Deep foundation pit supporting device and construction method thereof

Abstract

This application relates to the technical field of construction engineering, and in particular to a deep foundation pit support device and its construction method. The support device includes a protective plate, a support structure, and a base frame. The base frame is installed on one side of the protective plate and is fixed to the bottom of the foundation pit. The support structure includes a traction wheel, a base, and a support rod mounted on the base frame. A transition section is provided in the middle of the support rod, hinged to the upper part of the base. A pressure support section is provided on one side of the support rod, with the straight-line distance from the transition section to the pressure support section being greater than the vertical distance from the transition section to the protective plate. A traction rope is provided on the traction wheel, with its end connected to the support rod. The traction rope is used to pull the support rod to rotate and press the pressure support section against the side of the protective plate. The end of the traction rope is connected to the lower part of the support rod on the other side of the transition section. This application, by mounting the support device on a base frame connected to the bottom of the foundation pit, using the base frame to fix the position of the support device, and employing a drive rocker structure to fix the protective plate, forms a quick and stable foundation pit support structure.

Description

Technical Field

[0001] This application relates to the technical field of building engineering, and in particular to a deep foundation pit support device and its construction method. Background Technology

[0002] Excavation pit support refers to the measures taken to support, reinforce, and protect the sidewalls and surrounding environment of an excavation pit to ensure the safety of underground structure construction and the surrounding environment. Existing excavation pit support structures include a protective plate that adheres to and supports the sidewalls of the pit, and support rods installed between the protective plate and the bottom of the pit. The protective plate is pressed tightly against the pit sidewall by the inclined support rods, thus reinforcing the pit sidewall. However, this support structure requires connecting both ends of the support rods to the protective plate and the bottom of the pit, which is not only cumbersome and labor-intensive, but also makes it difficult to control the support strength of the support rods on the protective plate. For example, in the initial installation stage, before the protective plate is inclined towards the bottom of the pit, the support rods between the protective plate and the pit are prone to loosening, resulting in insufficient clamping force and support strength. Summary of the Invention

[0003] To reduce the construction difficulty of foundation pit support and improve the stability of foundation pit support for the sidewalls of the foundation pit, this application provides a deep foundation pit support device and its construction method, which adopts the following technical solution: A deep foundation pit support device includes a protective plate, a support device, and a base frame. The base frame is installed on one side of the protective plate and is fixed to the bottom of the foundation pit. The support device includes a traction sheave, a base, and a support rod mounted on the base frame. The support rod has a transition section in the middle that is hinged to the upper part of the base. The support rod on one side of the transition section has a pressure support section. The straight-line distance from the transition section to the pressure support section is greater than the vertical distance from the transition section to the protective plate. A traction rope is installed on the traction sheave. The end of the traction rope is connected to the support rod. The traction rope is used to pull the support rod to rotate and press the pressure support section against the side of the protective plate. The end of the traction rope is connected to the lower part of the support rod on the other side of the transition section.

[0004] By adopting the above technical solution, during the support of the foundation pit, workers first place the protective plate against the side wall of the pit. Then, by driving the traction wheel to rotate, the traction rope on the traction wheel simultaneously drives the support rod to rotate, so that the pressure support part at the end of the support rod is tightly pressed against the protective plate, providing support for the protective plate. Specifically, when the end of the traction rope is connected to the lower part of the support rod on the other side of the adapter, the traction rope pulls the pressure support part of the support rod upward to rotate and press against the protective plate. Compared with existing technologies, this not only ensures the supporting effect of the support rod on the protective plate in the initial stage of support installation, but also allows adjustment of the supporting force of the support rod on the protective plate by controlling the tension of the traction rope. Furthermore, this support device is easy to replace, highly feasible to construct, and can be reused, thus saving costs.

[0005] Optionally, the base frame is a closed structure composed of several steel beams spliced ​​along the perimeter of the foundation pit.

[0006] By adopting the above technical solutions, the closure structure of the base frame can be rectangular, circular, or elliptical. The closure base frame has a high rigidity structure, and its difficult-to-deform structure can effectively share the reaction force of the guard plate on the support rod during support, thereby improving the strength and stability of the device.

[0007] Optionally, the base frame is provided with several support devices at intervals, and the transition parts of adjacent support devices are coaxially connected by a connecting shaft. Several support rods are fixed on the connecting shaft, and a drive motor for driving the traction wheel to rotate is also provided on the base frame or the bottom of the pit.

[0008] By adopting the above technical solution, the support device is driven by a drive motor, which can simultaneously drive multiple support rods on the connecting shaft to support the guard plate. This not only improves installation efficiency and support effect, but also reduces the number of device components and lowers costs.

