-side grouting pipe 303 is fixed on the side wall of the prefabricated solid pile 200 by using the annular clamp 900. After the pile connection and the connection of the pile-side grouting pipe 303 are completed, the annular clamp 900 is fastened to prevent the pile-side grouting pipe 303 from falling off or breaking due to friction with the soil during the pile sinking process. Generally, the length of the pile-side grouting pipe 303 is slightly greater than the length of the prefabricated solid pile 200. The pile-side grouting pipe 303 is a rigid pipe, which is convenient for sectional installation. One end of the pile-side grouting pipe 303 is connected with the external grouting pipe 302. The external grouting pipe 302 is connected with the high-pressure grouting pump 301. The other end of the pile-side grouting pipe 303 is located at the grouting pipe protection cover 103-2 and extends into the outer sleeve steel cylinder 103 through the grouting pipe reserved hole 103-4 and is connected with one end of the transverse grouting pipe 307. The transverse grouting pipe 307 is fixed below the upper bearing plate 101. The other end of the transverse grouting pipe 307 is connected with the one-way grouting valve 304. The bottom of the one-way grouting valve 304 is closed by sealing. A plurality of grouting holes 305 are formed in the side wall of the one-way grouting valve 304. Rubber sleeves 306 are sleeved on the outer wall of the valve body located at the grouting holes 305, forming a one-way grouting device. Under the pressure of high-pressure slurry, the plurality of grouting holes 305 can only grout outward in one direction, avoiding the backflow of slurry.

[0053] The hydraulic device 400 comprises a hydraulic station 401, an external hydraulic oil pipe 402 and a pile-side hydraulic oil pipe 403. The pile-side hydraulic oil pipe 403 is provided with a plurality of sections and is fixed by sections. The pile-side hydraulic oil pipe 403 is fixed on the side wall of the prefabricated solid pile 200 by using the annular clamp 900. After the pile connection and the connection of the pile-side hydraulic oil pipe 403 are completed, the annular clamp 900 is fastened to prevent the pile-side hydraulic oil pipe 403 from falling off or breaking due to friction with the soil during the pile sinking process. Generally, the length of the pile-side hydraulic oil pipe 403 is slightly greater than the length of the prefabricated solid pile 200. The pile-side hydraulic oil pipe 403 is a rigid pipe, which is convenient for sectional installation. One end of the pile-side hydraulic oil pipe 403 is connected with the external hydraulic oil pipe 402. The external hydraulic oil pipe 402 is connected with the hydraulic station 401. The other end of the pile-side hydraulic oil pipe 403 is located at the hydraulic oil pipe protection cover 103-1 and extends into the outer sleeve steel cylinder 103 through the hydraulic oil pipe reserved hole 103-3 and communicates with the transverse hydraulic pipe 106.

[0054] In the process of pile sinking by static pressure or hammering, the lower part of the lower pressing plate 102 is fixed with a steel pile tip 110 or a concrete pile tip 111, the steel pile tip 110 is generally a cross-shaped pile tip; the concrete pile tip 111 is provided with a supporting rib 112, which is fixedly connected with the lower pressing plate 102; if there is a sand layer, gravel, rubble and other soil layers which are difficult to be penetrated by static pressure pile sinking or important facilities, buildings existing around the site, and the environmental protection requirement is very strict, the pile sinking mode of stirring implantation, rotary jet stirring implantation or hole guide implantation of the prefabricated solid pile 200 can be adopted, at this time, the pile tip can not be arranged.

[0055] The cross-sectional form of the prefabricated solid pile 200 can be various forms including but not limited to triangle, square, cross, polygon and the like, and the prefabricated solid pile with different cross-sectional shapes can be selected according to the design requirement.

[0056] Embodiment one

[0057] The following will be further described and illustrated in combination with Figures 1 to 3 , Figures 5 to 7 , Figure 8 , Figure 12 , Figure 13 a、 Figure 14 a、 Figures 15 to 16 The engineering background of the present embodiment is a new type of industrial park standard office building in offshore area, the pile type adopts equal core rotary jet pile plus solid prefabricated square pile, the rotary jet pile is implanted with the solid prefabricated square pile after completion, the square pile is 30 m long, the square pile side length is 400 mm, which is a common square pile, the pile body is not provided with a pipeline reserved groove, the rotary jet pile diameter is 700 mm, the soil layer in the pile length range is silty clay and soft soil, the bearing layer is dense silt, and the standard value of pile end resistance is 1200 kPa.

