Subway super-wide deep foundation pit lattice column underpinning device and use method thereof

Abstract

The present application relates to the technical field of underpinning device, in particular to a subway super-wide deep foundation pit lattice column underpinning device and its using method.The present application discloses a subway super-wide deep foundation pit lattice column underpinning device, which comprises a foundation pit lattice column body and four first lattice columns for vertical support, the connecting line of the positions of the four first lattice columns forms a rectangle, the foundation pit lattice column body is located at the center of the rectangle, steel coupling beams for horizontal support are arranged between the adjacent two first lattice columns, and the device further comprises steel hangers and a positioning mechanism, the first lattice columns and the foundation pit lattice column body are both welded with steel hangers, and the positioning mechanism is used to position the steel hangers at the corresponding positions before the steel hangers are welded.The positioning mechanism which can be repeatedly installed and dismounted is used to fix the steel hangers on the lattice columns, the installation quality of the steel hangers is improved, the sudden settlement of the structure in the super-wide deep foundation pit support construction is avoided, and efficient and low-disturbance construction is realized under the premise of ensuring safety.

Description

Technical Field

[0001] This invention relates to the field of replacement device technology, specifically a replacement device for a grid column in an ultra-wide and deep foundation pit of a subway and its usage method. Background Technology

[0002] With the rapid development of urban rail transit construction, subway foundation pit engineering is gradually becoming deeper, larger, and more complex. Construction in densely populated urban areas often involves sensitive structures such as existing buildings, underground pipelines, and main traffic arteries around the foundation pit, placing extremely high demands on foundation pit deformation control. For example, consider a frame structure within a subway foundation pit with a three-layer steel support system. This steel support system is an assembly of steel supports, steel walers, connecting beams, and scissor braces. Below the three-layer steel support system is the foundation slab of the subway foundation pit, and above that is the top-level concrete support. Originally, a foundation pit lattice column body was installed on the foundation slab, passing through the three-layer steel support system and the concrete support from bottom to top. The lattice column includes four right-angle bars and several side plates. Gaps are left between adjacent right-angle bars, and side plates are welded equidistantly between adjacent right-angle bars. The side plates protrude from the outer surface of the right-angle bars.

[0003] During the subsequent construction of ultra-wide and deep foundation pit support, it is necessary to add elliptical columns. The original foundation pit grid column body conflicts with the newly added elliptical columns, so it is necessary to use grid column replacement technology to replace the foundation pit grid column body with elliptical columns.

[0004] During installation, it is necessary to hold the steel horn by hand or use steel wire to tie it to the lattice column before welding. Several steel wires need to be tied to one steel horn, which prolongs the welding and positioning time. The steel wires removed after welding cannot be reused, which increases the cost of welding and positioning. Summary of the Invention

[0005] The purpose of this invention is to provide a grid column replacement device for ultra-wide and deep foundation pits in subways and its usage method, so as to solve the problems raised in the prior art.

[0006] To achieve the above objectives, the present invention provides the following technical solution: a replacement device for a lattice column in an ultra-wide and deep foundation pit of a subway, comprising a foundation pit lattice column body and four first lattice columns for vertical support, the lines connecting the positions of the four first lattice columns forming a rectangle, the foundation pit lattice column body being located at the center of the rectangle, a steel connecting beam for lateral support being provided between two adjacent first lattice columns, and further comprising steel brackets and a positioning mechanism, wherein the steel brackets are welded to both the first lattice columns and the foundation pit lattice column body, and the positioning mechanism is used to position the steel brackets in the corresponding positions before welding them; The steel bracket includes steel bracket one and steel bracket two. The first lattice column is connected to the steel connecting beam through steel bracket one, and the foundation pit lattice column body is connected to the steel connecting beam through steel bracket two, thereby transferring the load of the foundation pit lattice column body. The positioning mechanism includes a hanging plate and a support shaft. The hanging plate is hung on the side plate of the first lattice column or the foundation pit lattice column body. The hanging plate is provided with a support shaft. A lifting component, a support component and a handle are sequentially sleeved on the support shaft. The inner ring surface of the handle is provided with an internal thread, and the outer ring surface of the support shaft is provided with an external thread. The internal thread of the handle engages with the external thread of the support shaft to adjust the position of the handle on the support shaft. The lifting member has a support member at the end away from the hanging plate. After the support member is spliced ​​with the support member at the end away from the hanging plate, the lifting member and the support member form a stable triangular support.

[0007] Furthermore, the lifting component includes a connecting rod one and a connecting rod two. One end of the connecting rod one is rotatably connected to the support shaft, and the other end of the connecting rod one is rotatably connected to the connecting rod two. The other end of the connecting rod two is provided with the support component. A main crown gear one is fixedly provided on the support shaft, and symmetrical secondary crown gear one and main crown gear two are fixedly provided on the connecting rod one along the axial direction of the support shaft. The support component includes a hollow sleeve rod and an inner rod. One end of the hollow sleeve rod is rotatably connected to the support shaft, and the other end of the hollow sleeve rod is fixedly fitted with a base. One end of the inner rod is inserted into the hollow sleeve rod, and the other end is provided with a hook for hooking the support component. A through hole is provided on the hollow sleeve rod corresponding to the base, and a pressure-bearing component that moves along its height direction is provided in the through hole. An extrusion block is rotatably provided on the base. A sliding groove is provided on the inner rod, and the pressure-bearing component is located between the extrusion block and the sliding groove. The extrusion block is provided with an adjacent long shaft end a and a short shaft end b. When the long shaft end a abuts against the pressure-bearing component, the inner rod cannot be moved. A handle is fixedly provided on the end of the extrusion block away from the long shaft end a. A secondary crown gear is provided on the hollow sleeve rod corresponding to the support shaft. When the secondary crown gear one meshes with the primary crown gear one, and the secondary crown gear two meshes with the primary crown gear two, the connecting rod one and the hollow sleeve rod cannot be rotated.