[0009] Optionally, the base frame includes a ground rail composed of H-shaped steel beams and several platforms that slide on the ground rail. An anti-derailment structure is provided between the bottom of the platform and the ground rail, and a support device is provided on the platform.

[0010] By adopting the above technical solution, the movable platform is used to adjust the number of support devices for the local protective plate, strengthen the support strength of the local protective plate, and make the device more practical.

[0011] Optionally, the lower half of the H-shaped steel beam is embedded in the bottom of the foundation pit.

[0012] By adopting the above technical solutions, in addition to bolting the base frame to the ground or adding counterweights to the base frame, an H-beam base frame can also be used. By driving the lower half of the H-beam into the bottom of the pit, the base frame is less likely to tip over when subjected to the reaction force of the guard plate on the support device, providing sufficient fixation support for the support device. Furthermore, with the rigid closing structure formed by splicing H-beams, the base frame can achieve an even higher level of fixation support.

[0013] Optionally, the bottom of the platform is provided with a protruding part, which is inserted into the ground rail. The protruding part in the ground rail is provided with an opening, and a screw sleeve is provided in the opening. A screw is provided in the screw sleeve, and both ends of the screw pass through the ground rail and are fixed.

[0014] By adopting the above technical solution, the protruding part is locked to the ground rail, which not only prevents the platform from derailing, but also, by rotating the screw, the screw sleeve moves on the screw, driving the protruding part and the platform to move closer to or away from the guard plate, thereby controlling the distance between the platform and the support rod of the support device and the guard plate, adjusting the support area and position of the support rod pressure part on the guard plate, and improving the support effect of the support device on the guard plate.

[0015] Optionally, the pressure support is hinged to the support rod, and a shock-absorbing spring is connected between the pressure support and the support rod.

[0016] By adopting the above technical solution, the connection between the traditional support rod and the guard plate is generally rigid and has poor seismic performance. During the construction of the foundation pit, it is easy to break due to vibration. However, this application sets a shock-absorbing spring at the support part of the support rod, which effectively improves the seismic performance of the support device and extends the service life of the device.

[0017] Optionally, the base is a column structure, with reinforcing steel cables on both sides of the upper part of the base. One end of the reinforcing steel cable is connected to the upper part of the base, and the other end of the reinforcing steel cable is connected to the base frame.

[0018] By adopting the above technical solutions, the column structure can reduce the volume of the base, reduce the space occupation rate of the equipment and transportation costs, and the reinforcing steel cable can compensate for the bending resistance of the column structure, making the base structure simple and with high strength.

[0019] Optionally, the base includes an inner column and an outer column that are nested together, and a lifting cylinder is provided on the outer side of the outer column.

[0020] By adopting the above technical solution, the lifting cylinder is used to control the height of the upper support rod of the base. With the help of the traction rope whose length can be flexibly controlled, the support rod can achieve height adjustment of the support part of the guard plate, so that the support device can provide better support for the guard plate.

[0021] A construction method for a deep foundation pit support device as described above includes the following steps: installing a protective plate on the inner perimeter wall of the foundation pit; drawing a construction line parallel to the protective plate on the bottom surface of the foundation pit at a certain distance on one side of the protective plate; fixing the base frame along the construction line to the bottom surface of the foundation pit; then installing a support device including a traction wheel, a base, and a support rod on the base frame; rotating the support rod to make it abut against the protective plate; connecting the traction rope on the traction wheel to the support rod to drive the traction wheel to rotate; the traction rope pulls the support rod to move the pressure support part provided on the support rod towards the protective plate; when the pressure support part is tightly pressed against the side of the protective plate, fixing the traction wheel so that it cannot rotate, thus forming a stable foundation pit support structure.

[0022] By adopting the above technical solution, the support rod abuts against the side of the guard plate, thereby fixing the guard plate to the side wall of the pit. By rotating the traction wheel, the traction wheel drives the support rod connected by the traction rope to rotate. Because the base frame is fixed to the bottom of the pit, the base frame can fix the position of the support rod and the base. Under the pull of the traction rope, the support rod can provide sufficient support for the guard plate. This support structure also has the advantage of being applicable to the installation of guard plates under side walls with different inclination angles.

[0023] In summary, this application includes at least one of the following beneficial technical effects: This application establishes a quick and stable foundation pit support structure by placing the support device on a base frame connected to the bottom of the foundation pit, fixing the position of the support device using the base frame, and fixing the protective plate by driving the support rod of the support device to rotate.

