An adjustable foundation pit support structure

Abstract

This invention belongs to the field of foundation pit support technology, specifically relating to an adjustable foundation pit engineering support structure. It includes support units, each comprising a support base plate and a support frame plate. The support base plate rests against the foundation pit wall, and the support frame plate is connected to the support base plate via an adjustable support. A cross bracing device supports the support frame plates of two support units in opposite directions, and the two support units are mutually supported by the cross bracing device, with the adjustable support buffering the deformation pressure of the foundation pit wall. Support units in the same direction are spliced ​​together. This invention provides an adjustable foundation pit engineering support structure, employing an adjustable support structure that forms a recoverable elastic support system between the support base plate and the support frame plate. After pressure is unloaded, it can return to its original shape, improving the durability and reusability of the support structure.

Description

Technical Field

[0001] This invention belongs to the field of foundation pit support technology, specifically relating to an adjustable foundation pit engineering support structure. Background Technology

[0002] Foundation pit engineering is a crucial stage in building construction, and the safety and adaptability of its support structure directly affect the overall stability and progress of the project. Currently, commonly used foundation pit support structures mostly employ rigid support methods, such as steel supports and concrete supports. While these structures possess a certain bearing capacity when subjected to lateral earth pressure on the foundation pit, their deformation adaptability is poor. When the foundation pit wall experiences significant pressure due to soil deformation, groundwater changes, or surrounding loads, rigid supports are prone to plastic deformation or localized failure, and are difficult to restore to their original state after pressure relief, affecting the continuity and reliability of the support effect. Furthermore, existing support structures rely heavily on external drainage facilities to address foundation pit seepage issues, lacking a hydrological management mechanism organically integrated with the support structure itself. This easily leads to soil erosion and softening of the soil behind the support, further exacerbating pit wall deformation and increasing the burden on the support.

[0003] Therefore, there is a need for a foundation pit support structure that has adaptive adjustment capabilities, can effectively alleviate the deformation pressure of the pit wall, and has integrated drainage functions, so as to improve the safety, economy and construction convenience of foundation pit projects. Summary of the Invention

[0004] This invention aims to improve the shortcomings of current rigid support structures for foundation pits in terms of deformation adaptability, recovery capacity, and drainage mechanism.

[0005] This invention provides the following technical solution: an adjustable foundation pit support structure, comprising support units, each support unit including a support base plate and a support frame plate; the support base plate is attached to the foundation pit wall, and the support frame plate is connected to the support base plate by an adjustable support; a cross bracing device supports the support frame plates of two support units in opposite directions, and the two support units are supported by the cross bracing device to provide mutual reaction force support; the support units buffer the deformation pressure of the foundation pit wall through the adjustable support; support units in the same direction are spliced ​​together.

[0006] Furthermore, the adjustable support includes radially stacked arc-shaped spring plates, which are tightened together by U-shaped tie rods, fixing plates, and nuts. From the outermost layer to the innermost layer, the length of the arc-shaped spring plates decreases layer by layer. An outer liner is placed between the outermost arc-shaped spring plate and the crossbar of the U-shaped tie rod, and an inner liner is placed between the innermost arc-shaped spring plate and the fixing plate.

[0007] The crossbar of the U-shaped tie rod is fixedly connected to the support base plate, and the two arc ends of the outermost arc spring plate are connected to the support frame plate through a sliding pair.

[0008] Furthermore, the support plate is fixed with slide rails, and the slide rails on both sides of the arc-shaped spring plate are a group, with the slide grooves of the slide rails in the same group facing the arc-shaped spring plate; the two arc ends of the outermost arc-shaped spring plate are provided with insertion holes, and support shafts are inserted into the insertion holes. The convex sliders at both ends of the support shafts slide and engage with the slide grooves of the slide rails on both sides respectively.