[0008] Furthermore, the pressure-bearing component includes an integral pressure-bearing block and a slider. Guide rods are symmetrically provided on both sides of the slider corresponding to the pressure-bearing block. A guide hole is provided in the base, and the guide rods are inserted into the guide hole. The slider fits into the groove.

[0009] Furthermore, the steel bracket includes an L-shaped steel plate and several ribs. The ribs are equidistantly distributed on the inner side of the L-shaped steel plate. Two receiving grooves are sequentially provided at both ends of the L-shaped steel plate along the height direction of the ribs. Several through holes are provided at the corresponding receiving grooves on the L-shaped steel plate. A slidably connected horizontal shaft is inserted through each of the through holes. A horizontal plate and a horizontal plate are respectively provided at both ends of the horizontal shaft. Both the L-shaped steel plate and the ribs are provided with cavities for the horizontal plate to move. The receiving grooves are used to place the horizontal plate, and the cavities are used to place the horizontal plate.

[0010] Furthermore, the two steel brackets and one end of the steel connecting beam form a group, and in the group, the two steel brackets are symmetrically distributed on the upper and lower sides of one end of the steel connecting beam.

[0011] Furthermore, the rib plate has an outward-facing groove at a location away from the storage slot, the support member includes a support shaft, a support block is slidably mounted on the support shaft, and a vertical plate is provided on the support block at one end near the lifting member along its length direction. The support block fixes the position of the steel bracket through the groove.

[0012] A method for using a grid column underpinning device for ultra-wide and deep foundation pits in subways, the method comprising: Step S1: Install four embedded parts using concrete on the base plate of the subway, remove the steel support device located on the third basement level, and install a first lattice column on each embedded part. The line connecting the locations of the four first lattice columns forms a rectangle, and the main body of the lattice column in the pit is located at the center of the rectangle. Step S2: After the top of the first lattice column passes through the gap in the steel support device of the second basement level, the top of the first lattice column is connected to the lattice column body of the foundation pit through welded steel brackets. Design the installation position of the steel bracket, use the positioning mechanism to position the steel bracket in the corresponding position, weld the steel bracket, and fix it by welding at least one steel connecting beam between two adjacent first lattice columns. The upper and lower sides of the end of the steel connecting beam are connected to the lattice column through the steel bracket. After welding is completed, remove the positioning mechanism. Step S3: Cut off the main body of the foundation pit grid column below the steel support device of the third basement level, and construct the side walls, elliptical columns and middle plate of the third basement level of the building; Step S4: Extend the first lattice column upwards to above the steel support device on the first basement level. Fix the steel bracket and steel connecting beam using the same method as in step S2. Transfer the load to the first lattice column. Remove the steel support device on the second basement level. Cut off the lattice column body below the steel support device on the second basement level. Construct the side walls, elliptical columns and middle plate of the second basement level. Step S5: Extend the first lattice column upwards to below the concrete support, fix the steel bracket and steel connecting beam using the same method as in step S2, remove the steel support device on the first basement floor, cut off the lattice column body below the concrete support, construct the side walls, elliptical columns and middle plate of the first basement floor, and cut off the first lattice column.

[0013] Furthermore, when the concrete strength reaches 80% of the design strength as described in step S1, the steel support device located on the third basement level is removed.

