A forepoling structure and a construction method thereof
By using the sleeve joint structure and expansion joint adjustment plate, the problems of misalignment and poor welding quality of inclined steel pipe pile joints were solved, realizing rapid and accurate docking and efficient construction, and improving the safety and efficiency of foundation pit support.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- GREENTOWN REAL ESTATE CONSTR & MANAGEMENT GRP CO LTD
- Filing Date
- 2026-05-21
- Publication Date
- 2026-07-21
AI Technical Summary
In the existing advanced inclined support process, the misalignment of inclined steel pipe pile joints is a prominent problem, and the welding quality is poor, resulting in weak bearing capacity, low construction efficiency, and insufficient safety.
The sleeve joint structure is adopted, and the coaxiality of the back pipe and the front pipe is automatically calibrated by the telescopic adjustment plate to form a closed connection, which simplifies the welding operation and improves the welding quality and efficiency.
It enables rapid and precise connection of inclined steel pipe piles, improves the bearing capacity of the pile body and the safety of the support structure, shortens the foundation pit support period, and reduces construction risks.
Smart Images
Figure CN122428656A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of foundation pit support technology, specifically to an advanced support structure and its construction method. Background Technology
[0002] As the core venue for showcasing the project's image and facilitating transactions, real estate project demonstration areas typically require rapid construction and quick operation. Some demonstration area sales offices include basements that are excavated simultaneously with the initial building phase, placing higher demands on the construction period, safety, and cost-effectiveness of the foundation pit support engineering.
[0003] Advanced inclined bracing is a widely used technology in shallow, large-area foundation pit support. Based on pile support, precast piles are driven obliquely into the pit under static pressure. High-pressure jet grouting or forced grouting is then used around the piles below the foundation slab to form a cement-reinforced structure, ultimately creating a triangular stable support system consisting of piles, inclined bracing piles, and the foundation soil. This technology effectively controls deformation of the support structure and surrounding soil, significantly shortens the construction period, and improves construction efficiency.
[0004] However, existing advanced inclined support technology has significant drawbacks: due to limitations in the precision of construction machinery and construction control methods for inclined pile foundations, joint misalignment is a prominent issue during segmented construction of inclined steel pipe piles. Currently, the commonly used steel pipe piles have a wall thickness of approximately 5mm, making it difficult to precisely align and weld the preceding and following sections at the joint. This results in inconsistent welding quality, creating weak areas in the pile body and posing safety hazards to the foundation pit support. Furthermore, the lack of effective calibration measures during joint connection necessitates significant time for manual alignment, severely reducing construction efficiency and hindering the further promotion and application of this technology. Summary of the Invention
[0005] The purpose of this invention is to overcome the shortcomings of the prior art and provide an advanced support structure and its construction method. By optimizing the joint connection structure of inclined steel pipe piles, the invention solves the problems of difficult connection of inclined steel pipe piles, poor welding quality and slow construction speed in the prior art, realizes rapid and accurate connection of inclined piles, improves the bearing capacity of the pile body and the safety of the support structure, and further shortens the construction period of foundation pit support.
[0006] The present invention is achieved through the following technical solution.
[0007] This invention discloses an advanced support structure, comprising support piles, a capping beam, inclined pile reinforcing piers, inclined piles, and a cement-reinforced body. The capping beam is disposed on top of the support piles, the inclined pile reinforcing piers are fixedly connected to the capping beam, and the inclined piles are connected to the inclined pile reinforcing piers, together forming a triangular stable support system.
[0008] The inclined pile includes a front section pipe, a rear section pipe, and a sleeve joint for coaxially connecting the front section pipe and the rear section pipe. The sleeve joint includes a sleeve, a front section pipe sealing plate, a rear section pipe sealing plate, and several telescopic adjustment plates. The front section pipe sealing plate is welded and fixed to both the sleeve and the front section pipe, and the rear section pipe sealing plate is welded and fixed to both the sleeve and the rear section pipe. Several telescopic adjustment plates are fixedly disposed inside the sleeve and evenly distributed along the circumference of the sleeve. These telescopic adjustment plates apply a force towards the central axis of the sleeve to the rear section pipe inserted into the sleeve, automatically aligning the rear section pipe and the front section pipe coaxially.
