Recoverable foundation pit retaining pile structure based on soft soil layer prestress

Abstract

The application discloses a recyclable foundation pit support pile structure based on soft soil layer prestress, which comprises multiple groups of support piles and steel sheet piles symmetrically arranged on both sides of the multiple groups of support piles, a reinforcing steel pipe is arranged in the support pile, a pressure roof beam is arranged above the two groups of steel sheet piles and the multiple groups of reinforcing steel pipes, four fixing grooves are formed in the upper portion of the pressure roof beam, two U-shaped plates are connected in the two transversely arranged fixing grooves, the bottom of the U-shaped plate extends to the lower portion of the pressure roof beam and is fixedly connected with an upper positioning plate, four limiting grooves are further formed in the upper portion of the pressure roof beam, a side steel plate is slidably arranged in the limiting groove, and the bottom of the side steel plate penetrates through the pressure roof beam and the upper positioning plate.

Description

Technical Field

[0001] This invention relates to the field of foundation pit excavation and support technology, and more specifically, to a recyclable foundation pit retaining pile structure based on prestressed soft soil. Background Technology

[0002] In traditional foundation pit support structures, horizontal bracing is often used, which means that horizontal support is set between two opposite pit walls. The construction of horizontal bracing is carried out simultaneously with earthwork excavation. During the excavation process, bracing is used as it is excavated to support the support structure on both sides, which can ensure the stability of the foundation pit. It is widely used in foundation pit support. However, horizontal bracing occupies the internal space of the foundation pit, restricts the movement of excavation equipment, and the construction speed of horizontal bracing is slow and the cycle is long, which affects the construction progress inside the foundation pit.

[0003] Later, steel sheet piles were used to limit the side walls of the foundation pit to speed up the construction progress inside the pit. However, as the foundation pit is dug deeper, the steel sheet piles are often deformed due to the fluidity of the soft soil layer and the fluidity of groundwater, and they bulge to one side of the foundation pit, posing a risk of collapse. It is not possible to use the foundation pit retaining pile structure to press and limit the upper part of the foundation pit, the middle mesh-type limit, and the bottom insertion limit to prevent the steel sheet piles on the side of the foundation pit from deforming, improve their deformation resistance, and reduce the risk of foundation pit collapse.

[0004] Furthermore, it is impossible to recycle the structure on the retaining piles after the foundation pit excavation is completed. Therefore, a solution is provided. Summary of the Invention

[0005] In order to overcome the above-mentioned defects of the prior art, the present invention provides a recyclable foundation pit retaining pile structure based on soft soil prestressing.

[0006] To achieve the above objectives, the present invention provides the following technical solution: a recyclable foundation pit retaining pile structure based on soft soil prestressing, comprising multiple sets of retaining piles and steel sheet piles symmetrically arranged on both sides of the multiple sets of retaining piles. Reinforcing steel pipes are inserted inside the retaining piles. A capping beam is provided above the two sets of steel sheet piles and the multiple sets of reinforcing steel pipes. Four fixing slots are provided above the capping beam. Two horizontally arranged fixing slots are connected to U-shaped plates. The bottom of the U-shaped plates extends to the capping beam and is fixedly connected to an upper positioning plate.

[0007] Four limiting grooves are also provided above the capping beam. Side steel plates are slidably arranged inside the limiting grooves. The bottom of the side steel plates passes through the capping beam and the upper positioning plate. The bottom of the two side steel plates arranged horizontally are connected to the lower positioning plate. The upper positioning plate and the lower positioning plate are both fitted to the outer wall of the sheet pile.

[0008] Furthermore, the two U-shaped plates are connected by a bidirectional threaded rod, and both sides of the bidirectional threaded rod are rotatably connected to the pressure beam through mounting plates. The end of the bidirectional threaded rod is provided with a handle.

[0009] Furthermore, the lower positioning plate is symmetrically provided with two mounting grooves on the side wall near the sheet pile. A movable roller is rotatably installed inside the mounting groove. The movable roller is in transmission cooperation with the side wall of the sheet pile. The upper positioning plate is fixedly connected to the side steel plate by a fixed threaded rod.

[0010] Furthermore, multiple sets of arrayed connection holes are provided on the opposite side walls of the side steel plates, and a connector is provided between two connection holes located on the same horizontal line.

[0011] Furthermore, the connector includes a first connecting steel column, a second connecting steel column, and a third connecting steel column. The first connecting steel column and the second connecting steel column are slidably fitted at one end, and the other end of the second connecting steel column is fixedly connected to the third connecting steel column. Both the first connecting steel column and the second connecting steel column are threadedly connected to their corresponding connecting holes.

