Precast pile end long pile casing pulling and pouring composite pile and construction method
By setting a long guard at the end of the prefabricated pile and grouting simultaneously during the pulling process, the problem of soil reflow and blocking the grouting channel during the penetration process of prefabricated piles is solved, and the pile quality and bearing capacity are improved. Construction is more controllable and saves costs.
Patent Information
- Application Number
- CN202411944338.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-27
- Publication Date
- 2025-02-18
AI Technical Summary
The soil extrusion effect of prefabricated piles is significant during the penetration process, causing soil reflux to block the grouting channel, affecting the pile quality and bearing capacity.
The pile end long guard is used to pull and pour composite piles. By setting up the pile end guard outside the prefabricated pipe pile, and grouting is synchronized during the pulling process of the pile end guard, the pile side secondary reaming and injection are achieved. Slurry.
It effectively avoids the problem of soil reflux blocking the grouting channel, improves the pile quality and bearing capacity, and the construction process is more controllable, grouting is more stable, saving material and transportation costs.
Smart Images
Figure CN119465924A_ABST
Abstract
Description
Technical Field
[0001] The invention belongs to the technical field of composite piles, and in particular relates to a composite pile with a long casing at a prefabricated pile end and a construction method. Background Art
[0002] Pile foundation engineering is an important part of construction engineering. It involves sinking piles into the ground and fixing them deep in the foundation to enhance the bearing capacity and stability of the foundation. It has received increasing attention in recent years.
[0003] At present, foundation piles can be divided into two categories according to the construction method: cast-in-place piles and precast piles. Compared with cast-in-place piles, precast piles have been widely used in the field of construction engineering due to their advantages such as fast construction speed, low cost and high degree of industrialization. However, compared with traditional cast-in-place piles, the single pile bearing capacity of precast piles is relatively low, and the soil squeezing effect is significant during the penetration process; in order to solve the above problems of precast piles, in the prior art, there is a method of fixing an enlarged pile shoe at the bottom of the precast pile and synchronously grouting the pile side to improve the single pile bearing capacity of the precast pile. When the precast pile uses the enlarged pile shoe for pile sinking, a gap will be formed on the side of the pile, which is the grouting channel for synchronous grouting. However, due to the soft soil of soft clay in some coastal areas, during the pile sinking process, the soil squeezed to both sides is very easy to flow back to the gap on the side of the pile, thereby blocking the grouting channel, making the grouting effect poor, greatly affecting the quality of the final pile and the bearing capacity of the pile foundation.
[0004] Therefore, in order to effectively improve the pile quality of prestressed pipe piles with enlarged pile shoes, a prefabricated pile end long casing grouting composite pile and a construction method are urgently needed to solve the above technical problems. Summary of the invention
[0005] In order to solve the above technical problems, the present invention proposes a prefabricated pile end long casing pull-out composite pile and a construction method.
[0006] To achieve the above object, the present invention provides a prefabricated pile end long casing pull-out composite pile, comprising a prefabricated pipe pile, wherein the bottom end of the prefabricated pipe pile is provided with an enlarged pile shoe for expanding the hole, forming the main structure of the composite pile;
[0007] A grouting pipe is coaxially arranged in the inner cavity of the prefabricated pipe pile, the bottom end of the grouting pipe is connected to the enlarged pile shoe, the top end of the grouting pipe extends out of the prefabricated pipe pile, and the grouting pipe injects grout between the outside of the prefabricated pipe pile and the pile hole through the enlarged pile shoe;
[0008] The outer sliding sleeve of the prefabricated pipe pile is provided with a pile end casing, the bottom end of which abuts against the top end of the enlarged pile shoe. During grouting, the pile end casing is simultaneously lifted up to inject grout into the space between the pile end casing and the enlarged pile shoe.
[0009] Preferably, the length of the pile end casing is not less than the length of the prefabricated pipe pile, and the top of the pile end casing is higher than the top of the prefabricated pipe pile when the pile is planted.