[0014] Furthermore, the process of using a positioning mechanism to position the steel bracket in the corresponding position as described in step S2 is as follows: Step F1: Take two positioning mechanisms and set them in their initial positions: Rotate handle one to move handle one outward, and pull the support and lifting parts outward in sequence to separate the secondary crown gear one from the main crown gear one, and the secondary crown gear two from the main crown gear two; The foundation pit lattice column support body and the first lattice column are both lattice columns. Find the side plate that is closest to the preset steel bracket installation position above it, and hang the hanging plate on the side plate; Step F2: Install the positioning mechanism on one side of the steel bracket: Take a steel bracket with one hand and pinch the support block with the other hand. Place the support block in the groove of the steel bracket. The vertical plate is located on the outside of the steel bracket. Press the steel bracket into the preset installation position. During the pressing process, the end of the second connecting rod will be pushed by the support and move. Hold the end of the second connecting rod with the other hand to support or pull the rotating connection between the first connecting rod and the second connecting rod. When the second connecting rod causes the end of the first connecting rod to rotate, the angle between the second connecting rod and the ground is limited, thereby adjusting the angle between the first connecting rod and the ground, and the angle between the first connecting rod and the second connecting rod. Step F3: After the steel bracket is in the preset installation position, turn the second handle outward. The second handle drives the extrusion block to rotate. The long shaft end a of the extrusion block moves away from the pressure-bearing part, and the short shaft end b of the extrusion block is on the pressure-bearing part. The short shaft end b cannot apply pressure to the pressure-bearing part. The extrusion block, the pressure-bearing part and the slide are loosely connected. Pull the inner rod outward so that the hook exceeds the support shaft. Turn the support upward so that the opening of the hook bites the support shaft. Then push the inner rod back into the hollow sleeve rod a bit so that the hook is hooked on the support shaft. Step F4: Reverse rotation of handle two causes the extrusion block to rotate in the opposite direction. The long shaft end a of the extrusion block abuts against the pressure-bearing component, and the extrusion block extrudes the pressure-bearing component. The pressure-bearing component extrudes the inner rod through the slide groove, making both the pressure-bearing component and the inner rod unable to move, and thus all three are fixed at the same time. Reverse rotation of handle one causes handle one to move closer to the main crown gear one. Handle one drives the support component and the lifting component to move closer to the crown gear one at the same time. The secondary crown gear one meshes with the main crown gear one again, and the secondary crown gear two meshes with the main crown gear two again, making it impossible to rotate the connecting rod one and the hollow sleeve rod. Step F5: Install the positioning mechanism on the other side of the steel bracket: First, insert the support block into the groove, and attach the vertical plate to the outside of the steel bracket. Then, insert the scraper onto the side plate on the other side of the lattice column. During the insertion process, the lifting component works on the same principle as in step F4, and the support component is fixed in the same way. The support component and the lifting component form a stable triangular support, and the steel bracket is pulled upward and inward simultaneously by the support component, so that the steel bracket is pre-fixed after it is attached to the lattice column. The installation method of the upright steel bracket and the inverted steel bracket is the same. The upright steel bracket is located above one end of the steel connecting beam, and the inverted steel bracket is located below one end of the steel connecting beam.

[0015] Furthermore, the process of welding the steel bracket in step S2 is as follows: When the steel bracket is placed in the preset installation position as described in steps G1 and F2, the first horizontal plate will contact the lattice column first and will be pushed back into the storage groove under the force. The upper and lower horizontal plates of a steel bracket are independent of each other. If the upper horizontal plate is fully inserted into the storage groove, the weld is at the connection between the upper part of the L-shaped steel plate and the lattice column; if the upper horizontal plate is not fully inserted into the storage groove, the weld is at the connection between the upper end of the horizontal plate and the lattice column; if the lower horizontal plate is fully inserted into the storage groove, the weld is at the connection between the lower end of the L-shaped steel plate and the lattice column; if the lower horizontal plate is not fully inserted into the storage groove, the weld is at the connection between the lower end of the horizontal plate and the lattice column. The connection points between the two sides of the horizontal plate and the L-shaped steel plate are always welded.

[0016] Compared with the prior art, the beneficial effects of the present invention are: This invention eliminates the need for manual support or wire binding during installation to position the steel horn on the lattice column. A reusable and removable positioning mechanism secures the steel horn to the column. A support member connects to the groove of the steel horn, ensuring both perpendicularity and parallelism to the ground during fixing, thus improving installation quality. Four first lattice columns are distributed along the four corners of a rectangle. The modular lattice column extensions, in conjunction with I-beam connecting beams, enable dynamic support and stepped replacement, allowing for a smooth transfer of the load from the lattice column body to the first lattice columns. This avoids sudden structural settlement during ultra-wide and deep foundation pit support construction, achieving efficient and low-disruption construction while ensuring safety. The two horizontal plates on the upper and lower parts of the L-shaped steel plate are self-adjusting based on the distance from the L-shaped steel plate to the lattice column, eliminating the need to pre-weld an iron plate to compensate for the distance and improving welding efficiency. Attached Figure Description

[0017] Figure 1 This is a cross-sectional view of the lattice column in this invention; Figure 2This is a schematic diagram of the lattice column in this invention from bottom to top; Figure 3 for Figure 2 Enlarged view of point A in the middle; Figure 4 This is a cross-sectional view of the hollow sleeve rod in this invention; Figure 5 for Figure 4 Enlarged view of point B in the middle; Figure 6 This is a bottom view of the steel bull horn in this invention; Figure 7 This is a cross-sectional view of the extrusion block in this invention; Figure 8 This is a top view showing the relative positions of the foundation pit lattice column body and the four first lattice columns in this invention; Figure 9 This is a construction diagram of the present invention; In the diagram: 1. Pit lattice column body; 2. First lattice column; 3. Steel connecting beam; 5. Steel bracket one; 6. Steel bracket one; 7. Hanging plate; 8. Support shaft; 9. Handle one; 10. Connecting rod one; 11. Connecting rod two; 12. Main crown gear one; 13. Secondary crown gear one; 14. Main crown gear two; 15. Secondary crown gear two; 16. Hollow sleeve rod; 17. Inner rod; 18. Base; 19. Hook; 20. Through hole one; 21. Extrusion block; 22. Slide groove; 23. Handle two; 24. Pressure block; 25. Sliding block; 26. Guide rod; 27. L-shaped steel plate; 28. Rib plate; 29. ​​Storage groove; 30. Horizontal shaft; 31. Horizontal plate one; 32. Horizontal plate two; 33. Groove; 34. Support shaft; 35. Support block; 36. Vertical plate; 40. Embedded parts; 41. Side walls; 42. Elliptical columns; 43. Middle plates; 44. Side plates; 45. Steel support devices; 46. Concrete supports. Detailed Implementation

[0018] 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.

[0019] See Figures 1-9 .