[0058] As Figure 8 、 Figure 14As shown in Fig. 1, in this embodiment, the pile end extrusion grouting device 100 adopts a hydraulic extrusion unit 104 arranged at the center of the cross section of the solid precast square pile 200. The outer diameter of the hydraulic extrusion unit 104 is 240 mm. The upper part of the hydraulic extrusion unit 104 is fixedly connected with the upper bearing plate 101 by welding. The lower piston rod is fixedly connected with the lower pressing plate 102. The hydraulic extrusion unit 104 is connected with the horizontal hydraulic pipeline 106. The pile side hydraulic oil pipe 403 is connected with the horizontal hydraulic pipeline 106 and extends into the interior of the pile end device through the hydraulic oil pipe reserved hole 103-3 on the outer sleeve steel cylinder 103. The turning part is covered and protected by the hydraulic oil pipe protection cover 103-1 and is connected with the external hydraulic station 401 to form the hydraulic device 400. The pile side grouting pipe 303 is connected with the horizontal grouting pipeline 307 and extends into the interior of the pile end device through the grouting pipe reserved hole 103-4 on the outer sleeve steel cylinder 103. The turning part is covered and protected by the grouting pipe protection cover 103-2 and is connected with the high-pressure grouting pump 301 to form the high-pressure grouting device 300. In this embodiment, the method of constructing the mixing pile first and then implanting the precast solid pile 200 is adopted. When the precast solid pile 200 enters the soil, the soil is relatively soft. Therefore, the precast solid pile 200 is not damaged and the pile end device is not damaged. Figure 12 、 Figure 13 As shown in Fig. 1, the side surface is not slotted and only the grouting pipe and the hydraulic oil pipe are fixed by using the annular clamp 900.

[0059] In this embodiment, the downward pressing capacity of the hydraulic extrusion unit 104 depends on the limit end resistance standard value of the pile end soil and the design parameters and quantity of the hydraulic extrusion unit 104. After the rotary jet pile is maintained for 1-3 days, the extrusion grouting is performed. According to the pile foundation design, the side length of the precast solid pile 200 in this embodiment is 400 mm and the limit bearing capacity of the pile end is 192 kN. The downward pressing force provided by the single hydraulic extrusion unit 104 in this embodiment is about 628 kN. The provided pressing force can effectively compact the pile end soil. At the same time, in order to control the splitting space 600 generated by the extrusion and reasonably control the grouting amount, the stroke of the hydraulic extrusion unit 104 is 25 cm.

[0060] The construction procedure of this embodiment is basically similar to that of the basic embodiment and includes the construction of the rotary jet pile and the static pressure sinking of the precast pile. Therefore, the implementation steps of this embodiment are not repeatedly introduced.

[0061] Embodiment Two

[0062] The following will be described in combination with Figures 1 to 3 、 Figures 5 to 7 、 Figure 9 、 Figure 13 b、 Figure 14 b、 Figures 15 to 16Further illustrate the present application, the embodiment engineering background is a high-rise residential project, the pile length range contains a thicker medium dense silt layer, the static pressure process is difficult to penetrate, the bearing stratum is dense silt, and the standard value of pile end resistance is 1600kPa. The design scheme adopts short core rigid composite pile, wherein the diameter of the mixing pile is 800mm, the pile length is 35m, the square pile length is 32m, the square pile side length is 500mm, it is a special square pile, and the pile body is provided with pipeline reserved grooves.

[0063] As Figure 9 、 Figure 14 b shows that in this embodiment, the pile end extrusion grouting device 100 adopts two hydraulic extrusion units 104, which are arranged in a diagonal and symmetrical manner on the cross section of the solid prefabricated square pile 200. The outer diameter of the hydraulic extrusion unit 104 is 200mm, and the rest of the structure is the same as that of the first embodiment. In this embodiment, the prefabricated solid pile 200 is used in the way of constructing the mixing pile first and then implanting the prefabricated solid pile 200, as shown in Figure 12 、 Figure 13 b shows that the side is slotted, the grouting pipe on each pile body is connected with the hydraulic oil pipe in advance and placed in the grouting pipe reserved groove 201 and the hydraulic oil pipe reserved groove 202, and the grouting pipe and the hydraulic oil pipe are temporarily fixed by using the annular clamp 900. At the same time of connecting the piles, the pipelines are connected and the annular clamp 900 is fastened.

[0064] In this embodiment, the downward pressing capacity of the hydraulic extrusion unit 104 depends on the compressive strength of the cement soil at the pile end and the design parameters and number of the hydraulic extrusion unit 104. According to the pile foundation design, the diameter of the prefabricated solid pile 200 in this embodiment is 400mm, and the extrusion grouting is carried out after the mixing pile is cured for 1-3 days. At this time, the cement soil has not been completely solidified, and the downward pressing force provided by a single hydraulic extrusion unit 104 in this embodiment is about 454kN, which can compress and compact the cement soil according to the design calculation. At the same time, in order to control the reasonable splitting space 600 generated by extrusion and grasp the grouting amount, the stroke of the hydraulic extrusion unit 104 is 20cm.