[0010] Preferably, a plurality of upper pulling holes are provided at equal intervals on the top of the side wall of the pile end casing, and the upper pulling holes are higher than the top of the prefabricated pipe pile and are used for lifting the pile end casing.
[0011] Preferably, a grouting port and a plurality of slurry outlets connected to the grouting port are provided at the top end of the enlarged pile shoe, the grouting port is arranged at the top end of the enlarged pile shoe and is connected to the grouting pipe, the plurality of slurry outlets are arranged around the grouting port, and the slurry injected by the grouting pipe is discharged from the plurality of slurry outlets.
[0012] Preferably, a plurality of the slurry outlets are arranged around the outer wall of the prefabricated pipe pile.
[0013] Preferably, an enlarged plate is provided at the bottom end of the pile end casing, and the enlarged plate abuts against the top end of the enlarged pile shoe when the pile is planted.
[0014] Preferably, the inner edge of the enlarged plate is fixedly connected to the bottom end of the outer wall of the pile end casing, and the outer wall of the enlarged plate is flush with the outer edge of the top end of the enlarged pile shoe.
[0015] Preferably, a boss is provided at the top of the enlarged pile shoe, and the grouting port is provided on the boss; and the bottom end of the prefabricated pipe pile is sleeved and fixedly connected to the outer wall of the boss.
[0016] The invention also discloses a construction method for a prefabricated pile end long casing extraction and grouting composite pile, comprising the following steps:
[0017] The expanded pile shoe, the grouting pipe and the pile end casing are sequentially installed on the prefabricated pipe pile to form a pile foundation structure, wherein the expanded pile shoe is installed at the bottom of the prefabricated pipe pile, and one end of the grouting pipe is installed on the expanded pile shoe;
[0018] Carry out pile sinking construction on the assembled pile foundation structure and install the pile foundation structure to the designed depth;
[0019] After the pile foundation is sunk into place, the pile end casing outside the precast pile is slowly pulled up. During the pulling out process, the bottom of the pile end casing will expand the pile hole outside the precast pipe pile for the second time, bringing out the soil that flows back from the pile side. While slowly pulling up, grout is injected into the expanded pile shoe through the grouting pipe, and finally injected into the gap formed by the pulling up of the bottom of the pile end casing.
[0020] After the pile end casing is completely pulled out, the void outside the prefabricated pipe pile is completely filled with grouting slurry, the pile is completed, and the equipment can continue to be used for the next pile foundation construction.
[0021] Preferably, during the pile sinking process of the pile foundation mechanism, no grouting is performed and no treatment is done on the surrounding collapsed soil.
[0022] Compared with the prior art, the present invention has the following advantages and technical effects: the present invention discloses a composite pile with a long casing at the end of a prefabricated pile and a construction method thereof. On the basis of the traditional synchronous grouting method on the pile side with an enlarged pile shoe, a pile end casing is added to realize secondary hole expansion on the pile side, effectively avoiding and clearing the soil layer generated by collapse when the pile is planted. At the same time, the enlarged pile shoe is connected to a grouting pipe, so that synchronous grouting of the pile bottom can be realized during the pulling-up of the pile end casing, which can effectively solve the problem of soil backflow blocking the grouting channel due to the collapse of the surrounding soil. In the specific construction process, synchronous grouting is not required during the pile foundation penetration process, but synchronous grouting is carried out during the pulling-up of the pile end casing. Compared with the pile foundation penetration process, the casing pulling-up process is more controllable and the grouting is more stable. During grouting, site soil can be used as raw material to prepare a fluid or semi-fluid waste mud preparation for grouting, which can effectively save material, transportation and other costs and save resources.