[0020] This invention provides a replacement device for a lattice column in an ultra-wide and deep foundation pit of a subway, comprising a foundation pit lattice column body 1 and four first lattice columns 2 for vertical support. The line connecting the positions of the four first lattice columns 2 forms a rectangle, with the foundation pit lattice column body 1 located at the center of the rectangle. A steel connecting beam 3 for lateral support is provided between two adjacent first lattice columns 2. The device also includes steel brackets and a positioning mechanism. The steel brackets are welded to both the first lattice columns 2 and the foundation pit lattice column body 1. Before welding the steel brackets, the positioning mechanism is used to position the steel brackets in the corresponding positions. The steel bracket includes steel bracket 1 5 and steel bracket 2 6. The first lattice column 2 is connected to the steel connecting beam 3 through steel bracket 1 5, and the foundation pit lattice column body 1 is connected to the steel connecting beam 3 through steel bracket 2 6, thereby transferring the load of the foundation pit lattice column body 1. The positioning mechanism includes a hanging plate 7 and a support shaft 8. The hanging plate 7 is hung on the side plate 44 of the first lattice column 2 or the foundation pit lattice column body 1. The hanging plate 7 is provided with a support shaft 8. A lifting component, a support component and a handle 9 are sequentially sleeved on the support shaft 8. The inner ring surface of the handle 9 is provided with an internal thread, and the outer ring surface of the support shaft 8 is provided with an external thread. The internal thread of the handle 9 meshes with the external thread of the support shaft 8 to adjust the position of the handle 9 on the support shaft 8. The lifting member has a support member at the end away from the hanging plate 7. After the support member is spliced ​​with the support member at the end away from the hanging plate 7, the lifting member and the support member form a stable triangular support.

[0021] Furthermore, the lifting component includes a first connecting rod 10 and a second connecting rod 11. One end of the first connecting rod 10 is rotatably connected to the support shaft 8, and the other end of the first connecting rod 10 is rotatably connected to the second connecting rod 11. The other end of the second connecting rod 11 is provided with the support component. A first main crown gear 12 is fixedly provided on the support shaft 8, and a symmetrical second secondary crown gear 13 and a second main crown gear 14 are fixedly provided on the first connecting rod 10 along the axial direction of the support shaft 8. The support includes a hollow sleeve rod 16 and an inner rod 17. One end of the hollow sleeve rod 16 is rotatably connected to the support shaft 8, and the other end of the hollow sleeve rod 16 is fixedly fitted with a base 18. One end of the inner rod 17 is inserted into the hollow sleeve rod 16, and the other end is provided with a hook 19 for hooking the support component. A through hole 20 is provided on the hollow sleeve rod 16 corresponding to the base 18. A pressure-bearing component that moves along its height direction is provided in the through hole 20. A pressing block 21 is rotatably provided on the base 18. A sliding groove 22 is provided on the inner rod 17. The pressure-bearing component is located between the extrusion block 21 and the slide groove 22. The extrusion block 21 has an adjacent long shaft end a and a short shaft end b. When the long shaft end a abuts against the pressure-bearing component, the inner rod 17 cannot be moved. A handle 23 is fixedly provided on the end of the extrusion block 21 away from the long shaft end a. A secondary crown gear 15 is provided on the hollow sleeve rod 16 at the corresponding position of the support shaft 8. When the secondary crown gear 13 meshes with the main crown gear 12, and the secondary crown gear 15 meshes with the main crown gear 14, the connecting rod 10 and the hollow sleeve rod 16 cannot be rotated.

[0022] Furthermore, the pressure-bearing component includes an integral pressure-bearing block 24 and a slider 25. Guide rods 26 are symmetrically provided on both sides of the slider 25 corresponding to the pressure-bearing block 24. A guide hole is provided in the base 18, and the guide rods 26 are inserted into the guide hole. The slider 25 is in contact with the slide groove 22.

[0023] Furthermore, the steel bracket includes an L-shaped steel plate 27 and several ribs 28. The ribs 28 are equidistantly distributed on the inner side of the L-shaped steel plate 27. Two receiving grooves 29 are sequentially provided at both ends of the L-shaped steel plate 27 along the height direction of the ribs 28. Several through holes are provided on the L-shaped steel plate 27 corresponding to the receiving grooves 29. A slidably connected horizontal shaft 30 passes through each of the through holes. A first horizontal plate 31 and a second horizontal plate 32 are respectively provided at both ends of the horizontal shaft 30. Both the L-shaped steel plate 27 and the ribs 28 have cavities for the movement of the second horizontal plate 32. The receiving grooves 29 are used to place the first horizontal plate 31, and the cavities are used to place the second horizontal plate 32. Before installation, the ribs 28 are welded to the inner side of the L-shaped steel plate 27.

[0024] Furthermore, the two steel brackets and one end of the steel connecting beam 3 form a group. In a group, the two steel brackets are symmetrically distributed on the upper and lower sides of one end of the steel connecting beam 3. When installing the steel brackets on the upper and lower sides of one end of the steel connecting beam 3, they can be pre-fixed by a positioning mechanism.

[0025] Furthermore, the rib plate 28 is provided with an outwardly opening groove 33 at a distance away from the storage groove 29. The support member includes a support shaft 34, and a support block 35 is slidably provided on the support shaft 34. A vertical plate 36 is provided on the support block 35 along its length direction near one end of the lifting member. The support block 35 fixes the position of the steel bracket through the groove 33.

