Reinforcing structure of deep foundation pit support structure

Abstract

The utility model discloses a reinforcing structure of a deep foundation pit support structure. The reinforcing structure comprises two rows of evenly-distributed support piles inserted into a stratum, a steel plate concrete wall tightly attached to the pile faces, anchor rods tied to the upper portion of the steel plate concrete wall, an I-shaped steel transverse support embedded below the bottom face of a foundation pit and a support steel plate. The lower portion of the steel plate concrete wall serves as a bearing face of the I-shaped steel longitudinal beam, the I-shaped steel transverse support is supported on the I-shaped steel longitudinal beam, the I-shaped steel longitudinal beam and the I-shaped steel transverse support are each formed by two 22a I-shaped steel in a double-splicing mode, the pre-applied axial force of the I-shaped steel transverse support is 100 KN, the two sides of the I-shaped steel transverse support are 50 KN respectively, the axial force is applied at a constant speed, the load is kept for 2 min after the designed axial force is achieved, and the load is kept for 2 min. And then a steel wedge is vertically driven into the movable end (the side where axial force is pre-applied) to lock the steel support, then the jack is unloaded and dismantled, axial force is sequentially applied to other I-shaped steel transverse supports, finally, C30 concrete is poured in time for encapsulating the steel support, and the purpose of improving the strength of the foundation pit support structure is achieved.

Description

Technical Field

[0001] The utility model relates to the technical field of reinforcement structures, in particular to a reinforcement structure of a deep foundation pit enclosure structure. Background Art

[0002] Deep foundation pit retaining structures are support structures installed during deep foundation pit excavation to prevent soil collapse and protect surrounding buildings and roads. The design and construction of deep foundation pit retaining structures are crucial to ensuring the safety and stability of the foundation pit.

[0003] The selection and design of deep foundation pit retaining structures should be determined based on the specific project conditions, geological conditions, and surrounding environment. A reasonable deep foundation pit retaining structure can ensure safety during excavation, protect the stability of surrounding buildings and roads, and provide the necessary guarantees for subsequent foundation pit support and construction.

[0004] During the construction of deep foundation pit projects, retaining structures are required to support the foundation pit. Due to certain errors, the pile rows of the retaining structures of deep foundation pit projects have insufficient structural strength, so they need to be improved. Utility Model Content

[0005] The purpose of the utility model is to provide a reinforcement structure for a deep foundation pit retaining structure, which solves the problem of insufficient structural strength of the retaining structure of the deep foundation pit project due to certain errors in the pile rows.

[0006] To achieve the above-mentioned purpose, the utility model provides the following technical solutions: a reinforcement structure of a deep foundation pit retaining structure, comprising two rows of evenly distributed retaining piles inserted in the stratum, a steel plate concrete wall close to the pile surface, anchor rods for tying the upper part of the steel plate concrete wall, I-beam transverse supports embedded below the bottom surface of the foundation pit, and support steel plates, the retaining piles are inserted into the bottom surface of the foundation pit, and the outer sides of the retaining piles on the side that needs to be reinforced are in contact with the support steel plates, the lower outer sides of the support steel plates are fixedly connected to the I-beam longitudinal beam and the I-beam transverse supports, the outer sides of the I-beam transverse supports are encapsulated with concrete, and the I-beam transverse supports are supported on the retaining piles on the other side through the support steel plates, the upper part of the support steel plates is provided with tie anchor rods, the end heads of the anchor rods are connected with adaptive nuts, the nuts are in contact with the steel support steel plates, and the sides of the I-beam transverse supports are provided with a group of symmetrical steel shoes, and the steel shoes are provided with two symmetrical jacks on the left and right.

[0007] Preferably, an anchor hole is provided in the middle of the retaining pile, an anchor rod is provided inside the anchor hole, and the anchor rod is anchored to the stratum through 1:1 cement slurry.

[0008] Preferably, fine stone concrete is filled between the retaining piles and the supporting steel plates, and a steel plate concrete wall can be formed after the fine stone concrete is filled between the supporting steel plates. By filling the fine stone concrete, the structure of the connection between the retaining piles and the supporting steel plates can be strengthened.

[0009] Preferably, a steel wedge is provided on the I-beam transverse support, and the steel wedge is in close contact with the I-beam longitudinal beam. By designing the steel wedge, the I-beam transverse support and the I-beam longitudinal beam structure can be locked.

[0010] Preferably, the I-beam longitudinal beam and I-beam transverse support are both made of two 22a I-beams, and the I-beam transverse support has a preloaded axial force of 100 kN. By designing the I-beam transverse support and preloading it, two rows of retaining piles can be supported, achieving the purpose of reinforcement.

[0011] Preferably, the support steel plate is welded to the I-beam transverse support, and a stiffening rib is fixedly connected to the support steel plate, and the stiffening rib is welded to the I-beam transverse support and the support steel plate respectively. By designing the stiffening rib, deformation of the support steel plate can be prevented during the force transmission process of the support steel plate.