[0024] Specifically, during the foundation pit support process, workers install protective plates on the inner perimeter of the pit, fix the base frame along the construction line to the bottom of the pit, and then install a support device including a traction sheave, base, and support rods on the base frame. Rotating the support rods causes them to press against the protective plates. The traction rope on the traction sheave is connected to the support rods, and by driving the traction sheave to rotate, the traction rope simultaneously drives the support rods to rotate, causing the pressure-bearing parts at the ends of the support rods to press firmly against the protective plates, providing support. When the end of the traction rope is connected to the lower part of the support rod on the other side of the adapter, the traction rope pulls the support rod, causing the pressure-bearing parts on the support rods to move closer to the protective plates. Once the pressure-bearing parts are firmly pressed against the side of the protective plates, the traction sheave is fixed, preventing it from rotating, thus forming a stable foundation pit support structure. Compared to existing technologies, this method not only ensures the support effect of the support rods on the protective plates during the initial installation phase but also allows for adjustment of the support force of the support rods on the protective plates by controlling the tension of the traction ropes. Attached Figure Description

[0025] Figure 1 This is a schematic diagram of the structure of this application.

[0026] Figure 2 yes Figure 1 Enlarged view of section A.

[0027] Figure 3 yes Figure 1 Enlarged view of section B in the middle.

[0028] Figure 4 This is a side view of the structure of this application.

[0029] Figure 5 This is a schematic diagram of the support device structure of this application.

[0030] Explanation of reference numerals in the attached drawings: 1. Guard plate; 11. Boss; 2. Support device; 21. Traction sheave; 211. Traction rope; 22. Base; 221. Reinforcing steel cable; 222. Inner column; 223. Outer column; 224. Lifting cylinder; 23. Support rod; 231. Adapter; 232. Pressure support; 233. Shock-absorbing spring; 3. Base frame; 31. H-beam; 32. Platform; 321. Protruding part; 322. Screw sleeve; 323. Screw; 4. Pit; 5. Connecting shaft; 6. Drive motor. Detailed Implementation

[0031] The following is in conjunction with the appendix Figures 1-5 This application will be described in further detail.

[0032] Reference Figure 1 This application discloses a deep foundation pit support device, including a protective plate 1, a support device 2, and a base frame 3. A boss 11 is provided on the lower outer side of the protective plate 1, embedded in the inner wall of the foundation pit. The base frame 3 is provided on the inner side of the protective plate 1. The base frame 3 includes a ground rail composed of H-shaped steel beams 31 and several platforms 32 slidably mounted on the ground rail. The ground rail is a closed structure composed of several H-shaped steel beams 31 spliced ​​along the perimeter of the foundation pit 4, with several platforms 32 spaced apart on the ground rail. The flanges and webs of adjacent H-shaped steel beams 31 are fixed together by steel plates and bolts. The structure formed by the H-shaped steel beams 31 can be rectangular, circular, elliptical, etc., and can be adapted to the shape of the foundation pit 4. The closed H-shaped steel beam 31 frame has high rigidity and strength; its deformation-resistant structure can effectively share the reaction force of the protective plate 1 on the support rod 23 during support, thereby improving the strength and stability of the device. Furthermore, the structure in which the lower half of the H-beam 31 is embedded in the bottom of the foundation pit 4 allows the base frame 3 as a whole to achieve a higher level of fixed support.

[0033] Reference Figures 2-5 An anti-derailment structure is provided between the bottom of the platform 32 and the ground rail, and the support device 2 is located on the platform 32. The bottom of the platform 32 has a protruding spur 321, which is inserted into the upper half of the H-shaped steel beam 31 inside the ground rail. The protruding spur 321 inside the ground rail has an opening, and a screw sleeve 322 is installed in the opening. A screw 323 is installed inside the screw sleeve 322. Both ends of the screw 323 pass through and are fixed in the through holes provided in the upper half of the H-shaped steel beam 31. The through holes of the H-shaped steel beam 31 are arranged in multiple rows along the length of the H-shaped steel beam 31. By inserting and locking the screws 323 into the through holes at different positions, the position of the platform 32 and the upper support device 2 can be adjusted. By moving the position of the platform 32, the number of support devices 2 of the local guard plate 1 can be adjusted, strengthening the support strength of the local guard plate 1 and making the device more practical.