[0012] Furthermore, multiple pairs of protruding plates are fixedly installed on the side wall of the lower positioning plate away from the sheet pile, and a limit shaft is fixedly installed between a pair of protruding plates.

[0013] Furthermore, a support plate is fixedly provided on the outer side of the limiting shaft, a positioning rod is vertically threadedly connected to the upper part of the support plate, and a handle is fixedly provided on the upper part of the positioning rod.

[0014] The reinforcement steps for the steel sheet piles in this foundation pit retaining pile structure are as follows:

[0015] Top pressing reinforcement: Control the rotation of the bidirectional threaded rod so that the two U-shaped plates drive the upper positioning plate to press tightly against the side wall of the steel sheet pile, and press and limit the top of the steel sheet pile;

[0016] Central mesh reinforcement: Control the rotation of the fixed threaded rod, move the side steel plate downward to the designated position, and then fix the side steel plate by the fixed threaded rod. Connect the end of the connecting steel column 2 and the end of the connecting steel column 1 to the corresponding connecting holes respectively. A mesh-like limit is formed on the side wall of the foundation pit by multiple sets of horizontally arranged connectors and the longitudinally arranged side steel plates.

[0017] Bottom insertion reinforcement: After the side steel plate moves downward to the designated position, align the positioning rod on the lower positioning plate with the upper surface of the pit, and then turn the control handle to insert the positioning rod into the upper surface of the pit to reinforce and stabilize the position of the lower positioning plate.

[0018] The technical effects and advantages of this invention are as follows:

[0019] 1. This invention controls the rotation of a bidirectional threaded rod, causing two U-shaped plates to drive the upper positioning plate to press against the side wall of the sheet pile, thus limiting the upper part of the sheet pile. The fixed threaded rod is then rotated to move the side steel plate downwards to a designated position, where it is then fixed by the threaded rod. The ends of connecting steel column two and connecting steel column one are connected to their corresponding connecting holes. Multiple sets of horizontally arranged connectors and the longitudinally arranged side steel plates form a mesh-like limiting system for the pit sidewall. After the side steel plate moves downwards to the designated position, the positioning rod on the lower positioning plate is aligned with the upper surface of the pit, and the handle is rotated to insert the positioning rod into the upper surface of the pit, reinforcing and stabilizing the position of the lower positioning plate. This device, through upper pressing and limiting, middle mesh-like limiting, and bottom insertion limiting of the pit, prevents deformation of the sheet piles on the pit side, improves their deformation resistance, and reduces the risk of pit collapse.

[0020] 2. This invention removes the lower positioning plate from above the side steel plate by loosening the bolts on the upper positioning plate, and then removes the side steel plate by loosening the fixing threaded rod. The upper positioning plate is then disassembled by loosening the bolts connecting the upper positioning plate and the U-shaped plate. Simultaneously, the positioning rod can be disassembled when the lower positioning plate is recycled, allowing for the recycling of the structure on the retaining pile and improving resource utilization. Attached Figure Description

[0021] Figure 1 This is a view of the overall structure of the foundation pit after it has been dug in this invention.

[0022] Figure 2 This is a perspective view of the overall structure of the enclosure component in this invention.

[0023] Figure 3 This is the overall structural appearance of the foundation pit when it is first excavated in this invention.

[0024] Figure 4 This is a three-dimensional view of the overall structure of the enclosure component at its initial position in this invention.

[0025] Figure 5 This is a three-dimensional view of the structure above the pressure beam in this invention.

[0026] Figure 6 This is a perspective view of the lower positioning plate and the moving roller in this invention.

[0027] Figure 7 This is a perspective view of the connector in this invention.

[0028] Figure 8 This is a three-dimensional view of the overall structure of the positioning component in this invention.

[0029] The attached diagram is labeled as follows: 1. Support pile; 2. Sheet pile; 3. Reinforcing steel pipe; 4. Top beam; 5. Fixing groove; 6. U-shaped plate; 7. Two-way threaded rod; 8. Lower positioning plate; 9. Side steel plate; 10. Fixing threaded rod; 11. Connecting hole; 12. Upper positioning plate; 13. Moving roller; 14. Connecting steel column one; 15. Connecting steel column three; 16. Support plate; 17. Protruding plate; 18. Limiting shaft; 19. Positioning rod; 20. Handle one; 21. Handle two; 22. Connecting steel column two. Detailed Implementation

[0030] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0031] Example 1: Please refer to Figures 1-8 As shown, the steel sheet pile 2 will deform and bulge to one side of the foundation pit as the foundation pit is dug deeper and deeper, which can be solved by the following solution.