[0009] Furthermore, the support unit also includes a seepage drainage mechanism; the seepage drainage mechanism includes a seepage conduit, a seepage collection chamber, and a water collection assembly;

[0010] The seepage collection chamber is installed on the side of the support base plate facing the support frame plate. The seepage collection chamber extends continuously in the horizontal direction and is arranged at intervals in the vertical direction on the support base plate. The seepage conduit is inserted into the support base plate within the range of the seepage collection chamber. The drain outlet of the seepage conduit is connected to the seepage collection chamber. The inlet of the seepage conduit is located on the side of the support base plate facing the pit wall.

[0011] The seepage collection chambers are connected by downpipes, and the lowest seepage collection chamber is connected to the water collection component.

[0012] Furthermore, the water collection assembly includes a drainage pipe and a water storage container. The water storage container is installed on the outer side of the support plate. One end of the drainage pipe is connected to the lowest seepage collection chamber, and the other end is connected to the water storage container. A section of corrugated pipe is connected in the drainage pipe.

[0013] Furthermore, the end of the seepage pipe facing the pit wall is a closed cone, and the inlets are evenly distributed around the seepage pipe. A seepage chamber is connected to the seepage pipe outside the inlet. The seepage outlet of the seepage chamber is connected to the inlet of the seepage pipe. The seepage inlet of the seepage chamber runs through the seepage chamber from front to back and is connected to the seepage outlet. An inclined soil cover is connected to the seepage chamber to block the seepage inlet. The drainage outlet of the seepage pipe has a conical constriction structure, and a trumpet-shaped water-stop ring is set at the junction of the seepage pipe and the seepage collection chamber.

[0014] Furthermore, a T-shaped pipe is installed between the drain pipe and the water storage container. The first port of the T-shaped pipe is connected to the drain pipe, a piston is nested inside the second port, and a branch pipe between the first and second ports is connected to the water storage container.

[0015] A swing arm is hinged to the outer side of the support plate. A rope is connected to the part of the swing arm above the hinge point, and a sector gear is connected to the part of the swing arm below the hinge point. A guide sleeve is provided on the outer side of the support plate. A push-pull rod is slidably inserted in the guide sleeve. The rack on the push-pull rod meshes with the sector gear. The push-pull rod and the piston are connected by a handle that slides through the support plate.

[0016] The vertical rod of the U-shaped tie rod passes through the support plate and connects to the push-pull plate. A limit tube is installed on the outer side of the support plate. The end of the pull rope away from the swing arm passes through the limit tube and connects to the push-pull plate. A spring connects the push-pull rod and the support plate.

[0017] Furthermore, the support units are spliced ​​together horizontally by support base plates and vertically by support frame plates;

[0018] The support base plate has slots, and insert plates are inserted between the slots of two horizontally adjacent support base plates.

[0019] The four corners of the support frame plate are equipped with horizontal ear plates, and the horizontal ear plates of two longitudinally adjacent support frame plates are connected by pins.

[0020] Furthermore, the pull rope is connected to the hanging ring on the push-pull plate via a hook.

[0021] Furthermore, grouting anchors are connected to the support base plate, and the support base plate can be connected to the pit wall through the grouting anchors.

[0022] Compared with the prior art, the advantages of the present invention are:

[0023] This invention provides an adjustable foundation pit support structure, which is composed of multiple layers of arc-shaped spring plates. It has good elastic deformation capacity and can effectively absorb and buffer the lateral pressure on the foundation pit wall caused by soil deformation, groundwater changes or external loads. The adjustable support structure forms a recoverable elastic support system between the support base plate and the support frame plate. It can return to its original shape after the pressure is unloaded, which improves the durability and reusability of the support structure.

[0024] The support unit adopts a horizontal plate splicing and vertical pin connection method, which facilitates quick on-site assembly and disassembly and adapts to different pit sizes; the support base plate is equipped with grouting anchor rods to enhance the connection stability with the pit wall and improve the reliability of the overall support system.

[0025] The system is equipped with a seepage drainage mechanism, which includes a seepage conduit, a seepage collection chamber, and a water collection component. This mechanism enables active drainage and centralized flow diversion, effectively removing water accumulated behind the foundation pit and preventing soil softening and erosion. The drainage system is integrated with the support structure, reducing reliance on external drainage facilities and improving construction efficiency and economy. Attached Figure Description

[0026] Figure 1 This is a schematic diagram of an adjustable foundation pit support structure.