[0065] The construction procedure of this embodiment is basically similar to that described in the basic embodiment, which includes the construction of the mixing pile and the static pressure sinking of the prefabricated pile. Therefore, the implementation steps of this embodiment will not be repeated.

[0066] Embodiment three

[0067] The following will be described with reference to Figures 1 to 3 、 Figures 5 to 7 、 Figure 10 、 Figure 13 a、 Figure 14 b、 Figures 15 to 16Further illustrate the present application, the engineering background of the embodiment is factory building and attached office building, using static pressure solid precast square pile process, the bearing stratum is medium dense silty clay layer, the standard value of pile end resistance is 1000kPa. Square pile length 27m, square pile side length 500mm, is a special square pile, in order to ensure that the pipeline is not damaged in the process of static pressure, the pipeline reserved groove is arranged on the pile body.

[0068] As Figure 4 , Figure 10 , Figure 14 b, in this embodiment, the pile end extrusion grouting device 100 adopts three hydraulic extrusion units 104, which are uniformly and symmetrically arranged on the cross section of the precast solid square pile 200, the outer diameter of the hydraulic extrusion unit 104 is 160mm, and the rest of the structure is the same as that of embodiment one. In this embodiment, the precast solid square pile 200 is shown in Figure 12 , Figure 13 b, the side is slotted, the grouting pipe on each pile body is connected with the hydraulic oil pipe in advance and placed in the grouting pipe reserved groove 201 and the hydraulic oil pipe reserved groove 202, and the grouting pipe and the hydraulic oil pipe are temporarily fixed by using the annular clamp 900, and the pipelines are connected and the annular clamp 900 is fastened at the same time.

[0069] In this embodiment, the downward pressing capacity of the hydraulic extrusion unit 104 depends on the ultimate end resistance standard value strength of the pile end soil and the design parameters and number of the hydraulic extrusion unit 13. According to the pile foundation design, the precast solid square pile 200 in this embodiment has a side length of 500mm, and the ultimate bearing capacity of the pile end is 250kN. In this embodiment, a single hydraulic extrusion unit 104 can provide a downward pressing force of about 230kN, and the pile end soil can be compressed and extruded according to the design calculation; at the same time, in order to control the crack space generated by extrusion and reasonably grasp the grouting amount, the stroke of the hydraulic extrusion unit 104 is 15cm.

[0070] This embodiment adopts static pressure construction process for pile sinking, as shown in Figure 10 The lower part of the pressing plate 102 of the pile end extrusion grouting device 100 is provided with a concrete pile tip 111, and the concrete pile tip 111 is connected with the pressing plate 102 through the internal support rib 112.

[0071] The construction process of this embodiment is basically similar to that described in the basic embodiment, only including the static pressure pile sinking of the precast solid square pile 200, without the hole digging process such as mixing pile, so the implementation steps of this embodiment will not be introduced again.

[0072] The present application is not limited to the above embodiments, and any change in shape or material composition is not limited to the above embodiments, as long as the structure design provided by the present application is adopted, it is a deformation of the present application, and should be considered within the protection scope of the present application.