[0032] In this embodiment, a recyclable foundation pit retaining pile structure based on soft soil prestressing includes multiple sets of support piles 1 and steel sheet piles 2 symmetrically arranged on both sides of the multiple sets of support piles 1. Reinforcing steel pipes 3 are inserted inside the support piles 1. A capping beam 4 is set above the two sets of steel sheet piles 2 and the multiple sets of reinforcing steel pipes 3. Four fixing slots 5 are opened above the capping beam 4. Two horizontally arranged fixing slots 5 are connected to U-shaped plates 6. The bottom of the U-shaped plates 6 extends to the capping beam 4 and is fixedly connected to an upper positioning plate 12.

[0033] It needs to be explained here that: before the foundation pit is excavated, cement soil support piles 1 are constructed at a certain distance back from the edge of the foundation pit. During this period, in order to enhance the shear resistance, bending resistance and deformation resistance of the support piles 1, reinforcing steel pipes 3 are vertically inserted into the interior of the support piles 1. At the same time, a certain length of the top of the reinforcing steel pipes 3 is reserved to protrude outside the support piles 1, and there are two rows.

[0034] Please see Figures 1-5 As shown, the two U-shaped plates 6 are connected by a bidirectional threaded rod 7, and both sides of the bidirectional threaded rod 7 are rotatably connected to the top beam 4 through mounting plates. The end of the bidirectional threaded rod 7 is provided with a handle 21.

[0035] It needs to be explained here that: when the bidirectional threaded rod 7 is rotated, the two U-shaped plates 6 are limited by the fixing groove 5 and move closer to each other until the two U-shaped plates 6 drive the upper positioning plate 12 to stick tightly to the side wall of the steel sheet pile 2, and initially limit the upper part of the steel sheet pile 2.

[0036] Meanwhile, when the sheet pile 2 is installed into the slot, the position of the sheet pile 2 is higher than the top of the support pile 1 and lower than the top of the reinforcing steel pipe 3;

[0037] When the capping beam 4 is installed, the bottom of the capping beam 4 is made to contact the top of the sheet pile 2, and the capping beam 4 passes through the top of multiple reinforcing steel pipes 3 to limit the capping beam 4 and ensure the stability of the capping beam 4 during installation.

[0038] Please see Figures 1-5 and Figure 6 As shown, four limiting grooves are also provided above the capping beam 4. Side steel plates 9 are slidably arranged inside the limiting grooves. The bottom of the side steel plates 9 passes through the capping beam 4 and the upper positioning plate 12. The bottom of the two side steel plates 9 arranged horizontally are connected to the lower positioning plate 8. The upper positioning plate 12 and the lower positioning plate 8 are both fitted to the outer wall of the steel sheet pile 2.

[0039] The two U-shaped plates 6 move closer to each other, causing the upper positioning plate 12, the side steel plate 9, and the lower positioning plate 8 to simultaneously adhere to the outer wall of the sheet pile 2. The two side steel plates 9 on the same side limit the longitudinal movement of the sheet pile 2.

[0040] Please see Figures 1-5 and Figure 6 As shown, two mounting slots are symmetrically provided on the side wall of the lower positioning plate 8 near the steel sheet pile 2. A movable roller 13 is rotatably installed inside the mounting slot. The movable roller 13 is in transmission cooperation with the side wall of the steel sheet pile 2. The upper positioning plate and the side steel plate 9 are fixedly connected by a fixed threaded rod 10.

[0041] According to the depth of the foundation pit, adjust the downward movement distance of the side steel plate 9, that is, the bottom of the lower positioning plate 8 is 20cm-50cm away from the upper surface of the foundation pit. After adjusting the position of the side steel plate 9, fix the side steel plate 9 by fixing the threaded rod 10. Then, install the connector horizontally inside the corresponding connecting hole 11 to limit the steel sheet pile 2 laterally. Together with the longitudinal limit of the side steel plate 9, a mesh-like limit fixation is formed in the middle of the steel sheet pile 2 to prevent the steel sheet pile 2 from deforming.

[0042] Please see Figures 1-5 and Figure 6 As shown, multiple sets of arrayed connecting holes 11 are provided on the opposite side walls of the side steel plate 9, and a connector is provided between two connecting holes 11 located on the same horizontal line.

[0043] Please see Figures 1-2 and Figure 7 As shown, the connector includes a first connecting steel column 14, a second connecting steel column 22, and a third connecting steel column 15. One end of the first connecting steel column 14 is slidably fitted with one end of the second connecting steel column 22, and the other end of the second connecting steel column 22 is fixedly connected to the third connecting steel column 15. Both the first connecting steel column 14 and the second connecting steel column 22 are threadedly connected to their corresponding connecting holes 11.