[0026] Traditional support replacement techniques are prone to causing abrupt changes in retaining structure deformation and disturbance of surrounding soil during complex load transitions, making it difficult to meet the requirements for high-precision safety control. This invention discloses a method for using a grid column support replacement device for ultra-wide and deep foundation pits in subway systems. The method includes: Step S1: Install four embedded parts 40 using concrete on the base plate of the subway, remove the steel support device 45 located on the third basement level, and install a first lattice column 2 on each embedded part 40. The line connecting the locations of the four first lattice columns 2 forms a rectangle, and the main body 1 of the foundation pit lattice column is located at the center of the rectangle. Step S2: After the top of the first lattice column 2 passes through the gap of the steel support device 45 on the second basement floor, the top of the first lattice column 2 is connected to the lattice column body 1 of the foundation pit through the welded steel bracket 2 6. Design the installation position of the steel bracket, use the positioning mechanism to position the steel bracket in the corresponding position, weld the steel bracket, and fix it by welding at least one steel connecting beam 3 between two adjacent first lattice columns 2. The upper and lower sides of the end of the steel connecting beam 3 are connected to the lattice column through the steel bracket 5. After welding is completed, remove the positioning mechanism. Step S3: Cut off the foundation pit lattice column body 1 below the steel support device 45 of the third basement level, and construct the side wall 41, elliptical column 42 and middle plate 43 of the third basement level. Step S4: Extend the first lattice column 2 upwards to above the steel support device 45 on the first basement level, fix the steel bracket and steel connecting beam 3 using the same method as in step S2, transfer the load to the first lattice column 2, remove the steel support device 45 on the second basement level, cut off the foundation pit lattice column body 1 below the steel support device 45 on the second basement level, and construct the side wall 41, elliptical column 42 and middle plate 43 of the second basement level. Step S5: Extend the first lattice column 2 upwards to below the concrete support 46. Fix the steel bracket and steel connecting beam 3 using the same method as in step S2. Remove the steel support device 45 on the first basement level. Cut off the foundation pit lattice column body 1 below the concrete support 46. Construct the side wall 41, elliptical column 42, and middle plate 43 on the first basement level. Cut off the first lattice column 2. In this case, four first lattice columns 2 are distributed along the four corners of a rectangle. The modular lattice column extension cooperates with the connecting beam of the I-beam to achieve dynamic underpinning and stepped replacement of the support. This allows for the smooth transfer of the load of the foundation pit lattice column body 1 to the first lattice column 2, avoiding sudden settlement of the structure during the construction of ultra-wide and deep foundation pit support. This achieves efficient and low-disturbance construction while ensuring safety.

[0027] Furthermore, when the concrete strength reaches 80% of the design strength as described in step S1, the steel support device 45 located on the third basement level is removed.

[0028] Furthermore, the process of using a positioning mechanism to position the steel bracket in the corresponding position as described in step S2 is as follows: Step F1: Take two positioning mechanisms and set them in the initial position: Rotate handle 19 to move handle 19 outward, and pull the support and lifting parts outward in sequence, so that the secondary crown gear 13 separates from the main crown gear 12, and the secondary crown gear 25 separates from the main crown gear 24; The foundation pit lattice column support body and the first lattice column 2 are both lattice columns. Find the side plate 44 that is closest to the preset steel bracket installation position above it, and hang the hanging plate 7 on the side plate 44; Step F2: Install the positioning mechanism on the side of the steel bracket 5: Take a steel bracket with one hand and pinch the support block 35 with the other hand. Place the support block 35 in the groove 33 of the steel bracket. The vertical plate 36 is located on the outside of the steel bracket. Press the steel bracket into the preset installation position. During the pressing process, the connection between the support and the connecting rod 11 will rotate, and the end of the connecting rod 11 will move due to the push of the support. With the other hand, support or pull the end of the connecting rod 10 that is rotatably connected to the connecting rod 11. When the connecting rod 11 causes the end of the connecting rod 10 to rotate, the angle between the connecting rod 11 and the ground is limited, thereby adjusting the angle between the connecting rod 10 and the ground, and the angle between the connecting rod 10 and the connecting rod 11. Step F3: After the steel bracket is fitted into the preset installation position, turn the handle 23 outward. The handle 23 drives the extrusion block 21 to rotate. The long shaft end a of the extrusion block 21 moves away from the pressure-bearing part, and the short shaft end b of the extrusion block 21 is on the pressure-bearing part. The short shaft end b cannot apply pressure to the pressure-bearing part. The extrusion block 21, the pressure-bearing part and the slide 22 are loosely connected. Pull the inner rod 17 outward so that the hook 19 exceeds the support shaft 34. Turn the support upward so that the opening of the hook 19 bites the support shaft 34. Then push the inner rod 17 back into the hollow sleeve rod 16 a bit so that the hook 19 is hooked on the support shaft 34. Step F4: Reverse rotation of handle 23 causes the compression block 21 to rotate in the opposite direction. The long shaft end a of the compression block 21 abuts against the pressure member, and the compression block 21 compresses the pressure member. The pressure member compresses the inner rod 17 through the slide groove 22, making the pressure member and the inner rod 17 unable to move, and then all three are fixed at the same time. Reverse rotation of handle 9 causes handle 9 to move closer to the main crown gear 12. Handle 9 drives the support member and the lifting member to move closer to the crown gear 1 at the same time. The secondary crown gear 13 meshes with the main crown gear 12 again, and the secondary crown gear 15 meshes with the main crown gear 14 again, making it impossible to rotate the connecting rod 10 and the hollow sleeve rod 16. Step F5: Install the positioning mechanism on the other side of the steel bracket: First, insert the support block 35 into the groove 33, and attach the vertical plate 36 to the outside of the steel bracket. Then, insert the scraper onto the side plate 44 on the other side of the lattice column. During insertion, the lifting component operates on the same principle as in step F4, and the support component is fixed in the same way. The support component and the lifting component form a stable triangular support, and the steel bracket is pulled upward and inward simultaneously by the support component, so that the steel bracket is pre-fixed after being attached to the lattice column. The installation method for upright and inverted steel brackets is the same. The upright steel bracket is located above one end of the steel connecting beam 3, and the inverted steel bracket is located below one end of the steel connecting beam 3. When it is necessary to disassemble the positioning mechanism, the positioning mechanism needs to be adjusted to the initial state, and the handle 23 is rotated to release the pressure on the compressed part. Then, the positioning mechanism can be separated from the steel bracket by reversing the operation during installation.