Claims

1. A pile end combined extrusion grouting construction method for precast solid piles, characterized in that: The pile end combined extrusion grouting construction method comprises the following construction steps: S1, the hydraulic extrusion unit (104), the upper bearing plate (101), the lower pressing plate (102), the outer sleeve steel cylinder (103), the transverse hydraulic pipeline (106), the transverse grouting pipeline (307) and the one-way grouting valve (304) are assembled to form a pile end extrusion grouting device (100) installed on the bottom end plate of the last section of the prefabricated solid pile (200), the lower pressing plate (102) is fixedly connected with the outer sleeve steel cylinder (103), the outer sleeve steel cylinder (103) is fixedly connected with the upper bearing plate (101) through the lifting anti-disengagement device (105), at least one hydraulic extrusion unit (104) is installed between the upper bearing plate (101) and the lower pressing plate (102), the hydraulic extrusion unit (104) is communicated with the pile side hydraulic oil pipe (403) of the hydraulic device (400) through the transverse hydraulic pipeline (106); the upper bearing plate (101) is connected with the transverse grouting pipeline (307), one end of the transverse grouting pipeline (307) is connected with the one-way grouting valve (304), the other end of the transverse grouting pipeline (307) is communicated with the high-pressure grouting device (300) through the pile side grouting pipe (303); and the pile side grouting pipe (303) and the pile side hydraulic oil pipe (403) are temporarily fixed on the side wall of the prefabricated solid pile (200) to be implanted by using the annular clamp (900); S2, according to the requirements of the site construction, if the pile sinking process is the static pressure or hammering pile sinking mode, the pile tip needs to be installed at the bottom of the pile end extrusion grouting device (100), before the prefabricated solid pile (200) is put into the earth, the outer sleeve steel cylinder (103) is disconnected with the upper bearing plate (101) through the lifting anti-disengagement device (105), the prefabricated solid pile (200) is completed by the static pressure or hammering pile sinking mode through the pile tip; and the prefabricated solid pile (200), the pile side hydraulic oil pipe (403) and the pile side grouting pipe (303) are independently connected and fixed in sections according to the pile sinking sequence, after the pile connection is completed, the annular clamp (900) is tightened on each pipeline, until the pile top elevation is reached, and after the pile sinking is completed, the protection of the oil pipe and the grouting pipe is completed; if the pile sinking process is the mode of first drilling, pre-grouting, mixing pile or rotary jet pile construction and then inserting the core pile, the formed hole diameter is required to be larger than the pile diameter of the prefabricated solid pile, and the prefabricated solid pile is required to be sunk within 6h after the drilling, pre-grouting, mixing pile or rotary jet pile construction; before the prefabricated solid pile (200) is put into the earth, the outer sleeve steel cylinder (103) is disconnected with the upper bearing plate (101) through the lifting anti-disengagement device (105), and the prefabricated solid pile (200), the pile side hydraulic oil pipe (403) and the pile side grouting pipe (303) are independently connected and fixed in sections according to the pile sinking sequence, after the pile connection is completed, the annular clamp (900) is tightened on each pipeline, until the pile top elevation is reached, and after the pile sinking is completed, the protection of the oil pipe and the grouting pipe is completed; S3, after the pile body is maintained for 1-3 days, the high-pressure grouting pump (301) in the high-pressure grouting device (300) is communicated with the pile side grouting pipe (303) through the external grouting pipe (302), the hydraulic station (401) in the hydraulic device (400) is communicated with the pile side hydraulic oil pipe (403) through the external hydraulic oil pipe (402), the hydraulic drive of the hydraulic station (401) is controlled to press down each hydraulic extrusion unit (104) of the pile end extrusion grouting device (100), then the lower pressing plate (102) is pushed downward, and the soil body at the end of the pile is strongly compacted and extruded, so that the pile bottom extrusion area (800) is formed; S4, after the lower pressing plate (102) is pushed vertically downward, the bottom of the pile body is expanded to form a transverse splitting space (600), then the high-pressure grouting pump (301) is started, the cement slurry reaches the grouting pipeline under the action of pressure, and each grouting hole (305) in the one-way grouting valve (304) is opened under the action of pressure, then the one-way grouting valve (304) is used to perform high-pressure grouting in the range of the grouting range to the splitting space (600) of the bottom pile section and the inside of the pile end extrusion grouting device (100), and the slurry returns along the outer sidewall of the pile body and forms a grouting reinforced area (700); S5, after the pile body is maintained for several days, the pile bottom extrusion area (800) and the grouting reinforced area (700) are grouted and solidified to form a complete pile end reinforced pile body; The outer sleeve steel cylinder (103) is a square steel cylinder, the outer sleeve steel cylinder (103) is provided with a hydraulic oil pipe protection cover (103-1) and a grouting pipe protection cover (103-2) on the side wall, the hydraulic oil pipe protection cover (103-1) and the grouting pipe protection cover (103-2) are located on opposite sides of the outer sleeve steel cylinder (103), and a first inclined brace reinforcing rib (107) is arranged between the bottom of the hydraulic oil pipe protection cover (103-1) and the grouting pipe protection cover (103-2) and the side wall of the outer sleeve steel cylinder (103); the outer sleeve steel cylinder (103) is provided with a hydraulic oil pipe reserved hole (103-3) on the side wall in communication with the hydraulic oil pipe protection cover (103-1), and the outer sleeve steel cylinder (103) is provided with a grouting pipe reserved hole (103-4) on the side wall in communication with the grouting pipe protection cover (103-2); The upper surface of the upper bearing plate (101) is provided with at least two positioning pins (108), the pile end extrusion grouting device (100) and the bottom end plate of the prefabricated solid pile (200) are positioned and fixed through the positioning pins (108); the lower surface of the upper bearing plate (101) is provided with a rubber ring (109) for sealing, and the rubber ring (109) abuts against the upper end surface of the outer sleeve steel cylinder (103).