[0009] Preferably, both the rear pipe and the front pipe are made of steel pipe, the sleeve is made of steel sleeve, the front pipe sealing plate and the rear pipe semi-circular sealing plate are both made of steel plate, and the telescopic adjustment plate is made of steel plate; alternatively, in addition to steel, iron pipe or other metal materials with similar properties to steel pipe can also be used.
[0010] Furthermore, the telescopic adjustment piece is any steel piece with elastic deformation function, such as a triangular steel piece or an arc-shaped steel piece, preferably a triangular steel piece. One or both ends of the telescopic adjustment piece are welded and fixed to the inner wall of the sleeve, and the protruding part of the telescopic adjustment piece faces the central axis of the sleeve. Utilizing the elastic deformation capability of the triangular steel piece itself, a reaction force pointing towards the center is generated when the rear connecting pipe is inserted, realizing automatic calibration, and at the same time, it can adapt to a certain range of deviations in the outer diameter of the rear connecting pipe.
[0011] Furthermore, the number of the telescopic adjustment plates is 3-6, which can be flexibly selected according to the diameter of the sleeve and the outer diameter of the rear pipe to ensure alignment accuracy and uniform force distribution.
[0012] Furthermore, the front pipe sealing plate and the rear pipe sealing plate are respectively connected at both ends of the sleeve, which facilitates welding and helps to improve welding efficiency.
[0013] Furthermore, both the front pipe sealing plate and the rear pipe sealing plate are annular sealing plates, which are connected to both ends of the sleeve to form a closed joint cavity, thereby improving the integrity and sealing of the joint.
[0014] Furthermore, the rear pipe sealing plate is composed of two symmetrical semi-circular sealing plates spliced together, which facilitates installation from the outside after the rear pipe is inserted into the sleeve, eliminating the need for pre-insertion of the pipe and simplifying the construction process.
[0015] Furthermore, the end of the front section pipe is fixedly equipped with a spiral blade, which facilitates cutting the soil during static pressure insertion and reduces construction resistance; the cement solidification is poured into the soil inside the front section pipe and the surrounding soil, which can significantly enhance the bond between the pile and the soil and improve the pull-out and lateral displacement resistance of the inclined pile.
[0016] On the other hand, the present invention provides a construction method for the above-mentioned advanced support structure, comprising the following steps:
[0017] S1: Weld the front section pipe sealing plate to the front section pipe and the sleeve respectively, and weld multiple telescopic adjustment plates evenly on the inner wall of the sleeve to obtain the front section pipe assembly.
[0018] S2: Press the front section of the pipe assembly into the soil at an angle according to the design until the front section of the pipe reaches the set depth.
[0019] S3: Insert the lower end of the rear connector into the sleeve, and use the multiple telescopic adjustment pieces inside the sleeve to automatically adjust the axis of the rear connector to coincide with the axis of the front pipe to achieve coaxial connection.
[0020] S4: Weld the rear pipe sealing plate to the rear pipe and the sleeve respectively to form an integral inclined pile structure;
[0021] S5: Continue static pressure on the pipe along the design angle until the entire inclined pile reaches the design elevation;
[0022] S6: Pour cement reinforcement into the inside and outside of the front section pipe, and at the same time pour inclined pile reinforcement piers, so that the inclined piles are connected to the capping beam and support piles as a whole through the inclined pile reinforcement piers, thus completing the construction of the advanced support structure.
[0023] Further, in step S4, the two semi-circular sealing plates are fitted onto the outside of the rear pipe and spliced together to form a complete rear pipe sealing plate, and then welded and fixed.
[0024] Furthermore, during welding, the inner ring of the front pipe sealing plate is circumferentially welded to the front pipe, and the outer ring is circumferentially welded to the sleeve. Similarly, the inner ring of the rear pipe sealing plate is circumferentially welded to the rear pipe, and the outer ring is circumferentially welded to the sleeve, forming a continuous and closed weld to ensure the welding strength and sealing performance of the joint.