[0023] The invention has a simple structure and utilizes the long casing to pull up to solve the problem of surrounding soil collapse blocking the grouting channel during the pile foundation installation process. The construction process is simple and the equipment can be reused, which is beneficial to saving costs and improving the quality of pile foundation. BRIEF DESCRIPTION OF THE DRAWINGS
[0024] The drawings constituting a part of the present application are used to provide a further understanding of the present application. The illustrative embodiments and descriptions of the present application are used to explain the present application and do not constitute an improper limitation on the present application. In the drawings:
[0025] Figure 1 This is a schematic diagram of a prefabricated pile end long casing pull-out composite pile of the present invention;
[0026] Figure 2 This is a view of the composite pile shaft with a long casing at the end of the prefabricated pile of the present invention;
[0027] Figure 3 Enlarged view of the pile shoe shaft for the present invention;
[0028] Figure 4 An enlarged top view of the pile shoe of the present invention;
[0029] Figure 5 It is a schematic diagram of the structure of the pile shoe enlarged in the present invention;
[0030] Figure 6 It is a schematic diagram of the pile end casing of the present invention;
[0031] Figure 7 It is a schematic diagram of the construction method of the prefabricated pile end long casing pull-out composite pile of the present invention;
[0032] In the figure: 1. grouting pipe; 2. pile end casing; 3. prefabricated pipe pile; 4. enlarged pile shoe; 201. upper pull-out hole; 202. enlarged plate; 401. grouting outlet; 402. grouting outlet; 403. grouting channel; 404. boss. DETAILED DESCRIPTION
[0033] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.
[0034] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.
[0035] Reference Figure 1-Figure 7 As shown, this embodiment provides a prefabricated pile end long casing pull-out composite pile, comprising a prefabricated pipe pile 3, the bottom end of the prefabricated pipe pile 3 is provided with an enlarged pile shoe 4 for expanding the hole, forming the main structure of the composite pile;
[0036] A grouting pipe 1 is coaxially arranged in the inner cavity of the prefabricated pipe pile 3. The bottom end of the grouting pipe 1 is connected to the enlarged pile shoe 4. The top end of the grouting pipe 1 extends out of the prefabricated pipe pile 3. The grouting pipe 1 injects grout between the outside of the prefabricated pipe pile 3 and the pile hole through the enlarged pile shoe 4.
[0037] The prefabricated pipe pile 3 is provided with a pile end casing 2 on the outer sliding sleeve, and the bottom end of the pile end casing 2 abuts against the top end of the enlarged pile shoe 4. During grouting, the pile end casing 2 is simultaneously lifted up to inject grout into the space between the pile end casing 2 and the enlarged pile shoe 4.
[0038] The present invention discloses a prefabricated pile end long casing pull-out composite pile and a construction method. On the basis of the traditional synchronous grouting method on the pile side with an enlarged pile shoe 4, a pile end casing 2 is added to achieve secondary hole expansion on the pile side, effectively avoiding and clearing the soil layer generated by collapse when the pile is planted. At the same time, the enlarged pile shoe 4 is connected to a grouting pipe 1, so that synchronous grouting of the pile bottom can be achieved during the pulling-up process of the pile end casing 2, which can effectively solve the problem of soil backflow blocking the grouting channel 403 due to the collapse of the surrounding soil. In the specific construction process, synchronous grouting is not required during the pile foundation penetration process, but synchronous grouting is carried out during the pulling-up process of the pile end casing 2. Compared with the pile foundation penetration process, the casing pulling-up process is more controllable and the grouting is more stable. During grouting, site soil can be used as raw material to prepare a fluid or semi-fluid waste mud preparation for grouting, which can effectively save costs such as materials and transportation and save resources. The invention has a simple structure and utilizes the long casing to pull up to solve the problem of surrounding soil collapse blocking the grouting channel 403 during the pile foundation installation process. The construction process is simple and the equipment can be reused, which is beneficial to saving costs and improving the quality of pile foundation.
[0039] In one embodiment of the present application, the cross section of the prefabricated pipe pile 3 is circular.
