Prestressed concrete pipe pile straining beam structure suitable for soft soil roadbed treatment

Abstract

The utility model provides a prestressed concrete pipe pile straining beam structure suitable for soft soil roadbed treatment, which comprises a plurality of pipe piles vertically pre-buried in a soft soil foundation, the top of each pipe pile is provided with a pile cap, the plurality of pipe piles are equidistantly arranged front and back as well as left and right and form a square on the horizontal plane, and straining beams are connected between the adjacent pile caps; the straining beam is arranged in a shape like a Chinese character'tian ', and four vertexes of the straining beam are connected with the pipe piles and the pile caps of the pipe piles respectively. The straining beam for connecting the tops of the tubular piles and the pile caps is arranged to be in the shape of the Chinese character'tian ', the reinforcing parts are additionally arranged between the original connecting parts, the integrity and the structural strength of the straining beam are improved, the pile distance between the tubular piles can be properly increased under the condition that the structural strength is guaranteed, the number of the tubular piles is reduced, and the problem that the manufacturing cost is high due to the fact that the tubular piles are dense is solved.

Description

Technical Field

[0001] The utility model relates to the technical field of geotechnical engineering, in particular to a prestressed concrete pipe pile tie beam structure suitable for soft soil subgrade treatment. Background Technique

[0002] Soft soil foundations are mainly composed of soils with high water content, fine particles, loose structures, and imperfect development, such as clay, silt, organic soil, and peat. Such foundations often bring a series of challenges in engineering construction, including problems such as foundation instability, settlement, and liquefaction, posing a serious threat to the safety and stability of projects such as highways, bridges, and buildings. Therefore, strengthening the structural treatment of soft soil foundations has become the key to ensuring project quality and safety.

[0003] Chinese Patent CN217204023U discloses a steel section steel pipe pile grid beam foundation reinforcement structure, including a number of pipe piles arranged in a pre-treated soft soil foundation. The pipe piles are all steel sections, the pipe piles are all arranged in the gravity direction and are distributed in a matrix pattern. Pile caps are installed on the tops of all the pipe piles. A tie beam connection structure is connected between a number of longitudinally and transversely adjacent pile caps. A cushion layer is provided above all the pile caps and the tie beam connection structure. The cushion layer includes a gravel cushion layer and high-strength steel wire grids laid on the top and bottom surfaces of the gravel cushion layer. The utility model forms an integral structure through the provided pipe pile reinforcement structure, pile caps, and tie beam connection structure, and has the advantages of being able to withstand large loads of the subgrade, having a strong structure, convenient construction, and short construction period, and having the ability to quickly reinforce soft foundations under poor construction site conditions or in emergency rescue situations, while ensuring the reinforcement quality of soft foundations.

[0004] However, the following problems exist in this technical solution. First, its tie beam is connected to the pile cap in a "mouth" shape, and the structural form is relatively single, only arranged between longitudinally and transversely adjacent pile caps. In order to ensure the reinforcement effect, the pipe piles need to be arranged densely, the spacing adjustment range is small, and the cost is high. Second, the directions of the pile caps and the internal steel bars in them are the same as those of the tie beam, and they are all quadrilateral, without forming a stable structure. Content of the Utility Model

[0005] The purpose of the utility model is to provide a prestressed concrete pipe pile tie beam structure suitable for soft soil subgrade treatment in view of the deficiencies of the prior art. By setting the tie beam connecting the tops of each pipe pile and the pile cap in a "field" shape and adding a strengthening part between the original connecting parts, the integrity and structural strength of the tie beam are improved, and the pile spacing of the pipe piles can be appropriately increased while ensuring the structural strength, reducing the number of pipe piles, and solving the problem of high cost caused by dense pipe piles.

[0006] To achieve the above purpose, the utility model provides the following technical solutions:

[0007] Prestressed concrete pipe pile tie beam structure suitable for soft soil subgrade treatment, including several pipe piles vertically embedded in the soft soil subgrade. Pile caps are installed on the tops of all the pipe piles. The several pipe piles are equidistant from front to back and left to right, and are arranged in a square on the horizontal plane. A tie beam is connected between adjacent pile caps;

[0008] The tie beam is arranged in a "field" shape, and its four vertices are respectively connected to the pipe piles and their pile caps.