[0027] Figure 2 This is a schematic diagram of the support unit assembly.

[0028] Figure 3This is a schematic diagram of a support unit;

[0029] Figure 4 This is a schematic diagram of a seepage conduit;

[0030] Figure 5 This is a schematic diagram of a seepage and drainage mechanism;

[0031] Figure 6 This is a schematic diagram of a seepage conduit;

[0032] Figure 7 This is a schematic diagram of the seepage chamber;

[0033] Figure 8 This is a schematic diagram showing the interaction between the swing arm and the push-pull rod.

[0034] Figure 9 for Figure 8 Enlarged view of point A in the middle;

[0035] Figure 10 This is a schematic diagram of a T-junction pipe;

[0036] Figure 11 This is a schematic diagram showing the installation and positioning of the adjustable support.

[0037] Figure 12 Schematic diagram of adjustable support Figure 1 ;

[0038] Figure 13 Schematic diagram of adjustable support Figure 2 .

[0039] In the diagram: 1-Support base plate; 1.1-Slot; 1.2-Insertion plate; 1.3-Grouting anchor bolt;

[0040] 2-Support plate; 2.1-Horizontal lug plate; 2.2-Pin;

[0041] 3-Adjustable support; 3.1-Arc-shaped spring plate; 3.2-U-shaped tie rod; 3.3-Fixing plate; 3.4-Nut; 3.5-Outer liner plate; 3.6-Inner liner plate; 3.7-Slide rail; 3.8-Support shaft; 3.9-Convex slider;

[0042] 4-Cross bracing device;

[0043] 5-Water seepage and drainage mechanism; 5.1-Water seepage conduit; 5.1.1-French-shaped waterstop ring; 5.1.2-Water inlet; 5.1.3-Drain outlet; 5.2-Water seepage collection chamber; 5.3-Downpipe; 5.4-Drainage conduit; 5.4.1-Corrugated pipe; 5.5-Water storage container; 5.6-Water seepage chamber; 5.6.1-Soil barrier; 5.6.2-Water seepage outlet; 5.6.3-Water seepage inlet; 5.7-Tee pipe; 5.7.1-Branch pipe; 5.8-Piston;

[0044] 6-Swing arm; 7-Pull rope; 7.1-Hook; 8-Sector gear; 9-Guide sleeve; 10-Push-pull rod; 10.1-Rack; 11-Handle; 12-Push-pull plate; 12.1-Hanging ring; 13-Limit tube; 14-Spring. Detailed Implementation

[0045] To more clearly illustrate the technical solutions in the embodiments of the present 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 present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0046] like Figure 1 , Figure 2 As shown: An adjustable foundation pit support structure includes support units, each including a support base plate 1 and a support frame plate 2. The support base plate 1 is attached to the foundation pit wall, and the support frame plate 2 is connected to the support base plate 1 by an adjustable support 3. A cross bracing device 4 supports the support frame plates 2 of two support units in opposite directions. The two support units are supported by the cross bracing device 4, which provides mutual reaction force support, forming a stable internal support frame. The support units buffer the deformation pressure of the foundation pit wall through the adjustable support 3. The cross bracing device 4 is made of bolted steel pipes, and a hydraulic support is installed at the end of the cross bracing device 4 to adjust the supporting force.

[0047] The support base plate 1 is connected to the grouting anchor rod 1.3, which allows the support base plate 1 to be connected to the pit wall. This ensures close contact and interaction between the support base plate 1 and the soil, prevents the support base plate 1 from detaching from the pit wall, and improves the stability and safety of the system.

[0048] When the soil in the pit wall deforms, generating lateral earth pressure, this pressure is first transmitted to the support base plate 1 through the interaction between the soil and the grouting anchor 1.3. Subsequently, the pressure is transmitted to the support frame plate 2 through the adjustable support 3, and finally balanced by the reverse support force provided by the cross bracing device 4. In this process, the adjustable support 3, as the core buffer and adaptive element, effectively buffers and absorbs the instantaneously increased pressure peak through its unique elastic deformation, avoiding rigid failure of the structure. It also allows the support system to adapt to the deformation of the pit wall within a certain range, thereby significantly improving the safety and reliability of the support system.