[0040] In one embodiment of the present application, the expanded pile shoe 4 is a conical structure welded to the bottom of the prefabricated pipe pile 3, and its cross-section is larger than that of the pipe pile, so that the hole can be expanded during the penetration of the pipe pile.
[0041] In one embodiment of the present application, the bottom end of the grouting pipe 1 is fixedly connected to and communicated with the top end of the enlarged pile shoe 4, and subsequently, the slurry can be injected into the gap on the pile side through the enlarged pile shoe 4 by high-pressure grouting.
[0042] In a further optimized solution, the length of the pile end casing 2 is not less than the length of the prefabricated pipe pile 3, and the top of the pile end casing 2 is higher than the top of the prefabricated pipe pile 3 when the pile is planted. The inner diameter of the pile end casing 2 is adapted and fitted to the outer wall of the prefabricated pipe pile 3. Before the pile foundation is installed, the pile end casing 2 is put on the outside of the prefabricated pipe pile 3 and penetrated into the ground with the prefabricated pipe pile 3; the length of the pile end casing 2 is not less than the length of the prefabricated pipe pile 3, which is convenient for control.
[0043] Further optimization scheme, a plurality of upper pulling holes 201 are evenly spaced at the top of the side wall of the pile end casing 2, and the upper pulling holes 201 are higher than the top of the prefabricated pipe pile 3, and are used to lift the pile end casing 2. A plurality of upper pulling holes 201 are evenly spaced around the top side wall of the pile end casing 2, and after the prefabricated pipe pile 3 reaches the installation depth, it can be pulled out by a crane, and then the soil flowing back around can be brought out synchronously, realizing secondary hole expansion.
[0044] Further optimization scheme, the top of the enlarged pile shoe 4 is provided with a grouting port 402 and a plurality of grouting outlets 401 connected with the grouting port 402, the grouting port 402 is arranged at the top of the enlarged pile shoe 4 and connected with the grouting pipe 1, a plurality of grouting outlets 401 are arranged around the grouting port 402, and the slurry injected by the grouting pipe 1 is discharged from the plurality of grouting outlets 401. The grouting port 402 is arranged at the top center of the enlarged pile shoe 4, and the grouting pipe 1 can be detached in the grouting port 402; the top of the enlarged pile shoe 4 is provided with a plurality of grouting outlets 401, the grouting outlets 401 are arranged around the grouting port 402, and the grouting port 402 is respectively connected with the grouting port 402 through the grouting channels 403 arranged in the enlarged pile shoe 4; during grouting, the slurry injected into the grouting port 402 by the grouting pipe 1 is transferred to the grouting outlet 401 through the grouting channel 403, and is discharged through the grouting outlet 401, and is filled into the space formed by the outer wall of the prefabricated pipe pile 3 and the pile hole, so as to realize grouting.
[0045] In one embodiment of the present application, a total of four slurry outlets 401 of the present application are provided, and the four slurry outlets 401 are arranged around the grouting port 402 at equal intervals.
[0046] In a further optimized solution, a plurality of slurry outlets 401 are arranged around the outer wall of the prefabricated pipe pile 3. In this solution, during grouting, the slurry flowing out of the slurry outlets 401 is outside the prefabricated pipe pile 3, so that the injected slurry can fill the gap on the side of the pile.
[0047] To further optimize the solution, an expansion plate 202 is provided at the bottom end of the pile end casing 2, and the expansion plate 202 abuts against the top end of the expanded pile shoe 4 when the pile is planted; the inner edge of the expansion plate 202 is fixed to the bottom end of the outer wall of the pile end casing 2, and the outer wall of the expansion plate 202 is flush with the top outer edge of the expanded pile shoe 4. The slurry outlet 401 is located on the outer wall of the prefabricated pipe pile 3, and the expansion plate 202 is fixedly connected to the bottom end of the outer wall of the pile end casing 2. The half cross-section of the structure formed by the pile end casing 2 and the expansion plate 202 at the bottom is L-shaped, and the outer wall of the expansion plate 202 is of equal diameter to the outer edge of the expansion pile shoe 4; before the pile foundation is installed, the pile end casing 2 is put onto the outside of the prefabricated pipe pile 3 so that the expansion plate 202 rests against the top of the expansion pile shoe 4 to block the slurry outlet 401 to prevent the soil caused by pile sinking and collapse from blocking the slurry outlet 401; after the prefabricated pipe pile 3 reaches the installation depth, the pile end casing 2 is pulled out by a crane, and then the soil flowing back from all around can be simultaneously brought out to achieve secondary hole expansion.