[0009] As an option, the tie beam includes a connecting part connected to the pipe pile and the pile cap, and a strengthening part with both ends connected to the midpoints of the connecting part.

[0010] As an option, the tie beam includes several main reinforcement bars arranged along its length direction and stirrups tightly wound around the main reinforcement bars along the width direction.

[0011] As an option, the stirrups are connected end to end to form a rectangle. The main reinforcement bars are arranged in two parallel rows up and down, and are at least arranged inside the four vertices of the stirrups.

[0012] As an option, the outer contour of the pile cap is square, and a steel bar mesh is arranged inside it. The steel bar mesh is a square grid. The included angle between the pile cap and the steel bar mesh and the tie beam and the main reinforcement bar is 45°.

[0013] As an option, a geogrid is laid on the tops of the pile cap and the tie beam, and at least one layer of geogrid is provided.

[0014] As an option, each layer of geogrid includes a cushion layer and a steel-plastic geogrid laid on the cushion layer.

[0015] As an option, the outer diameter of the pipe pile is 300 - 500 mm, and the wall thickness is 60 - 100 mm.

[0016] As an option, the side length of the pile cap is 800 - 1200 mm, and the width of the tie beam is 400 - 600 mm.

[0017] As an option, the pile cap and the tie beam are made by cast-in-place concrete, and the thickness is 300 - 400 mm.

[0018] The beneficial effects of the present utility model are as follows:

[0019] (1) By changing the tie beam connecting the tops of each pipe pile and the pile cap from the original "square" shape to a "field" shape, the present utility model optimizes the connection method and size of the tie beam, forms a reticular reinforcement layer on the top of the pipe pile. Therefore, the pile spacing of the pipe pile can be appropriately increased while ensuring the structural strength, the number of pipe piles can be reduced, and the construction cost can be saved.

[0020] (2) By adopting the design of the connecting part and the strengthening part in the tie beam, the utility model not only ensures the stable connection with the pipe pile and the pile cap, but also enhances the bending resistance of the tie beam through the strengthening part, improving the integrity and structural strength of the tie beam.

[0021] (3) By arranging a steel bar mesh in the pile cap, and the steel bar mesh and the main steel bars cross to form a stable triangular structure, and the steel bar mesh, the main steel bars and the stirrups are connected by welding, the mechanical properties and durability of the tie beam are further improved.

[0022] (4) By laying two layers of geogrids, especially by adopting the combination of the cushion layer and the steel-plastic geogrid, not only the shear strength and stability of the foundation surface layer are improved, but also the drainage consolidation of the foundation soil mass is promoted, which helps to further control the foundation settlement.

[0023] In summary, the utility model has the advantages of cost saving, high structural strength, strong stability, etc., increasing the integrity of the pipe pile group, the pile cap and the tie beam, being beneficial to ensuring the project quality and reducing the project risk. Brief Description of the Drawings

[0024] Figure 1 It is a top view structural schematic diagram of the utility model;

[0025] Figure 2 It is a cross-sectional schematic diagram of the tie beam of the utility model;

[0026] Figure 3 It is a schematic diagram of the top layer steel bar structure of the pile cap of the utility model;

[0027] Figure 4 It is a longitudinal section structural schematic diagram of the road section of the utility model. Detailed Embodiment

[0028] Next, the technical solutions in the embodiments of the utility model will be clearly and completely described in conjunction with the drawings in the embodiments of the utility model. Obviously, the described embodiments are only a part of the embodiments of the utility model, rather than all the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the utility model.

[0029] In the description of the present utility model, it should be understood that the orientation or positional relationship indicated by the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", etc. is based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the present utility model and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, it should not be construed as a limitation to the present utility model. In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include one or more of such features. In the description of the present utility model, the meaning of "a plurality" is two or more, unless otherwise specifically defined.