[0049] like Figure 2 , Figure 3 , Figure 4As shown: Support units in the same direction are spliced ​​together to form a well-integrated support wall. Support units are spliced ​​laterally using support base plates 1 and longitudinally using support frame plates 2. Support base plates 1 have slots 1.1, and insert plates 1.2 are inserted between slots 1.1 of two adjacent support base plates 1 laterally, ensuring the continuity of the support wall in the lateral direction and effectively transferring shear force. Horizontal ear plates 2.1 are provided at the four corners of the support frame plates 2, and the horizontal ear plates 2.1 of two adjacent support frame plates 2 in the longitudinal direction are connected by pins 2.2, ensuring that the support wall also forms a unified whole in the vertical direction, sharing the load. This splicing method achieves standardization and assembly of the support structure, significantly reducing on-site welding or special processing, shortening the construction period, and facilitating the dismantling and reuse of the support structure, conforming to the concept of green construction.

[0050] like Figure 11 , Figure 12 , Figure 13 As shown: The adjustable support 3 includes radially stacked arc-shaped spring plates 3.1. The arc-shaped spring plates 3.1 are tightened together by U-shaped tie rods 3.2, fixed plates 3.3 and nuts 3.4. From the outer layer to the inner layer, the length of the arc-shaped spring plates 3.1 decreases layer by layer, forming a gradient stiffness system. An outer liner plate 3.5 is placed between the outermost arc-shaped spring plate 3.1 and the crossbar of the U-shaped tie rod 3.2, and an inner liner plate 3.6 is placed between the innermost arc-shaped spring plate 3.1 and the fixed plate 3.3. The preload is evenly distributed between the outer liner plate 3.5 and the inner liner plate 3.6 to prevent the arc-shaped spring plates 3.1 from shifting between layers.

[0051] The crossbar of the U-shaped tie rod 3.2 is fixedly connected to the support base plate 1. The two arc ends of the outermost arc-shaped spring plate 3.1 are connected to the support frame plate 2 through a sliding pair. A slide rail 3.7 is fixed on the support frame plate 2. The slide rails 3.7 on both sides of the arc-shaped spring plate 3.1 form a group, and the grooves of the slide rails 3.7 in the same group face the arc-shaped spring plate 3.1. The two arc ends of the outermost arc-shaped spring plate 3.1 are provided with insertion holes, and a support shaft 3.8 is inserted into the insertion holes. The convex sliders 3.9 at both ends of the support shaft 3.8 slide and engage with the grooves of the slide rails 3.7 on both sides.

[0052] The outermost arc-shaped spring plate 3.1 forms a sliding pair with the slide rail 3.7 on the support plate 2 through the support shaft 3.8 and the convex slider 3.9, allowing the arc-shaped spring plate 3.1 to slide along the slide rail 3.7 when under pressure; when the pit wall deforms or the soil pressure increases, the pressure is transmitted to the adjustable support 3 through the support plate 1, and the arc-shaped spring plate 3.1 undergoes elastic bending to absorb and store energy; after the pressure is unloaded, the arc-shaped spring plate 3.1 returns to its original shape under its own elastic action, driving the entire support unit to return to its original shape.

[0053] like Figure 3 , Figure 4 , Figure 5As shown: The support unit also includes a seepage drainage mechanism 5; the seepage drainage mechanism 5 includes a seepage conduit 5.1, a seepage collection chamber 5.2, and a water collection assembly;

[0054] The seepage collection chamber 5.2 is installed on the side of the support base plate 1 facing the support frame plate 2. The seepage collection chamber 5.2 extends continuously in the transverse direction and is arranged at intervals in the longitudinal direction on the support base plate 1. The seepage conduit 5.1 is inserted into the support base plate 1 within the range of the seepage collection chamber 5.2. The drain outlet 5.1.3 of the seepage conduit 5.1 is connected to the seepage collection chamber 5.2. The inlet 5.1.2 of the seepage conduit 5.1 is located on the side of the support base plate 1 facing the pit wall. After the support base plate 1 is attached to the pit wall, the seepage conduit 5.1 is inserted into the soil. The seepage water in the soil is introduced into the seepage collection chamber 5.2 through the seepage conduit 5.1.