[0025] The beneficial effects of this invention are:
[0026] By using the expansion joints evenly distributed around the inner circumference of the casing, the coaxiality of the connecting pipe and the front pipe is automatically calibrated by their elastic deformation, eliminating the need for repeated manual adjustments. This solves the problem of large misalignment in traditional joints, ensuring the axial force of the inclined steel pipe pile. The casing joint forms a closed connection structure, with welding positions concentrated at the circular sealing plates at both ends of the casing. This provides a large welding operation space, making it easy to control the weld quality. It avoids the misalignment defects of traditional steel pipe butt welding, resulting in uniform bearing capacity, eliminating weak areas in the pile body, enhancing the stability of the support system, and reducing the safety risks of foundation pit construction.
[0027] The front-end pipe sealing plate, front-end pipe, and sleeve can be prefabricated in the factory. The joint connection process does not require manual calibration, and the welding process is simple and efficient, which significantly speeds up the overall construction progress and balances the construction period and economic benefits. It is suitable for promotion and application in rapid construction projects such as demonstration zones. Attached Figure Description
[0028] To more clearly illustrate the technical solutions in the embodiments of the invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0029] The present invention will be further described below with reference to the accompanying drawings and embodiments.
[0030] Figure 1 This is a cross-sectional view of the advanced support structure of the present invention;
[0031] Figure 2 for Figure 1 A schematic diagram of the vertical cross-section of the steel sleeve joint at point bb;
[0032] Figure 3 for Figure 1 A schematic diagram of the horizontal cross-section of the steel sleeve joint at point aa;
[0033] In the diagram: 1-Support pile; 2-Capping beam; 3-Inclined pile reinforcement pier; 4-Rear pipe; 5-Casing joint; 6-Front section pipe; 7-Cement reinforcement body; 8-Helical blade; 9-Casing; 10-Front section pipe sealing plate; 11-Rear pipe sealing plate; 12-Expansion adjustment plate; 13-Weld. Detailed Implementation
[0034] The following is combined Figures 1-3 The present invention will be described in detail below.
[0035] Example 1:
[0036] An advanced support structure of the present invention, such as Figure 1 It includes support piles 1, capping beams 2, inclined pile reinforcement piers 3, rear pipes 4, sleeve joints 5, front pipes 6, cement reinforcement bodies 7, and spiral blades 8.
[0037] The rear pipe 4, sleeve joint 5, and front pipe 6 constitute a complete inclined steel pipe pile.
[0038] The capping beam 2 is set on top of the support pile 1, the inclined pile reinforcing pier 3 is connected to the capping beam 2, and the inclined pile is connected to the inclined pile reinforcing pier 3.
[0039] The sleeve connector 5 is used to achieve coaxial connection between the front pipe 6 and the rear pipe 4, such as Figure 2 , Figure 3 The sleeve joint 5 includes a sleeve 9, a front pipe sealing plate 10, a rear pipe sealing plate 11, and a telescopic adjustment plate 12.
[0040] In this embodiment, both the rear pipe 4 and the front pipe 6 are made of steel pipe, the sleeve 9 is made of steel sleeve, the front pipe sealing plate 10 and the rear pipe semi-circular sealing plate 11 are both made of steel plate, and the telescopic adjustment plate 12 is made of steel sheet.
[0041] The front pipe sealing plate 10 is welded and fixed to the sleeve 9 and the front pipe 6, such as Figure 3 The weld 13 shown is the welding position. The rear pipe sealing plate 11 is welded and fixed to the sleeve 9 and the rear pipe 4. The front pipe sealing plate 10 and the rear pipe sealing plate 11 are respectively set at both ends of the sleeve 9. The telescopic adjustment piece 12 is a triangular steel piece. The telescopic adjustment piece 12 is fixedly set inside the sleeve 9 and multiple pieces are evenly arranged along the circumference of the sleeve 9. In this embodiment, four telescopic adjustment pieces 12 are set. One end or both ends of the telescopic adjustment piece 12 are welded and fixed to the inner wall of the sleeve 9, and the protruding part in the middle faces the center of the sleeve 9.
[0042] In this embodiment, both the front pipe sealing plate 10 and the rear pipe sealing plate 11 are annular sealing plates. During welding, a circumferential welding method is adopted to form an annular weld 13, which effectively increases the welding area and improves the overall strength of the structure after welding. In other embodiments, the sealing plate can also be selected as a long strip or other arbitrary shape.