[0044] Please see Figures 1-2 and Figure 8 As shown, multiple pairs of protruding plates 17 are fixedly installed on the side wall of the lower positioning plate 8 away from the sheet pile 2. A limiting shaft 18 is fixedly installed between a pair of protruding plates 17. A support plate 16 is fixedly installed on the outside of the limiting shaft 18. A positioning rod 19 is vertically threadedly connected to the upper part of the support plate 16. A handle 20 is fixedly installed above the positioning rod 19. When the positioning rod 19 on the lower positioning plate 8 is aligned with the upper surface of the pit, the handle 20 is rotated to insert the positioning rod 19 into the upper surface of the pit, further reinforcing the position of the lower positioning plate 8.

[0045] In this embodiment, the steel sheet piles 2 on the side of the foundation pit are prevented from deforming by pressing and limiting the upper part of the foundation pit, the middle mesh-type limiting part, and the bottom insertion limiting part, thereby improving their deformation resistance and reducing the risk of foundation pit collapse.

[0046] Example 2 addresses the problem that the structure on the retaining piles cannot be recycled after the foundation pit excavation is completed;

[0047] In this embodiment, after the excavation of the foundation pit is completed, the bolts above the lower positioning plate 8 are loosened, and the lower positioning plate 8 is removed from the top of the side steel plate 9. After the threaded rod 10 is loosened, the side steel plate 9 is removed. The bolts at the connection between the upper positioning plate 12 and the U-shaped plate 6 are loosened, and the upper positioning plate 12 is disassembled. At the same time, the positioning rod 19 can be disassembled when the lower positioning plate 8 is recovered, and the structure on the retaining pile is recovered.

[0048] Working principle:

[0049] Construction of support pile 1: Level the site, measure and set out to determine the pile position of each support pile 1 and the position of steel sheet pile 2. Drill and open trenches according to the pile positions of support pile 1 and steel sheet pile 2. Prepare grout according to the site strength requirements and spray grout into the drilled holes to form support pile 1. During the pouring of support pile 1, pre-embed reinforcing steel pipe 3 to its center position. At the same time, install steel sheet pile 2 into the trench to form a preliminary retaining structure.

[0050] Install the capping beam 4: Pass the bottom of the two sets of U-shaped plates 6, which are fixed by the bidirectional threaded rod 7, through the fixing groove 5 and extend to the bottom of the capping beam 4. Fix the upper positioning plate 12 to the bottom of the two U-shaped plates 6 with bolts. Then, install the capping beam 4 above the two steel sheet piles 2. After the capping beam 4 passes through multiple sets of reinforcing steel pipes 3, rotate the control handle 21 to drive the bidirectional threaded rod 7 to rotate, so that the two upper positioning plates 12 are close to the outer wall of the steel sheet pile 2 and press and limit the upper part of the steel sheet pile 2.

[0051] Install side steel plate 9: Next, pass the bottom of side steel plate 9 through the limiting groove on the top beam 4 and the upper positioning plate 12 in sequence, and fix the lower positioning plate 8 to the two side steel plates 9 on the same side with bolts, so that the lower positioning plate 8 is also tightly attached to the side wall of the steel sheet pile 2, and fix the side steel plate 9 on the upper positioning plate 12 with the fixing threaded rod 10.

[0052] Excavation of the foundation pit: The foundation pit is excavated according to actual needs. As the foundation pit is excavated deeper, the sheet pile 2 will be deformed due to the fluidity of the soft soil and the fluidity of the groundwater, and will bulge to one side of the foundation pit. At this time, in order to avoid such phenomena, the rotation of the fixed threaded rod 10 is controlled, and the side steel plate 9 is moved downward. Then, the side steel plate 9 is fixed and limited again by multiple sets of fixed threaded rods 10. The two ends of the connector are connected to the connecting hole 11 respectively. The multiple sets of connectors arranged horizontally and the side steel plate 9 arranged vertically form a mesh-like limit on the side wall of the foundation pit to prevent the side wall of the sheet pile 2 from deforming.

[0053] By positioning the positioning rod 19 on the lower positioning plate 8 against the upper surface of the foundation pit and then controlling the handle 20 to rotate, the positioning rod 19 is inserted into the upper surface of the foundation pit, further reinforcing the position of the lower positioning plate 8 and improving the deformation resistance of the sheet pile 2.

[0054] Following the above method, complete the enclosure treatment of the other side walls of the foundation pit.