[0029] During installation, there is no need to hold the steel horn or use steel wire to tie it to the lattice column. The positioning mechanism that can be repeatedly installed and disassembled is used to fix the steel horn to the lattice column. The support is connected to the groove 33 of the steel horn, which ensures that the steel horn is perpendicular to the ground and parallel to the ground during the fixing process, thus improving the installation quality of the steel horn.

[0030] Specifically, the process of welding the steel bracket in step S2 is as follows: When the steel bracket is placed in the preset installation position as described in steps G1 and F2, the horizontal plate 31 is the first to contact the lattice column and will be pushed back into the storage groove 29 under the action of force. The upper and lower horizontal plates 31 of a steel bracket are independent of each other. If the upper horizontal plate 31 is fully inserted into the receiving groove 29, the weld is the connection between the upper end of the L-shaped steel plate 27 and the lattice column; if the upper horizontal plate 31 is not fully inserted into the receiving groove 29, the weld is the connection between the upper end of the horizontal plate 31 and the lattice column; if the lower horizontal plate 31 is fully inserted into the receiving groove 29, the weld is the connection between the lower end of the L-shaped steel plate 27 and the lattice column; if the lower horizontal plate 31 is not fully inserted into the receiving groove 29, the weld is the connection between the lower end of the horizontal plate 31 and the lattice column. The connection between the side of the horizontal plate 32 and the L-shaped steel plate 27 is always welded. In the prior art, the side plate 44 of the lattice column protrudes from the outer surface of the right-angle rod, and the steel horn can be set at any height on the side of the lattice column. When the steel horn covers the edge of the side plate 44, one end of the steel horn will be in contact with the side plate 44, while the other end will have a gap with the right-angle rod, making it impossible to weld the steel horn from top to bottom. To compensate for this gap, an iron plate is welded to the right-angle rod, with the end of the iron plate spliced ​​to the side plate 44. Then, one end of the steel horn is welded to the side plate 44, and the other end is welded to the iron plate. This increases the welding process and reduces welding efficiency. In this case, the two horizontal plates 31 above and below the L-shaped steel plate 27 can self-adjust according to the distance from the L-shaped steel plate 27 to the lattice column, self-adjusting the spacing between the horizontal plates 31 and the corresponding positions of the lattice column. There is no need to pre-weld an iron plate to compensate for the distance between the L-shaped steel plate 27 and the lattice column, thus improving welding efficiency.

[0031] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

[0032] It should be noted that if the embodiments of the invention involve directional indicators (such as up and down), the directional indicators are only used to explain the relative positional relationship and movement of the components in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indicators will also change accordingly.

[0033] Furthermore, the meaning of "and / or" throughout the text includes three parallel solutions. Taking "A and / or B" as an example, it includes solution A, solution B, or a solution where both A and B are satisfied simultaneously. Additionally, if the embodiments of the invention involve descriptions such as "first," "second," etc., these descriptions are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include at least one of those features. Furthermore, "multiple" refers to two or more.

[0034] Furthermore, the technical solutions of the various embodiments can be combined with each other, but this must be based on the ability of a person skilled in the art to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be considered that such combination of technical solutions does not exist and is not within the scope of protection claimed by the invention.