[0034] The support device 2 includes a traction sheave 21, a base 22, and a support rod 23 mounted on a platform 32. The base 22 is a column structure, comprising an inner column 222 and an outer column 223 that are nested together. A lifting cylinder 224 is provided on the outer side of the outer column 223. Reinforcing steel cables 221 are provided on both sides of the upper inner column 222 of the base 22. One end of the reinforcing steel cable 221 is connected to the upper inner column 222 of the base 22, and the other end of the reinforcing steel cable 221 is connected to the base frame 3. The support rod 23 has a transition part 231 in the middle that is hinged to the upper part of the base 22. The support rod 23 on one side of the transition part 231 has a pressure support part 232. The pressure support part 232 is an independent block structure. One end of the pressure support part 232 is hinged to the support rod 23, and a shock-absorbing spring 233 is connected between the other end of the pressure support part 232 and the support rod 23. The straight-line distance from the adapter 231 to the support 232 is greater than the vertical distance from the adapter 231 to the guard plate 1, so that the support 232 can contact the guard plate 1 when rotating.

[0035] The traction sheave 21 is equipped with a traction rope 211, the end of which is connected to the support rod 23. The traction rope 211 is used to pull the support rod 23 to rotate and cause the pressure support 232 to press against the side of the guard plate 1. The end of the traction rope 211 is connected to the lower part of the support rod 23 on the other side of the adapter 231. At this time, the support rod 23 and the base 22 form a lever structure. By adjusting the length of the support rod 23, the lever arm length on one side of the support rod 23 can be increased, thereby improving the support effect of the support rod 23 on the guard plate 1 under the same traction rope 211 tension. Alternatively, if the lever structure is not used, the end of the traction rope 211 can be connected to the support rod 23 on the lower side of the pressure support 232, and the support rod 23 can be pulled down directly to press against the guard plate 1. In this case, the traction sheave 21 requires a greater driving force.

[0036] The transition parts 231 of adjacent support devices 2 are coaxially connected by a connecting shaft 5. Several support rods 23 are fixed on the connecting shaft 5. A drive motor 6 for driving the traction sheave 21 to rotate is also provided on the bottom surface of the pit 4. The traction sheave 21 adopts a device with a manual pin locking mechanism or an electronically controlled brake shoe braking device, which can lock the traction sheave 21 after the support rods 23 press against the guard plate 1, so that it cannot rotate.

[0037] A construction method for a deep foundation pit support device includes the following steps: Step 1: Install a protective plate 1 on the inner wall of the foundation pit 4. Embed the lower outer protrusion 11 of the protective plate 1 into the inner wall of the foundation pit. Draw a construction line parallel to the protective plate 1 on the bottom surface of the foundation pit 4 at a certain distance on one side of the protective plate 1. Drive the lower half of the H-beam 31 into the bottom surface of the foundation pit 4 along the construction line using a pile driver. Then, connect and fix the H-beam 31 arranged around the inner wall of the foundation pit 4 with angle steel and bolts to form an enclosed structure.

[0038] Step two: Several sets of platforms 32 equipped with support devices 2 are placed on the upper half of the H-shaped steel beam 31. The protruding parts 321 of the platforms 32 are inserted between the two flange plates of the upper half of the H-shaped steel beam 31. Bolts are used to fix the platforms 32 to the H-shaped steel beam 31 through the protruding parts 321 and the H-shaped steel beam 31. Furthermore, by rotating the bolts, the protruding parts 321 and the platforms 32 are moved through the screw sleeve 322 structure of the protruding parts 321, so as to make fine adjustments to the position of the platforms 32.

[0039] Step 4: Loosen the reinforcing steel cable 221 on the inner column 222 of the base 22, start the lifting cylinder 224 on the side of the column of the base 22, adjust the height of the base 22, that is, the height of the support rod 23 of the support device 2, and then re-tighten the reinforcing steel cable 221.

[0040] Step 5: Connecting shaft 5 and the adapter 231 of each adjacent support device 2 are connected in series and coaxially. Several support rods 23 are fixed on the connecting shaft 5.

[0041] Step 6: Rotate the support rods 23 of each support device 2 so that the support rods 23 abut against the guard plate 1. Connect the traction rope 211 on the traction wheel 21 to the support rods 23. Start the drive motor 6 connected to the traction wheel 21 to drive the traction wheel 21 to rotate. The traction rope 211 pulls the support rods 23 so that the pressure support part 232 provided on the support rods 23 moves closer to the guard plate 1. When the pressure support part 232 is pressed tightly against the side of the guard plate 1, the traction wheel 21 is fixed so that the traction wheel 21 cannot rotate, forming a stable foundation pit 4 support structure.

[0042] This application uses the support rod 23's pressure support 232 to abut against the side of the guard plate 1, thereby fixing the guard plate 1 to the side wall of the pit 4. By rotating the traction wheel 21, the traction wheel 21 drives the support rod 23 connected to the traction rope 211 to rotate. Because the base frame 3 is fixed to the bottom of the pit 4, the base frame 3 can fix the position of the support rod 23 and the base 22. Under the pull of the traction rope 211, the support rod 23 can provide sufficient support for the guard plate 1. Compared with the prior art, this application not only ensures the support effect of the support rod 23 on the guard plate 1 in the initial stage of support installation, but also allows the support force of the support rod 23 on the guard plate 1 to be adjusted by controlling the tension of the traction rope 211.