[0012] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0013] This utility model uses steel plate concrete walls to reinforce the pile surface and spaces between piles. The upper portion of the steel plate concrete wall uses PSB830-grade Ø25 finely rolled threaded steel as anchors to the ground, and the steel plates are filled with C20 fine aggregate concrete. The lower portion of the steel plate concrete wall serves as the support surface for the I-beam longitudinal beams, which are supported by the I-beam transverse supports. Both the I-beam longitudinal beams and the I-beam transverse supports are constructed from two 22a I-beams. The I-beam transverse supports are preloaded with an axial force of 100 kN, 50 kN on each side. The axial force is applied uniformly. After reaching the designed axial force, the load is held for 2 minutes. A steel wedge is then driven vertically into the active end (the preloaded end) to lock the steel support. The load is then unloaded and the jack removed. Axial force is then applied to the remaining I-beam transverse supports in sequence. Finally, C30 concrete is poured to encase the steel supports, enhancing the strength of the foundation pit retaining structure. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is a schematic diagram of the overall structure of the utility model;

[0015] Figure 2 For this utility model Figure 1 AA section view;

[0016] Figure 3 For this utility model Figure 2 Detailed drawings of nodes C and D;

[0017] Figure 4 For this utility model Figure 2 BB cross-sectional view.

[0018] In the figure: 1. Stratum; 2. Retaining piles; 3. I-beam longitudinal beam; 4. I-beam transverse support; 5. Anchor hole; 6. Nut; 7. Anchor; 8. Support steel plate; 10. Steel boot; 11. Jack; 12. Fine stone concrete; 13. Concrete; 14. Support steel plate; 15. Foundation pit bottom; 16. Steel wedge; 17. Stiffening rib. DETAILED DESCRIPTION

[0019] 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 embodiments described 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 making creative efforts are within the scope of protection of the present invention.

[0020] See also Figure 1 、 Figure 2 、 Figure 3 、 Figure 4 A reinforcement structure of a deep foundation pit retaining structure, comprising two rows of evenly distributed retaining piles 2 inserted into the stratum 1, steel plates 14 and fine stone concrete 12 close to the retaining piles 2, I-beam longitudinal beams 3 embedded below the bottom surface 15 of the foundation pit, I-beam transverse supports 4, and support steel plates 8. The retaining piles 2 are inserted into the bottom surface 15 of the foundation pit, and the outer sides of the retaining piles 2 on the side that needs to be reinforced are in contact with the supporting steel plates 14. The lower outer sides of the supporting steel plates 14 are fixedly connected with the I-beam longitudinal beams 3 and the I-beam transverse supports 4. The I-beam longitudinal beams 3 and the I-beam transverse supports 4 are both composed of two 22a I-beams. The pre-loaded axial force of the I-beam transverse supports is 100KN. By designing the I-beam transverse supports 4, the two rows of retaining piles 2 can be supported to achieve the purpose of reinforcement.

[0021] See also Figure 1 、 Figure 2 、 Figure 3 、 Figure 4 The outer side of the I-beam transverse support 4 is encapsulated with concrete 13, and the I-beam transverse support 4 is supported on the retaining pile 2 on the other side through the support steel plate 8. A tie anchor 7 is provided on the upper part of the support steel plate 14, and the end of the anchor 7 is connected with an adaptive nut 6. The nut 6 is in contact with the support steel plate 14. Fine stone concrete 12 is filled between the retaining pile 2 and the support steel plate 14. After the fine stone concrete 12 is filled between the support steel plates 14, a steel plate concrete wall can be formed. By filling the fine stone concrete 12, the structure of the connection between the retaining pile 2 and the support steel plate 14 can be strengthened. An anchor hole 5 is provided in the middle of the retaining pile 2, and an anchor 7 is provided inside the anchor hole 5. The anchor 7 is anchored to the stratum 1 through 1:1 cement slurry.

[0022] See also Figure 1 、 Figure 2 、 Figure 3 、 Figure 4 A group of symmetrical steel boots 10 are provided on the side of the I-beam transverse support 4, and two symmetrical jacks 11 are provided on the steel boots 10. A steel wedge 16 is provided on the I-beam transverse support 4, and the steel wedge 16 is in close contact with the I-beam longitudinal beam 3. By designing the steel wedge 16, the I-beam transverse support 4 and the I-beam longitudinal beam 3 structure can be locked. The support steel plate 8 is welded to the I-beam transverse support 4, and a stiffening rib 17 is fixedly connected to the support steel plate 8. The stiffening rib 17 is welded to the I-beam transverse support 4 and the support steel plate 8 respectively. By designing the stiffening rib 17, the force of the support steel plate 8 can be transmitted to prevent the deformation of the support steel plate 8.