[0055] The preferred embodiments of the present invention disclosed above are merely illustrative of the invention. These preferred embodiments do not exhaustively describe all details, nor do they limit the invention to any specific implementation. Clearly, many modifications and variations can be made based on the content of this specification. This specification selects and specifically describes these embodiments to better explain the principles and practical applications of the invention, thereby enabling those skilled in the art to better understand and utilize the invention. The invention is limited only by the claims and their full scope and equivalents.

Claims

1. A recyclable foundation pit retaining pile structure based on prestressed soft soil layer, comprising multiple sets of retaining piles (1) and sheet piles (2) symmetrically arranged on both sides of the multiple sets of retaining piles (1), characterized in that, The support pile (1) is equipped with a reinforcing steel pipe (3). A capping beam (4) is provided above the two sets of sheet piles (2) and multiple sets of reinforcing steel pipes (3). Four fixing slots (5) are provided above the capping beam (4). A U-shaped plate (6) is connected in the two horizontally arranged fixing slots (5). The bottom of the U-shaped plate (6) extends to the capping beam (4) and is fixedly connected to an upper positioning plate (12). Four limiting grooves are also provided above the top beam (4). Side steel plates (9) are slidably arranged inside the limiting grooves. The bottom of the side steel plates (9) passes through the top beam (4) and the upper positioning plate (12). The bottoms of the two side steel plates (9) arranged horizontally are connected to the lower positioning plate (8). The upper positioning plate (12) and the lower positioning plate (8) are both fitted to the outer wall of the sheet pile (2). The two U-shaped plates (6) are connected by a bidirectional threaded rod (7), and both sides of the bidirectional threaded rod (7) are rotatably connected to the top beam (4) through a mounting plate. The end of the bidirectional threaded rod (7) is provided with a handle (21). The lower positioning plate (8) is symmetrically provided with two mounting slots on the side wall near the sheet pile (2). A movable roller (13) is rotatably installed inside the mounting slot. The movable roller (13) is in transmission cooperation with the side wall of the sheet pile (2). The upper positioning plate (12) and the side steel plate (9) are fixedly connected by a fixed threaded rod (10). Multiple sets of arrayed connection holes (11) are provided on the opposite side walls of the side steel plate (9), and a connector is provided between two connection holes (11) located on the same horizontal line; The connector includes a first connecting steel column (14), a second connecting steel column (22), and a third connecting steel column (15). The first connecting steel column (14) is slidably fitted with one end of the second connecting steel column (22), and the other end of the second connecting steel column (22) is fixedly connected to the third connecting steel column (15). The first connecting steel column (14) and the second connecting steel column (22) are both threadedly connected to their corresponding connecting holes (11).

2. The recyclable foundation pit retaining pile structure based on soft soil prestressing according to claim 1, characterized in that: Multiple pairs of protruding plates (17) are fixedly installed on the side wall of the lower positioning plate (8) away from the sheet pile (2), and a limit shaft (18) is fixedly installed between a pair of protruding plates (17).

3. The recyclable foundation pit retaining pile structure based on soft soil prestressing according to claim 2, characterized in that: A support plate (16) is fixedly installed on the outside of the limiting shaft (18), and a positioning rod (19) is vertically threaded on the upper part of the support plate (16). A handle (20) is fixedly installed on the upper part of the positioning rod (19).

4. The recyclable foundation pit retaining pile structure based on soft soil prestressing according to claim 3, characterized in that: The reinforcement steps for the steel sheet piles (2) in the foundation pit retaining pile structure are as follows: Top pressing reinforcement: Control the rotation of the bidirectional threaded rod (7) so that the two U-shaped plates (6) drive the upper positioning plate (12) to press against the side wall of the steel sheet pile (2) and limit the upper part of the steel sheet pile (2); Central mesh reinforcement: Control the rotation of the fixed threaded rod (10), move the side steel plate (9) downward to the designated position, and then fix the side steel plate (9) by the fixed threaded rod (10). Connect the end of the connecting steel column 2 (22) and the end of the connecting steel column 1 (14) to the corresponding connecting hole (11) respectively. A mesh-like limit is formed on the side wall of the pit by multiple sets of horizontally arranged connectors and the longitudinally arranged side steel plate (9). Bottom insertion reinforcement: After the side steel plate (9) is moved down to the designated position, the positioning rod (19) on the lower positioning plate (8) is aligned with the upper surface of the pit, and the handle (20) is rotated to insert the positioning rod (19) into the upper surface of the pit to reinforce and stabilize the position of the lower positioning plate (8).

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