Claims

1. A grid column replacement device for ultra-wide and deep foundation pits in subways, characterized in that: It includes a foundation pit lattice column body (1) and four first lattice columns (2) for vertical support. The line connecting the positions of the four first lattice columns (2) forms a rectangle. The foundation pit lattice column body (1) is located at the center of the rectangle. A steel connecting beam (3) for lateral support is provided between two adjacent first lattice columns (2). It also includes steel brackets and a positioning mechanism. The steel brackets are welded to both the first lattice columns (2) and the foundation pit lattice column body (1). Before welding the steel brackets, the positioning mechanism is used to position the steel brackets in the corresponding positions. The positioning mechanism includes a hanging plate (7) and a support shaft (8). The hanging plate (7) is hung on the side plate (44) of the first lattice column (2) or the foundation pit lattice column body (1). The hanging plate (7) is provided with a support shaft (8). The support shaft (8) is sequentially fitted with a lifting member, a support member and a handle (9). The inner ring surface of the handle (9) is provided with an internal thread, and the outer ring surface of the support shaft (8) is provided with an external thread. The internal thread of the handle (9) meshes with the external thread of the support shaft (8) to adjust the position of the handle (9) on the support shaft (8). The lifting member is provided with a support member at the end away from the hanging plate (7). After the support member is spliced ​​with the support member at the end away from the hanging plate (7), the lifting member and the support member form a stable triangular support. The lifting component includes a first connecting rod (10) and a second connecting rod (11). One end of the first connecting rod (10) is rotatably connected to the support shaft (8), and the other end of the first connecting rod (10) is rotatably connected to the second connecting rod (11). The other end of the second connecting rod (11) is provided with the support component. A first main crown gear (12) is fixedly provided on the support shaft (8), and a first secondary crown gear (13) and a second main crown gear (14) are fixedly provided on the first connecting rod (10) along the axial direction of the support shaft (8). The support includes a hollow sleeve rod (16) and an inner rod (17). One end of the hollow sleeve rod (16) is rotatably connected to the support shaft (8), and the other end of the hollow sleeve rod (16) is fixedly fitted with a base (18). One end of the inner rod (17) is inserted into the hollow sleeve rod (16), and the other end is provided with a hook (19), which is used to hook the support. A through hole (20) is provided on the hollow sleeve rod (16) at the corresponding position of the base (18). A pressure-bearing component that moves along its height direction is provided in the through hole (20). An extrusion block (21) is rotatably provided on the base (18), and a sliding groove (22) is provided on the inner rod (17). The pressure-bearing component is located between the extrusion block (21) and the slide groove (22). The extrusion block (21) is provided with adjacent long shaft end a and short shaft end b. When the long shaft end a abuts against the pressure-bearing component, the inner rod (17) cannot be moved. A handle two (23) is fixedly provided on one end of the extrusion block (21) away from the long shaft end a. A secondary crown gear two (15) is provided on the hollow sleeve rod (16) at the corresponding position of the support shaft (8). When the secondary crown gear one (13) meshes with the main crown gear one (12) and the secondary crown gear two (15) meshes with the main crown gear two (14), the connecting rod one (10) and the hollow sleeve rod (16) cannot be rotated. The pressure-bearing component includes an integral pressure-bearing block (24) and a slider (25). Guide rods (26) are symmetrically provided on both sides of the slider (25) corresponding to the pressure-bearing block (24). A guide hole is provided in the base (18), and the guide rods (26) are inserted into the guide hole. The slider (25) fits into the groove (22). The steel bracket includes an L-shaped steel plate (27) and several ribs (28). The ribs (28) are evenly distributed inside the L-shaped steel plate (27). Two storage slots (29) are provided at both ends of the L-shaped steel plate (27) along the height direction of the ribs (28). Several through holes are provided on the L-shaped steel plate (27) at the corresponding storage slots (29). A slidingly connected horizontal shaft (30) is provided through the through holes. A horizontal plate (31) and a horizontal plate (32) are provided at both ends of the horizontal shaft (30). Both the L-shaped steel plate (27) and the ribs (28) are provided with cavities for the horizontal plate (32) to move. The storage slots (29) are used to place the horizontal plate (31), and the cavities are used to place the horizontal plate (32). The steel bracket includes steel bracket one (5) and steel bracket two (6). The first lattice column (2) is connected to the steel connecting beam (3) through steel bracket one (5). The foundation pit lattice column body (1) is connected to the steel connecting beam (3) through steel bracket two (6) to transfer the load of the foundation pit lattice column body (1). The rib (28) has an outward-facing groove (33) located away from the storage groove (29). The support member includes a support shaft (34), on which a support block (35) is slidably provided. A vertical plate (36) is provided on the support block (35) along its length direction near one end of the lifting member. The support block (35) fixes the position of the steel bracket through the groove (33).

2. The method of using the interlocking column support device for ultra-wide and deep foundation pits in subways as described in claim 1, characterized in that: The method includes: Step S1: Install four embedded parts (40) on the base plate of the subway using concrete, remove the steel support device (45) located on the third basement level, and install a first lattice column (2) on each embedded part (40). The line connecting the locations of the four first lattice columns (2) forms a rectangle, and the lattice column body (1) of the foundation pit is located at the center of the rectangle. Step S2: After the top of the first lattice column (2) passes through the gap of the steel support device (45) on the second basement floor, the top of the first lattice column (2) is connected to the lattice column body (1) of the foundation pit through the welded steel bracket (6). Design the installation position of the steel bracket, use the positioning mechanism to position the steel bracket in the corresponding position, weld the steel bracket, and fix it by welding at least one steel connecting beam (3) between two adjacent first lattice columns (2). The upper and lower sides of the end of the steel connecting beam (3) are connected to the lattice column through the steel bracket (5). After welding is completed, remove the positioning mechanism. Step S3: Cut off the foundation pit grid column body (1) below the steel support device (45) of the third basement level, and construct the side wall (41), elliptical column (42) and middle plate (43) of the third basement level. Step S4: Extend the first lattice column (2) upwards to above the steel support device (45) on the first basement floor, fix the steel bracket and steel connecting beam (3) using the same method as in step S2, transfer the load to the first lattice column (2), remove the steel support device (45) on the second basement floor, cut off the lattice column body (1) below the steel support device (45) on the second basement floor, and construct the side wall (41), elliptical column (42) and middle plate (43) on the second basement floor. Step S5: Extend the first lattice column (2) upwards to below the concrete support (46), fix the steel bracket and steel connecting beam (3) in the same way as in step S2, remove the steel support device (45) on the first basement floor, cut off the lattice column body (1) below the concrete support (46), construct the side wall (41), elliptical column (42) and middle plate (43) on the first basement floor of the building; cut off the first lattice column (2).