[0023] The specific implementation process of the utility model is as follows: when in use, the support steel plate 14 is Q235A, 10mm thick, and the width and height are determined by the reinforcement range. The bottom is 300mm lower than the bottom of the I-beam horizontal steel support. The upper part uses PSB830 grade Ф25 finely rolled threaded steel as the anchor rod 7, the anchor rod hole diameter is 76mm, the anchor rod 7 length is 3.0m, and the leakage is 250mm. First, use 1:1 cement slurry to grout the anchor rod hole 5, and then insert the anchor rod 7. The strengthening time is not less than 7d. Note that the pipe mouth must be reasonably sealed to prevent the cement slurry from overflowing. After the strength of the anchor rod 7 anchoring cement slurry reaches the design requirements, the support steel plate 14 is installed. The support steel plate 14 is pre-drilled at the end of the leaking anchor rod 7, with a hole diameter of 30mm. After the anchor rod 7 passes through the support steel plate 14, it is firmly fixed with a finely rolled threaded steel adapter gasket and nut 6. Then pour the supporting steel plate 14 and fill it with fine stone concrete 12. Use C20 fine stone concrete, pour and vibrate the concrete layer by layer to make it dense. The pouring height of the fine stone concrete 12 should be flush with the upper edge of the supporting steel plate 14.

[0024] The I-beam transverse support 4 is constructed from two 22a I-beams spliced together, arc-welded. The seam is 200mm long and spaced 1m apart longitudinally. Square Q235A steel plates with a side length of 25cm and a thickness of 10mm are used at each end as supports. At the angle formed by the support steel plate 8 and the I-beam transverse support 4, isosceles right-angled triangle Q235A steel plates are used as stiffeners 17. These are 10mm thick and have a right-angle side length of 5cm. The fixed end is securely and closely attached to the surrounding structure. The movable end, i.e., the end for prestressing the axial force, is welded to the steel support to provide a prestressing support. The steel shoe 10 is made from 12.6 I-beams cut at a 45° angle, meaning it is also 12.6cm wide. The steel shoe 10 is fully welded to the I-beam transverse support 4. The I-beam transverse support 4 is pre-loaded with an axial force of 100KN, 50KN on each side. The front ends of two 10t jacks 11 are supported on the plane of the steel shoe 10, and the rear ends are supported on the I-beam longitudinal beam 3. The axial force is applied at a uniform speed. After reaching the designed axial force, the load is held for 2 minutes. After the pressure gauge reading stabilizes, a steel wedge 16 is vertically driven into the movable end to lock the steel support. The load is then unloaded and the jacks 11 are removed. Then, the axial force is applied to the other I-beam transverse supports in turn.

[0025] After the prestressing axial force is applied, the steel support encapsulating concrete 13 is poured in time to ensure the stability of the structure. The concrete 13 uses C30 concrete.

[0026] Although the embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and variations may be made to these embodiments without departing from the principles and spirit of the present invention, and the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A reinforcement structure for a deep foundation pit retaining structure, comprising two rows of retaining piles (2) evenly distributed and inserted into a stratum (1), steel plates (14) and fine stone concrete (12) closely attached to the retaining piles (2), I-beam longitudinal beams (3) embedded below the foundation pit bottom surface (15), I-beam transverse supports (4), and support steel plates (8), characterized in that: The retaining pile (2) is plugged into the bottom surface (15) of the foundation pit. The outer side of the retaining pile (2) on the side that needs to be reinforced is in contact with a supporting steel plate (14). An I-beam longitudinal beam (3) and an I-beam transverse support (4) are provided on the outer side of the lower part of the supporting steel plate (14). The outer side of the I-beam transverse support (4) is enclosed with concrete (13). The I-beam transverse support (4) is supported on the retaining pile (2) on the other side through a support steel plate (8). A tie anchor rod (7) is provided on the upper part of the supporting steel plate (14). The end of the anchor rod (7) is connected with an adapted nut (6). The nut (6) contacts the supporting steel plate (14). A group of symmetrical steel boots (10) are provided on the side of the I-beam transverse support (4). Two jacks (11) are provided on the steel boots (10) that are symmetrical on the left and right.

2. The reinforcement structure of the deep foundation pit retaining structure according to claim 1, characterized in that: An anchor hole (5) is provided in the middle of the retaining pile (2), an anchor rod (7) is provided inside the anchor hole (5), and the anchor rod (7) is anchored to the stratum (1) through 1:1 cement slurry.

3. The reinforcement structure of a deep foundation pit retaining structure according to claim 1, characterized in that: Fine stone concrete (12) is filled between the retaining piles (2) and the supporting steel plates (14), and a steel plate concrete wall can be formed after the fine stone concrete (12) is filled between the supporting steel plates (14).

4. The reinforcement structure of the deep foundation pit retaining structure according to claim 1, characterized in that: A steel wedge (16) is provided at the end of the I-beam transverse support (4), and the steel wedge (16) is in close contact with the I-beam longitudinal beam (3).

5. The reinforcement structure of the deep foundation pit retaining structure according to claim 1, characterized in that: The I-steel longitudinal beam (3) and the I-steel transverse support (4) are both formed by splicing two 22a I-steels together, the transverse support pre-loaded axial force is 100KN, and the I-steel longitudinal beam (3) is formed by splicing two 22a I-steels together.

6. The reinforcement structure of the deep foundation pit retaining structure according to claim 1, characterized in that: The support steel plate (8) is welded to the I-steel transverse support (4), and a stiffening rib (17) is fixedly connected to the support steel plate (8), and the stiffening rib (17) is welded to the I-steel transverse support (4) and the support steel plate (8), respectively.

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