[0055] The seepage collection chambers 5.2 are connected by downpipes 5.3 to guide the upper water collection to the lowest layer. The seepage collection chamber 5.2 at the lowest layer is connected to the water collection component.

[0056] The water collection assembly includes a drainage conduit 5.4 and a water storage container 5.5. The water storage container 5.5 is installed on the outer side of the support plate 2. One end of the drainage conduit 5.4 is connected to the lowest seepage collection chamber 5.2, and the other end is connected to the water storage container 5.5. The water storage container 5.5 and the drainage conduit 5.4 are connected by a spiral joint. The water in the water storage container 5.5 is easy to pour out when it is full. The water storage container 5.5 is a transparent plastic bottle. A section of corrugated pipe 5.4.1 is connected to the drainage conduit 5.4. The corrugated pipe 5.4.1 can compensate for pipe displacement or stress that may be caused by the deformation of the support unit.

[0057] like Figure 10 As shown: A tee pipe 5.7 is provided between the drain pipe 5.4 and the water storage container 5.5. The first port of the tee pipe 5.7 is connected to the drain pipe 5.4, the second port is nested with a piston 5.8, and the branch pipe 5.7.1 between the first port and the second port is connected to the water storage container 5.5.

[0058] like Figure 3 , Figure 5 , Figure 8 As shown: A swing arm 6 is hinged to the outer side of the support plate 2. A pull rope 7 is connected to the part of the swing arm 6 above the hinge point, and a sector gear 8 is connected to the part of the swing arm 6 below the hinge point. A guide sleeve 9 is provided on the outer side of the support plate 2. A push-pull rod 10 is slidably inserted into the guide sleeve 9. The rack 10.1 on the push-pull rod 10 meshes with the sector gear 8. The push-pull rod 10 and the piston 5.8 are connected by a handle 11 that slides through the support plate 2.

[0059] The vertical rod of the U-shaped tie rod 3.2 passes through the support plate 2 and is connected to the push-pull plate 12. A limit tube 13 is provided on the outer side of the support plate 2. The end of the pull rope 7 away from the swing arm 6 passes through the limit tube 13 and is connected to the push-pull plate 12. A spring 14 is connected between the push-pull rod 10 and the support plate 2.

[0060] When the soil pressure increases, causing the adjustable support 3 to be compressed, the distance between the support base plate 1 and the support frame plate 2 is compressed. The vertical rod of the U-shaped tie rod 3.2 extends outward relative to the support frame plate 2 (away from the direction of the pit wall), causing the push-pull plate 12 at its end to move together. The push-pull plate 12 pulls the upper end of the swing arm 6 through the pull rope 7. The swing arm 6 rotates around the hinge point in its middle, pushing the sector gear 8 at its lower end. The sector gear 8 meshes with the rack 10.1 on the push-pull rod 10, converting the rotational motion of the swing arm 6 into the linear motion of the push-pull rod 10.

[0061] The push-pull rod 10 pushes the piston 5.8 through the handle 11 to move it in the second opening of the three-way pipe 5.7. When the piston 5.8 is pushed in, a certain impact air pressure is generated. Since the water storage container 5.5 is a closed space, it will not be depressurized from the water storage container 5.5 through the branch pipe 5.7.1. The impact air pressure acts on the drain pipe 5.4, which helps to clean the silt deposited in the drain pipe 5.4.

[0062] When the pressure on the pit wall decreases, the adjustable support 3 rebounds, the U-shaped tie rod 3.2 retracts, and with the assistance of the spring 14, the push-pull rod 10 drives the piston 5.8 to reset. This process realizes the automatic unblocking of the drainage pipe 5.4 by utilizing the displacement of the U-shaped tie rod 3.2 relative to the support plate 2, preventing the drainage pipe 5.4 from becoming blocked.