2. The pile tip combined extrusion and grouting construction method for precast solid piles according to claim 1, characterized in that: The lifting anti-disengagement device (105) comprises an anti-disengagement plate (105-1) and an anti-disengagement bolt (105-2), the anti-disengagement plate (105-1) is fixed on the lower surface of the upper bearing plate (101) and located outside the outer sleeve steel cylinder (103), the anti-disengagement plate (105-1) is provided with a first bolt hole (105-3), the side wall of the outer sleeve steel cylinder (103) is provided with a second bolt hole (105-4) corresponding to the first bolt hole (105-3), and the first bolt hole (105-3) and the second bolt hole (105-4) are fixed by the anti-disengagement bolt (105-2); in the S2 step, the first bolt hole (105-3) and the second bolt hole (105-4) are separated by the anti-disengagement bolt (105-2), so that the outer sleeve steel cylinder (103) is separated from the upper bearing plate (101).

3. The pile tip combined extrusion and grouting construction method for precast solid piles according to any one of claims 1 to 2, characterized in that: The hydraulic extrusion unit (104) is one, the hydraulic extrusion unit (104) is located at the center position between the upper bearing plate (101) and the lower pressing plate (102), and the upper part of the hydraulic extrusion unit (104) is fixed with the upper bearing plate (101), and the lower part of the hydraulic extrusion unit (104) is fixed with the lower pressing plate (102) and is supported by a plurality of second inclined support ribs (113). The hydraulic extrusion unit (104) is communicated with the pile side hydraulic oil pipe (403) through the transverse hydraulic pipeline (106).

4. The pile tip combined extrusion and grouting construction method for precast solid pile according to any one of claims 1 to 2, characterized in that: The hydraulic extrusion unit (104) is at least two, the hydraulic extrusion unit (104) is located between the upper bearing plate (101) and the lower pressing plate (102) and is distributed in a surrounding manner, the adjacent hydraulic extrusion units (104) are connected in series through the transverse hydraulic pipeline (106) and communicated with the pile side hydraulic oil pipe (403).

5. The pile tip combined extrusion and grouting construction method for precast solid piles according to claim 1, characterized in that: The high-pressure grouting device (300) comprises a high-pressure grouting pump (301), an external grouting pipe (302), a pile side grouting pipe (303) and a one-way grouting valve (304), the pile side grouting pipe (303) is provided with a plurality of sections and is fixed by section installation, and is fixed on the side wall of the prefabricated solid pile (200) by using a ring clamp (900), one end of the pile side grouting pipe (303) is connected with the external grouting pipe (302), the external grouting pipe (302) is connected with the high-pressure grouting pump (301), the other end of the pile side grouting pipe (303) is located at the grouting pipe protection cover (103-2) and penetrates through the grouting pipe reserved hole (103-4) to extend into the outer sleeve steel cylinder (103) and is connected with one end of the transverse grouting pipeline (307), the transverse grouting pipeline (307) is fixed below the upper bearing plate (101), the other end of the transverse grouting pipeline (307) is connected with the one-way grouting valve (304), a plurality of grouting holes (305) are formed in the side wall of the one-way grouting valve (304), and a rubber sleeve (306) is sleeved on the outer wall of the valve body located in the grouting hole (305).

6. The pile tip combined extrusion and grouting construction method for precast solid piles according to claim 1, characterized in that: The hydraulic device (400) comprises a hydraulic station (401), an external hydraulic oil pipe (402) and a pile side hydraulic oil pipe (403), the pile side hydraulic oil pipe (403) is provided with a plurality of sections, is fixed by sections, is fixed on the side wall of the prefabricated solid pile (200) by using a ring clamp (900), one end of the pile side hydraulic oil pipe (403) is connected with the external hydraulic oil pipe (402), the external hydraulic oil pipe (402) is connected with the hydraulic station (401), the other end of the pile side hydraulic oil pipe (403) is located at the hydraulic oil pipe protection cover (103-1), passes through the hydraulic oil pipe reserved hole (103-3), extends into the outer sleeve steel cylinder (103) and communicates with the transverse hydraulic pipe (106).

7. The pile tip combined extrusion and grouting construction method for precast solid piles according to claim 1, characterized in that: The lower part of the lower pressing plate (102) is fixed with a steel pile tip (110) or a concrete pile tip (111), the concrete pile tip (111) is provided with a supporting rib (112), and the supporting rib (112) is fixedly connected with the lower pressing plate (102).

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