[0043] In this embodiment, the rear pipe sealing plate 11 is preferably composed of two semi-circular ring sealing plates, so that it can be inserted into the outside of the rear pipe 4 and welded and fixed to the rear pipe 4 and the sleeve 9.
[0044] In this embodiment, the front section pipe sealing plate 10 is welded to the end of the front section pipe 6, so that the front section pipe 6 does not extend into the sleeve 9, thereby allowing the rear pipe 4 to extend into the sleeve 9 for a longer length, making the overall structure more stable during subsequent welding. In other embodiments, the front section pipe sealing plate 10 can also be welded to a non-end position of the front section pipe 6, so that the end of the front section pipe 6 extends into the sleeve 9. The length of the end of the front section pipe 6 entering the sleeve 9 should be less than half the length of the sleeve 9, to ensure that the rear pipe 4 can cooperate with the protruding position in the middle of the telescopic adjustment piece 12 after it enters. This method is beneficial to improve the welding efficiency between the front section pipe sealing plate 10 and the front section pipe 6.
[0045] The spiral blade 8 is welded to the outer circle of the lower side of the front pipe 6, which facilitates cutting the soil when it is pressed into the ground. The cement solidified body 7 is formed by pouring on the outside and inside of the front pipe 6. The spiral blade 8 can also play a role in stabilizing the connection between the front pipe 6 and the cement solidified body 7.
[0046] Construction steps:
[0047] Factory prefabrication stage:
[0048] In the steel structure processing plant, the front section pipe 6 is cut to the designed length, and the spiral blade 8 is welded to its lower end; the inner ring of the front section pipe sealing plate 10 is welded to the upper outer wall of the front section pipe 6, and the outer ring is welded to the lower end of the sleeve 9. All of the above welding is circumferential welding to form a circumferential weld 13 to ensure welding strength; then, four evenly distributed welding points are marked on the inner wall of the sleeve 9, and four telescopic adjustment plates 12 are welded to the corresponding positions on the inner wall of the sleeve 9 to ensure that the apex of each adjustment plate is on the same circumference.
[0049] On-site construction phase:
[0050] Using a pile driver, the front section pipe 6 is pushed into the soil to a set depth under the pressure of the pile driver. The rear section pipe 4 is then lifted by a crane and inserted into the sleeve 9 to connect with the front section pipe 6. The outer wall of the rear section pipe 4 squeezes the telescopic adjustment plate 12 to produce elastic deformation. The reaction force of the four adjustment plates together pushes the rear section pipe 4 to the center position, automatically achieving coaxial docking with the front section pipe 6. This ensures that the axis of the front section pipe 6 and the rear section pipe 4 are aligned, guaranteeing that the inclined steel pipe pile is subjected to axial force.
[0051] Two semi-circular sealing plates are fitted onto the outside of the rear pipe 4 to form the rear pipe sealing plate 11. The inner ring of the rear pipe sealing plate 11 is welded to the outer circle of the rear pipe 4, and the outer circle of the rear pipe sealing plate 11 is welded to the upper end of the sleeve 9. After welding, an integral steel structure is formed.
[0052] After the weld has cooled, the pile driver pusher continues to advance the pile, and the connecting pipe 4 enters the soil until the design elevation is reached, thus completing the construction of the entire inclined steel pipe pile.
[0053] High-pressure jet grouting is used to inject cement slurry into the interior and periphery of the front section pipe 6, forming a cement-reinforced body 7. Simultaneously, inclined pile reinforcement piers 3 are cast using formwork, and the tops of the inclined steel pipe piles are firmly connected to the capping beam 2, forming a complete advanced support structure. After the concrete reaches the design strength, the excavation of the foundation pit can begin.
[0054] This embodiment, by adopting the above-mentioned sleeve joint structure, reduces the joint construction time of a single inclined steel pipe pile from the traditional 2 hours to 40 minutes, controls the coaxiality deviation of the joint within 2mm, and achieves a 100% first-pass yield rate for welds. It effectively solves the defects of the existing technology, significantly improves construction efficiency and the safety of the support structure, and achieves good engineering results.
[0055] The above embodiments are only for illustrating the technical concept and features of the present invention, and are intended to enable those skilled in the art to understand and implement the present invention. They should not be construed as limiting the scope of protection of the present invention. All equivalent changes or modifications made in accordance with the spirit and essence of the present invention should be covered within the scope of protection of the present invention.