[0048] Further optimization scheme, the top of the enlarged pile shoe 4 is provided with a boss 404, and the grouting port 402 is provided on the boss 404; the bottom end of the prefabricated pipe pile 3 is sleeved and fixedly connected to the outer wall of the boss 404. The boss 404 is provided at the top of the enlarged pile shoe 4, which facilitates the positioning and welding of the prefabricated pipe pile 3 and the enlarged pile shoe 4, and improves the bonding strength between the two; the grouting port 402 is opened on the boss 404, which is convenient for positioning and assembly.
[0049] The invention also discloses a construction method for a prefabricated pile end long casing extraction and grouting composite pile, comprising the following steps:
[0050] Construction preparation stage: the enlarged pile shoe 4, the grouting pipe 1 and the casing are installed on the prefabricated pipe pile 3 in sequence, wherein the enlarged pile shoe 4 is installed at the bottom of the prefabricated pipe pile 3, and one end of the grouting pipe 1 is installed at the grouting port 402 of the enlarged pile shoe 4;
[0051] Pile sinking stage: conventional pipe pile construction techniques such as static pressure method and hammer method are used to sink piles and install the pile foundation to the specified depth. During this period, no grouting is performed and no treatment of surrounding soil collapse is done.
[0052] Secondary hole expansion and synchronous grouting stage: After the pile foundation is sunk into place, the long casing at the end of the precast pile is slowly pulled out by connecting the upper pull-out hole 201 on the long casing at the pile end with a crane. During the pulling-out process, the disc at the bottom of the casing will perform secondary hole expansion on the side of the precast pile to bring out the soil that flows back from the pile side. During the slow upward pulling process, the slurry is injected into the grouting pipe 1 by the high-pressure grouting method, and then injected into the grouting channel 403 in the expanded pile shoe 4 by the grouting pipe 1, and finally injected into the gap formed by the upward pulling at the bottom of the casing, finally achieving a good grouting effect.
[0053] Pile formation: After the pile end casing 2 is completely pulled out, the gap on the pile side is completely filled with grouting slurry, the pile formation is completed, and the equipment can continue to be used for the next pile foundation construction.
[0054] In the description of the present invention, it should be understood that the terms "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside" and "outside" etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.
[0055] The embodiments described above are only descriptions of the preferred modes of the present invention, and are not intended to limit the scope of the present invention. Without departing from the design spirit of the present invention, various modifications and improvements made to the technical solutions of the present invention by ordinary technicians in this field should all fall within the protection scope determined by the claims of the present invention.
Claims
1. A prefabricated pile end long casing pull-out composite pile, characterized in that: It comprises a prefabricated pipe pile (3), wherein the bottom end of the prefabricated pipe pile (3) is provided with an enlarged pile shoe (4) for expanding the hole, thereby forming the main structure of the composite pile; A grouting pipe (1) is coaxially arranged in the inner cavity of the prefabricated pipe pile (3); the bottom end of the grouting pipe (1) is connected to the enlarged pile shoe (4); the top end of the grouting pipe (1) extends out of the prefabricated pipe pile (3); and the grouting pipe (1) injects grout between the outside of the prefabricated pipe pile (3) and the pile hole through the enlarged pile shoe (4); The outer sliding sleeve of the prefabricated pipe pile (3) is provided with a pile end casing (2), the bottom end of the pile end casing (2) is in contact with the top end of the enlarged pile shoe (4), and the pile end casing (2) is simultaneously lifted up during grouting, and grouting is injected into the space between the pile end casing (2) and the enlarged pile shoe (4).