[0030] Embodiment 1

[0031] As Figures 1-4 shown, this embodiment provides a prestressed concrete pipe pile tie beam structure suitable for soft soil subgrade treatment, including several pipe piles 1 vertically embedded in the soft soil foundation. The top of each pipe pile 1 is provided with a pile cap 2. The several pipe piles 1 are equidistant front and back and left and right, and are arranged in a square on the horizontal plane. A tie beam 3 is connected between adjacent pile caps 2; the tie beam 3 is arranged in a "field" shape, and its four vertices are respectively connected to the pipe pile 1 and its pile cap 2.

[0032] By changing the tie beam 3 connecting the tops of the pipe piles 1 and the pile caps 2 from the original "square" shape to a "field" shape, the connection method and size of the tie beam 3 are optimized, and a reticulated reinforcement layer is formed on the top of the pipe piles 1. Therefore, the pile spacing of the pipe piles 1 can be appropriately increased while ensuring the structural strength, the number of pipe piles 1 can be reduced, and the construction cost can be saved.

[0033] As Figure 1 shown, the tie beam 3 includes a connecting portion 31 connected to the pipe pile 1 and the pile cap 2, and a strengthening portion 32 with both ends connected to the midpoint of the connecting portion 31.

[0034] By adopting the design of the connecting portion 31 and the strengthening portion 32 in the tie beam 3, not only the stable connection with the pipe pile 1 and the pile cap 2 is ensured, but also the bending resistance of the tie beam 1 is enhanced by the strengthening portion 32, and the integrity and structural strength of the tie beam 3 are improved.

[0035] As Figure 2As shown in the figure, the tie beam 3 includes a number of main reinforcement bars 33 arranged along its length direction and stirrups 34 tightly surrounding the main reinforcement bars 33 along the width direction. The stirrups 34 are joined end to end to form a rectangle. The main reinforcement bars 33 are arranged in two parallel rows, top and bottom, and are at least arranged inside the four vertices of the stirrups 34. In this embodiment, there are four main reinforcement bars on each of the upper and lower sides of the main reinforcement bars 33, and the spacing between the two middle ones is slightly larger than the spacing at the edges, so that the tie beam 33 has better bending resistance performance.

[0036] As Figure 1 , 3 shown in the figure, the outer contour of the pile cap 2 is square, and a steel bar mesh 21 is arranged inside it. The steel bar mesh 21 is a square grid. The included angle between the pile cap 2 and the steel bar mesh 21 and the tie beam 3 and the main reinforcement bars 33 is 45°. The steel bar mesh 21 and the main reinforcement bars 33 cross to form a triangle, and the structure is stable. In this embodiment, the steel bar mesh 21 is provided with two upper and lower layers corresponding to the main reinforcement bars 33, and the grid of the steel bar mesh 21 in the upper layer is denser. The steel bar mesh 21, the main reinforcement bars 33 and the stirrups 34 are connected by welding.

[0037] By arranging the steel bar mesh 21 on the pile cap 2, and the steel bar mesh 21 and the main reinforcement bars 33 cross to form a stable triangular structure, and the steel bar mesh 21, the main reinforcement bars 33 and the stirrups 34 are connected by welding, the mechanical properties and durability of the tie beam 3 are further improved.

[0038] As Figures 1-3 shown in the figure, the outer diameter of the pipe pile 1 is 300 - 500 mm, the wall thickness is 60 - 100 mm, the side length of the pile cap 2 is 800 - 1200 mm, and the width of the tie beam 3 is 400 - 600 mm; the pile cap 2 and the tie beam 3 are made of cast-in-place concrete and are cast into a whole, with a thickness of 300 - 400 mm. It should be noted that when the tie beam 3 is in a "mouth" shape, the maximum distance between the pipe piles 1 is about 5 times the side length of the pile cap 2. After using the "field" - shaped tie beam 3 in this embodiment, the distance between the pipe piles 1 can be up to 8 times the side length of the pile cap 2.

[0039] This embodiment optimizes the stress condition of the pipe pile 1 pile group, increases the integrity of the pile group, is more conducive to the stability of the soft foundation after the treatment of the pipe piles 1. For the situation of uneven soft soil depth, relatively high subgrade filling height or large free face, it is more conducive to ensuring the project quality, reducing the project risk. At the same time, combined with the actual project, it also has a positive effect on shortening the construction period and saving investment.