[0043] The above are all preferred embodiments of this application, and are not intended to limit the scope of protection of this application. Therefore, all equivalent changes made in accordance with the structure, shape and principle of this application should be covered within the scope of protection of this application.

Claims

1. A deep foundation pit support device, characterized in that: The device includes a guard plate (1), a support device (2) and a base frame (3). The base frame (3) is set on one side of the guard plate (1) and is fixed to the bottom of the pit (4). The base frame (3) includes a ground rail composed of H-shaped steel beams (31) and several platforms (32) that are slidably set on the ground rail. The bottom of the platform (32) is provided with an anti-derailment structure between it and the ground rail. The support device (2) includes a traction wheel (21), a base (22) and a support rod (23) set on the platform (32). The support rod (23) has a transition part (231) that is hinged to the upper part of the base (22) in the middle. The support rod (23) on one side of the adapter (231) is provided with a pressure support (232). The straight distance from the adapter (231) to the pressure support (232) is greater than the vertical distance from the adapter (231) to the guard plate (1). The traction wheel (21) is provided with a traction rope (211). The end of the traction rope (211) is connected to the support rod (23). The traction rope (211) is used to pull the support rod (23) to rotate and make the pressure support (232) press against the side of the guard plate (1). The end of the traction rope (211) is connected to the lower part of the support rod (23) on the other side of the adapter (231). The base frame (3) is provided with several support devices (2) at intervals. The connecting parts (231) of adjacent support devices (2) are coaxially connected by a connecting shaft (5). Several support rods (23) are fixed on the connecting shaft (5). The bottom surface of the base frame (3) or the pit (4) is also provided with a drive motor (6) for driving the traction wheel (21) to rotate. The drive motor (6) drives the support device (2) to work and can drive multiple support rods (23) on the connecting shaft to support the guard plate (1). The base (22) includes an inner column (222) and an outer column (223) that are nested together. A lifting cylinder (224) is provided on the outside of the outer column (223). The lifting cylinder (224) is used to control the height of the upper support rod of the base. The base (22) is a column structure. The inner column (222) at the top of the base (22) is provided with reinforcing steel cables (221). One end of the reinforcing steel cable (221) is connected to the inner column (222) at the top of the base (22), and the other end of the reinforcing steel cable (221) is connected to the base frame (3).

2. The deep foundation pit support device according to claim 1, characterized in that: The base frame (3) is a closed structure composed of several steel beams spliced ​​along the perimeter of the pit (4).

3. The deep foundation pit support device according to claim 1, characterized in that: The lower half of the H-shaped steel beam (31) is embedded in the bottom of the foundation pit (4).

4. The deep foundation pit support device according to claim 1, characterized in that: The bottom of the platform (32) is provided with a protruding part (321), which is inserted into the ground rail. The protruding part (321) in the ground rail is provided with an opening, and a screw sleeve (322) is provided in the opening. A screw (323) is provided in the screw sleeve (322), and both ends of the screw (323) pass through the ground rail and are fixed.

5. The deep foundation pit support device according to claim 1, characterized in that: The pressure support (232) is hinged to the support rod (23), and a shock-absorbing spring (233) is connected between the pressure support (232) and the support rod (23).

6. A construction method for a deep foundation pit support device as described in claim 1, characterized in that, Includes the following steps: A protective plate (1) is installed on the inner perimeter wall of the foundation pit (4). A construction line parallel to the protective plate (1) is drawn on the bottom surface of the foundation pit (4) at a certain distance on one side of the protective plate (1). The base frame (3) is fixed to the bottom surface of the foundation pit (4) along the construction line. Then, the support device (2) including the traction wheel (21), the base (22) and the support rod (23) is installed on the base frame (3). The support rod (23) is rotated so that the support rod (23) abuts against the protective plate (1). The traction wheel (21) is then moved to the bottom surface of the foundation pit (4). The traction rope (211) on the pulley (21) is connected to the support rod (23), driving the traction wheel (21) to rotate. The traction rope (211) pulls the support rod (23) so that the pressure support part (232) provided on the support rod (23) moves closer to the guard plate (1). When the pressure support part (232) presses tightly against the side of the guard plate (1), the traction wheel (21) is fixed so that the traction wheel (21) cannot rotate, forming a stable foundation pit (4) support structure.

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