2. The prefabricated pile end long casing grouting composite pile according to claim 1, characterized in that: The length of the pile end casing (2) is not less than the length of the prefabricated pipe pile (3), and when the pile is planted, the top of the pile end casing (2) is higher than the top of the prefabricated pipe pile (3).
3. The prefabricated pile end long casing grouting composite pile according to claim 2, characterized in that: A plurality of upper pulling holes (201) are provided at equal intervals on the top of the side wall of the pile end casing (2). The upper pulling holes (201) are higher than the top of the prefabricated pipe pile (3) and are used for lifting the pile end casing (2).
4. The prefabricated pile end long casing grouting composite pile according to claim 1, characterized in that: The top of the enlarged pile shoe (4) is provided with a grouting port (402) and a plurality of slurry outlets (401) connected to the grouting port (402); the grouting port (402) is arranged at the top of the enlarged pile shoe (4) and is connected to the grouting pipe (1); the plurality of slurry outlets (401) are arranged around the grouting port (402); and the slurry injected from the grouting pipe (1) is discharged from the plurality of slurry outlets (401).
5. The prefabricated pile end long casing grouting composite pile according to claim 4, characterized in that: A plurality of slurry outlets (401) are arranged around the outer wall of the prefabricated pipe pile (3).
6. The prefabricated pile end long casing grouting composite pile according to claim 4, characterized in that: An enlarged plate (202) is provided at the bottom end of the pile end casing (2), and when the pile is planted, the enlarged plate (202) abuts against the top end of the enlarged pile shoe (4).
7. The prefabricated pile end long casing pull-out composite pile according to claim 6, characterized in that: The inner edge of the enlarged plate (202) is fixedly connected to the bottom end of the outer wall of the pile end casing (2), and the outer wall of the enlarged plate (202) is flush with the outer edge of the top end of the enlarged pile shoe (4).
8. The prefabricated pile end long casing grouting composite pile according to claim 4, characterized in that: The top end of the enlarged pile shoe (4) is provided with a boss (404), and the grouting port (402) is provided on the boss (404); the bottom end of the prefabricated pipe pile (3) is sleeved and fixedly connected to the outer wall of the boss (404).
9. A method for constructing a precast pile end long casing pull-out composite pile, according to any one of claims 1 to 8, characterized in that The following steps are involved: The enlarged pile shoe (4), the grouting pipe (1) and the pile end casing (2) are sequentially installed on the prefabricated pipe pile (3) to form a pile foundation structure, wherein the enlarged pile shoe (4) is installed at the bottom of the prefabricated pipe pile (3), and one end of the grouting pipe (1) is installed on the enlarged pile shoe (4); Carry out pile sinking construction on the assembled pile foundation structure and install the pile foundation structure to the designed depth; After the pile foundation is sunk into place, the pile end casing (2) outside the prefabricated pile is slowly pulled up. During the pulling out process, the bottom of the pile end casing (2) will perform secondary expansion on the pile hole outside the prefabricated pipe pile (3) to bring out the soil that flows back from the pile side. While slowly pulling up, grout is injected from the grouting pipe (1) into the expanded pile shoe (4), and finally injected into the gap formed by the pulling up of the bottom of the pile end casing (2). After the pile end casing (2) is completely pulled out, the outer space of the prefabricated pipe pile (3) is completely filled with grouting slurry, the pile formation is completed, and the equipment can continue to be used for the next pile foundation construction.
10. The method for constructing a composite pile with a long casing at the end of a precast pile according to claim 9, characterized in that: During the pile sinking process of the pile foundation mechanism, no grouting is carried out and the collapsed soil around is not dealt with.