[0040] Embodiment Two

[0041] As Figure 4As shown in the figure, the components that are the same or corresponding to those in the first embodiment are marked with the corresponding reference numerals in the first embodiment. For the sake of simplicity, only the differences from the first embodiment will be described below. The difference between the second embodiment and the first embodiment is as follows: In this second embodiment, a strengthening structure built on soft soil foundation is taken as an example. The pipe pile 1 is preset in the soft soil, and the pile caps 2 and the top surfaces of the tie beams 3 connecting the pile caps 2 are at the same horizontal plane. A geogrid 4 is laid on the tops of the pile caps 2 and the tie beams 3, and at least one layer of the geogrid 4 is provided. Each layer of the geogrid 4 includes a cushion layer 41 and a steel-plastic grid 42 laid on the cushion layer 41. In this embodiment, two layers of the geogrid 4 are provided, and the cushion layer 41 of the lower-layer geogrid 4 is 20 cm thick, and the cushion layer 41 of the upper-layer geogrid 4 is 50 cm thick.

[0042] By laying two layers of the geogrid 4, especially by adopting the combination of the cushion layer 41 and the steel-plastic grid 42, not only the shear strength and stability of the surface layer of the foundation are improved, but also the drainage consolidation of the foundation soil mass is promoted, which helps to further control the foundation settlement.

[0043] The above are only the preferred embodiments of the present invention, and are not intended to limit the present invention. Any modifications, equivalent replacements, and improvements made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A prestressed concrete pipe pile tie beam structure suitable for soft soil roadbed treatment, comprising a plurality of pipe piles vertically pre-buried in the soft soil foundation, characterized in that: Pile caps are installed at the tops of all the pipe piles. A number of the pipe piles are equidistant from each other in the front and back and left and right directions, and are arranged in a square on the horizontal plane. Connecting beams are connected between adjacent pile caps; The connecting beams are arranged in a "field" shape, and its four vertices are respectively connected to the pipe piles and their pile caps.

2. The prestressed concrete pipe pile tie beam structure suitable for soft soil roadbed treatment according to claim 1 is characterized in that: The connecting beam includes a connecting part connected to the pipe pile and the pile cap, and a strengthening part with both ends connected to the midpoints of the connecting part.

3. The prestressed concrete pipe pile tie beam structure suitable for soft soil roadbed treatment according to claim 1 is characterized in that: The connecting beam includes a number of main reinforcement bars arranged along its length direction and stirrups tightly wound around the main reinforcement bars along the width direction.

4. The prestressed concrete pipe pile tie beam structure suitable for soft soil roadbed treatment according to claim 3 is characterized in that: The stirrups are joined end to end to form a rectangle. The main reinforcement bars are arranged in two parallel rows up and down, and are at least arranged inside the four vertices of the stirrups.

5. The prestressed concrete pipe pile tie beam structure suitable for soft soil roadbed treatment according to claim 3 is characterized in that: The outer contour of the pile cap is square, and a steel bar mesh is arranged inside it. The steel bar mesh is a square grid. The included angle between the pile cap and the steel bar mesh and the connecting beam and the main reinforcement bar is 45°.

6. The prestressed concrete pipe pile tie beam structure suitable for soft soil roadbed treatment according to claim 1 is characterized in that: Geogrid is laid on the tops of the pile caps and the connecting beams, and at least one layer of geogrid is provided.

7. The prestressed concrete pipe pile tie beam structure suitable for soft soil roadbed treatment according to claim 6 is characterized in that: Each layer of the geogrid includes a cushion layer and a steel-plastic grid laid on the cushion layer.

8. The prestressed concrete pipe pile tie beam structure suitable for soft soil roadbed treatment according to claim 1 is characterized in that: The outer diameter of the pipe pile is 300 - 500 mm, and the wall thickness is 60 - 100 mm.

9. The prestressed concrete pipe pile tie beam structure suitable for soft soil roadbed treatment according to claim 5, characterized in that: The side length of the pile cap is 800 - 1200 mm, and the width of the connecting beam is 400 - 600 mm.

10. The prestressed concrete pipe pile tie beam structure suitable for soft soil roadbed treatment according to claim 1, characterized in that: The pile cap and the connecting beam are made by cast-in-place concrete, and the thickness is 300 - 400 mm.

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