Claims
1. An advanced support structure, characterized in that: It includes support piles (1), capping beams (2), inclined pile reinforcing piers (3), inclined piles and cement reinforcement bodies (7); the capping beams (2) are set on the top of the support piles (1), the inclined pile reinforcing piers (3) are fixedly connected to the capping beams (2), and the inclined piles are connected to the inclined pile reinforcing piers (3); The inclined pile includes a front section pipe (6), a rear section pipe (4), and a sleeve joint (5) for coaxial connection of the front section pipe (6) and the rear section pipe (4); the sleeve joint (5) includes a sleeve (9), a front section pipe sealing plate (10), a rear section pipe sealing plate (11), and several telescopic adjustment plates (12). The front pipe sealing plate (10) is welded and fixed to the sleeve (9) and the front pipe (6) respectively, and the rear pipe sealing plate (11) is welded and fixed to the sleeve (9) and the rear pipe (4) respectively; a plurality of the telescopic adjustment plates (12) are fixedly arranged inside the sleeve (9) and evenly distributed along the circumference of the sleeve (9). The telescopic adjustment plates (12) are used to apply a force to the rear pipe (4) in the direction of the central axis of the sleeve (9).
2. The advanced support structure according to claim 1, characterized in that: The telescopic adjustment piece (12) is a triangular steel piece. One or both ends of the telescopic adjustment piece (12) are welded and fixed to the inner wall of the sleeve (9). The protruding part of the telescopic adjustment piece (12) faces the central axis of the sleeve (9).
3. The advanced support structure according to claim 1, characterized in that: The front section pipe (6) is equipped with spiral blades (8), and the cement solidified body (7) is poured into the soil inside and outside the front section pipe (6).
4. The advanced support structure according to claim 1, characterized in that: The number of the telescopic adjustment pieces (12) is 3-6.
5. The advanced support structure according to claim 1, characterized in that: The front pipe sealing plate and the rear pipe sealing plate (11) are respectively connected at both ends of the sleeve (9).
6. The advanced support structure according to claim 1, characterized in that: Both the front pipe sealing plate (10) and the rear pipe sealing plate (11) are annular sealing plates.
7. The advanced support structure according to claim 6, characterized in that: The rear pipe sealing plate (11) consists of two semi-circular sealing plates.
8. A construction method for an advanced support structure, applied to the advanced support structure described in any one of claims 1-7, characterized in that: Includes the following steps: S1: The front section pipe sealing plate (10) is welded to the front section pipe (6) and the sleeve (9) respectively, and multiple telescopic adjustment plates (12) are uniformly welded to the inner wall of the sleeve (9) to obtain the front section pipe assembly; S2: The front section pipe assembly is pressed obliquely into the soil until the front section pipe (6) reaches the set depth; S3: Insert the lower end of the rear connector (4) into the sleeve (9), and use the multiple telescopic adjustment pieces (12) inside the sleeve (9) to automatically adjust the axis of the rear connector (4) to coincide with the axis of the front pipe (6) to achieve coaxial connection. S4: Weld the rear pipe sealing plate (11) to the rear pipe (4) and the sleeve (9) respectively to form an integral inclined pile structure; S5: Continue the inclined static pressure after connecting the pipe (4) until the entire inclined steel pipe pile reaches the design elevation; S6: Pour cement reinforcement (7) inside and around the front section pipe (6), and at the same time pour inclined pile reinforcement pier (3) so that the inclined steel pipe pile is connected to the top beam (2) and support pile (1) as a whole through the inclined pile reinforcement pier (3) to complete the construction of the advanced support structure.
9. The construction method for advanced support structure according to claim 8, characterized in that: In step S4, two semi-circular sealing plates are fitted onto the outside of the rear pipe (4) and spliced together to form the rear pipe sealing plate (11).
10. The construction method for advanced support structure according to claim 8 or 9, characterized in that: The inner ring of the front pipe sealing plate (10) is welded to the front pipe (6), and the outer ring is welded to the sleeve (9). The inner ring of the rear pipe sealing plate (11) is welded to the rear pipe (4), and the outer ring is welded to the sleeve (9).