[0063] like Figure 9 As shown: The pull rope 7 is connected to the hanging ring 12.1 on the push-pull plate 12 via the hook 7.1. When the hook 7.1 is removed, the swing arm 6 can be manually moved to clear the blockage.

[0064] like Figure 6 , Figure 7As shown: The end of the seepage conduit 5.1 facing the pit wall is a closed cone, facilitating penetration into the soil. Inlets 5.1.2 are evenly distributed around the seepage conduit 5.1. A seepage chamber 5.6 is connected to the seepage conduit 5.1 outside the inlets 5.1.2. The seepage outlet 5.6.2 of the seepage chamber 5.6 is interconnected with the inlets 5.1.2 of the seepage conduit 5.1. The seepage inlet 5.6.3 of the seepage chamber 5.6 penetrates the seepage chamber 5.6 from front to back and is interconnected with the seepage outlet 5.6.2. Groundwater flows through the seepage chamber 5.6. After collection, the water enters the seepage conduit 5.1 through the inlet 5.1.2. The seepage chamber 5.6 is connected to a sloped soil shield 5.6.1 that blocks the seepage inlet 5.6.3 to prevent soil particles from clogging the seepage inlet 5.6.3 and ensure smooth water flow. The drain outlet 5.1.3 of the seepage conduit 5.1.3 has a tapered constriction structure. A horn-shaped water-stop ring 5.1.1 is installed at the connection between the seepage conduit 5.1 and the seepage collection chamber 5.2 to prevent water leakage at the connection between the seepage conduit 5.1 and the seepage collection chamber 5.2.

[0065] The above description of the disclosed embodiments enables those skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. An adjustable foundation pit support structure, characterized in that: The system includes a support unit, which includes a support base plate (1) and a support frame plate (2). The support base plate (1) is attached to the pit wall, and the support frame plate (2) is connected to the support base plate (1) by an adjustable support (3). The support frame plates (2) of the two support units in opposite directions are supported by a cross bracing device (4). The two support units are supported by the cross bracing device (4) and provide mutual reaction force support. The support units buffer the deformation pressure of the pit wall through the adjustable support (3). Support units in the same direction are spliced ​​together. The adjustable support (3) includes radially stacked arc-shaped spring plates (3.1). The arc-shaped spring plates (3.1) are tightened together by a U-shaped tie rod (3.2) in conjunction with a fixing plate (3.3) and a nut (3.4). From the outer layer to the inner layer, the length of the arc-shaped spring plates (3.1) is gradually shortened. An outer liner plate (3.5) is placed between the outermost arc-shaped spring plate (3.1) and the crossbar of the U-shaped tie rod (3.2). An inner liner plate (3.6) is placed between the innermost arc-shaped spring plate (3.1) and the fixing plate (3.3). The crossbar of the U-shaped tie rod (3.2) is fixedly connected to the support base plate (1), and the two arc ends of the outermost arc spring plate (3.1) are connected to the support frame plate (2) through a sliding pair; The support unit further includes a seepage drainage mechanism (5); the seepage drainage mechanism (5) includes a seepage conduit (5.1), a seepage collection chamber (5.2), and a water collection component; The seepage collection chamber (5.2) is installed on the side of the support base plate (1) facing the support frame plate (2). The seepage collection chamber (5.2) extends horizontally and is arranged longitudinally on the support base plate (1). The seepage conduit (5.1) is inserted into the support base plate (1) within the range of the seepage collection chamber (5.2). The drain outlet (5.1.3) of the seepage conduit (5.1) is connected to the seepage collection chamber (5.2). The inlet (5.1.2) of the seepage conduit (5.1) is located on the side of the support base plate (1) facing the pit wall. The seepage collection chambers (5.2) are connected by downpipes (5.3), and the lowest seepage collection chamber (5.2) is connected to the water collection assembly; The water collection assembly includes a drainage pipe (5.4) and a water storage container (5.5). The water storage container (5.5) is installed on the outer side of the support plate (2). One end of the drainage pipe (5.4) is connected to the lowest seepage collection chamber (5.2), and the other end is connected to the water storage container (5.5). A section of corrugated pipe (5.4.1) is connected in the drainage pipe (5.4). A three-way pipe (5.7) is provided between the drain pipe (5.4) and the water storage container (5.5). The first port of the three-way pipe (5.7) is connected to the drain pipe (5.4), a piston (5.8) is nested inside the second port, and a branch pipe (5.7.1) between the first port and the second port is connected to the water storage container (5.5). A swing arm (6) is hinged to the outer side of the support plate (2). A pull rope (7) is connected to the part of the swing arm (6) above the hinge point, and a sector gear (8) is connected to the part of the swing arm (6) below the hinge point. A guide sleeve (9) is provided on the outer side of the support plate (2). A push-pull rod (10) is slidably inserted in the guide sleeve (9). The rack (10.1) on the push-pull rod (10) meshes with the sector gear (8). The push-pull rod (10) and the piston (5.8) are connected by a handle (11) that slides through the support plate (2). The vertical rod of the U-shaped tie rod (3.2) passes through the support plate (2) and is connected to the push-pull plate (12). A limit tube (13) is provided on the outer side of the support plate (2). The end of the pull rope (7) away from the swing arm (6) passes through the limit tube (13) and is connected to the push-pull plate (12). A spring (14) is connected between the push-pull rod (10) and the support plate (2).