3. The method of using the interlocking column replacement device for ultra-wide and deep foundation pits in subways according to claim 2, characterized in that: When the concrete strength reaches 80% of the design strength as described in step S1, the steel support device (45) located on the third basement level is removed.

4. The method of using the interlocking column replacement device for ultra-wide and deep foundation pits in subways according to claim 3, characterized in that: The process of using a positioning mechanism to position the steel bracket in the corresponding position as described in step S2 is as follows: Step F1: Take two positioning mechanisms and set them in the initial position: Turn handle one (9) to move handle one (9) outward, and pull the support and lifting parts outward in sequence so that the secondary crown gear one (13) separates from the main crown gear one (12) and the secondary crown gear two (15) separates from the main crown gear two (14); the foundation pit lattice column support body and the first lattice column (2) are both lattice columns. Find the side plate (44) that is closest to the installation position of the preset steel bracket and hang the hanging plate (7) on the side plate (44); Step F2: Install the positioning mechanism on the side of the steel bracket (5): Take a steel bracket with one hand and pinch the support block (35) with the other hand. Place the support block (35) in the groove (33) of the steel bracket. The vertical plate (36) is located on the outside of the steel bracket. Press the steel bracket into the preset installation position. During the pressing process, the end of the connecting rod (11) will be pushed by the support and move. The other hand holds the end of the connecting rod (10) and the connecting rod (11) for support or traction. When the connecting rod (11) drives the end of the connecting rod (10) to rotate, the angle between the connecting rod (11) and the ground is limited, thereby adjusting the angle between the connecting rod (10) and the ground. The angle between the connecting rod (10) and the connecting rod (11) is adjusted. Step F3: After the steel bracket is fitted into the preset installation position, turn the handle two (23) outward. The handle two (23) drives the extrusion block (21) to rotate. The long shaft end a of the extrusion block (21) moves away from the pressure-bearing part, and the short shaft end b of the extrusion block (21) is located on the pressure-bearing part. The short shaft end b cannot apply pressure to the pressure-bearing part. The extrusion block (21), the pressure-bearing part and the slide groove (22) are loosely connected. Pull the inner rod (17) outward so that the hook (19) exceeds the support shaft (34). Rotate the support upward so that the opening of the hook (19) bites the support shaft (34). Then push the inner rod (17) back into the hollow sleeve rod (16) a bit so that the hook (19) hangs on the support shaft (34). Step F4: Rotate handle two (23) in the reverse direction. Handle two (23) drives the extrusion block (21) to rotate in the reverse direction. The long shaft end a of the extrusion block (21) abuts against the pressure member. The extrusion block (21) extrudes the pressure member. The pressure member extrudes the inner rod (17) through the slide groove (22), so that the pressure member and the inner rod (17) cannot move. Then all three are fixed at the same time. Rotate handle one (9) in the reverse direction. Handle one (9) moves closer to the main crown gear one (12). Handle one (9) drives the support member and the lifting member to move closer to the crown gear one at the same time. The secondary crown gear one (13) meshes with the main crown gear one (12) again. The secondary crown gear two (15) meshes with the main crown gear two (14) again. The connecting rod one (10) and the hollow sleeve rod (16) cannot be rotated. Step F5, Install the positioning mechanism on the other side of the steel bracket: First, insert the support block (35) into the groove (33), and the vertical plate (36) is attached to the outside of the steel bracket. Then, insert the scraper into the side plate (44) on the other side of the lattice column. During the insertion process, the lifting part is used in the same way as in step F4, and the support part is fixed in the same way. The support part and the lifting part form a stable triangular support, and the steel bracket is pulled upward and inward by the support part at the same time, so that the steel bracket is attached to the lattice column and pre-fixed. The installation method of the upright steel bracket and the inverted steel bracket is the same. The upright steel bracket is located above one end of the steel connecting beam (3), and the inverted steel bracket is located below one end of the steel connecting beam (3).

5. The method of using the subway ultra-wide and deep foundation pit grid column replacement device according to claim 4, characterized in that: The process of welding the steel bracket in step S2 is as follows: When the steel bracket is pressed into the preset installation position as described in steps G1 and F2, the first horizontal plate (31) first contacts the lattice column and is pushed back into the storage groove (29) under the action of force. The upper and lower horizontal plates (31) of a steel bracket are independent of each other. If the upper horizontal plate (31) is fully inserted into the receiving groove (29), the weld is the connection between the upper end of the L-shaped steel plate (27) and the lattice column; if the upper horizontal plate (31) is not fully inserted into the receiving groove (29), the weld is the connection between the upper end of the horizontal plate (31) and the lattice column; if the lower horizontal plate (31) is fully inserted into the receiving groove (29), the weld is the connection between the lower end of the L-shaped steel plate (27) and the lattice column; if the lower horizontal plate (31) is not fully inserted into the receiving groove (29), the weld is the connection between the lower end of the horizontal plate (31) and the lattice column. The connection between the side of the horizontal plate (32) and the L-shaped steel plate (27) is always welded.

Images