2. The adjustable foundation pit support structure according to claim 1, characterized in that: The support plate (2) is fixed with slide rails (3.7). The slide rails (3.7) on both sides of the arc spring plate (3.1) are a group, and the grooves of the slide rails (3.7) in the same group face the arc spring plate (3.1). The two arc ends of the outermost arc spring plate (3.1) are provided with insertion holes, and a support shaft (3.8) is inserted into the insertion holes. The convex sliders (3.9) at both ends of the support shaft (3.8) slide and fit with the grooves of the slide rails (3.7) on both sides respectively.

3. The adjustable foundation pit support structure according to claim 1, characterized in that: The end of the seepage conduit (5.1) facing the pit wall is a closed cone. Inlets (5.1.2) are evenly distributed around the seepage conduit (5.1). A seepage chamber (5.6) is connected to the seepage conduit (5.1) outside the inlets (5.1.2). The seepage outlet (5.6.2) of the seepage chamber (5.6) is interconnected with the inlet (5.1.2) of the seepage conduit (5.1). The seepage inlet of the seepage chamber (5.6) is... (5.6.3) The seepage chamber (5.6) runs through the front and back and is interconnected with the seepage outlet (5.6.2). The seepage chamber (5.6) is connected to a soil cover (5.6.1) that is inclined and shields the outside of the seepage inlet (5.6.3). The drainage outlet (5.1.3) of the seepage conduit (5.1) has a conical constriction structure. A trumpet-shaped water stop ring (5.1.1) is provided at the junction of the seepage conduit (5.1) and the seepage collection chamber (5.2).

4. The adjustable foundation pit support structure according to claim 1, characterized in that: The support units are spliced ​​together horizontally by support base plates (1) and vertically by support frame plates (2); A slot (1.1) is opened on the support base plate (1), and a plug plate (1.2) is inserted between the slots (1.1) of two horizontally adjacent support base plates (1). The four corners of the support frame plate (2) are provided with horizontal ear plates (2.1), and the horizontal ear plates (2.1) of two longitudinally adjacent support frame plates (2) are connected by pins (2.2).

5. The adjustable foundation pit support structure according to claim 1, characterized in that: The pull rope (7) is fastened to the hanging ring (12.1) on the push-pull plate (12) by a hook (7.1).

6. The adjustable foundation pit support structure according to claim 1, characterized in that: The support base plate (1) is connected to a grouting anchor rod (1.3), and the support base plate (1) can be connected to the pit wall through the grouting anchor rod (1.3).

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