Outdoor pre-buried group pipe anti-floating positioning construction method and positioning tool thereof

Abstract

The present application relates to the field of building construction technology, specifically to an outdoor pre-embedded group pipe anti-floating positioning construction method and positioning tool, comprising the following steps: step one: punching a plurality of waste steel bars around the cushion layer, and connecting each waste steel bar to each other by spot welding to form an integral rigid frame; step two: prefabricating a positioning plate, a plurality of circular through holes are formed on the positioning plate, and the positions of the through holes are consistent with the design arrangement positions of the group pipe; step three: respectively passing each pipe to be buried through the corresponding circular through hole on the positioning plate; step four: adjusting the position and elevation of the positioning plate, so that all pipes simultaneously reach the overall arrangement of the design requirements; step five: using finished plastic pipe clamps to connect and fix adjacent pipes to each other, and lock the relative spacing between the pipes; the present application forms a rigid anti-floating system anchored with the soil body around the cushion layer by spot welding the waste steel bar frame and the group pipe as a whole.

Description

Technical Field

[0001] This invention relates to the field of building construction technology, specifically to an anti-buoyancy positioning construction method and positioning tooling for outdoor pre-embedded pipe groups. Background Technology

[0002] In municipal, power, and telecommunications outdoor pipeline projects, it is often necessary to pre-bury multiple SC galvanized steel pipes (such as SC200 and SC100), and they are often buried in groups (e.g., 20 or 36 pipes per group). Traditional construction methods mainly rely on workers to pull lines, visually inspect, and adjust the position of each pipe individually, which has the following drawbacks: 1. Poor spacing control: With a large number of pipes, errors accumulate when adjusting each pipe individually, making it difficult to ensure consistent net spacing between pipes, especially with obvious deviations in the middle section of the pipes; 2. Lower pipes are prone to deviation: Without effective constraints, the lower pipes are prone to deviating from the design elevation and plane position due to gravity and installation disturbances. 3. Severe floating during concrete pouring: When the concrete is poured, the pipes that are not effectively connected to the foundation or anti-buoyancy structure are subjected to the buoyancy of the concrete and float up as a whole, resulting in pipe misalignment, insufficient protective layer thickness, or even failure to meet acceptance requirements. 4. Inefficient: Each pipe requires repeated adjustments, measurements, and temporary fixing, which consumes a lot of manpower and time, and requires a high level of technical skills from workers.

[0003] Existing improvement solutions have shortcomings: some use permanent plastic pipe clamps to fix the spacing between pipes, but this cannot solve the problem of the overall pipe floating; some use reinforcing bars in the bedding layer and weld them to the pipes, but this is costly and damages the integrity of the bedding layer; some use disposable wooden templates or plastic positioners, but these cannot be reused, resulting in waste of materials.

[0004] Therefore, we propose an anti-buoyancy positioning construction method and positioning tooling for outdoor pre-embedded pipe groups. Summary of the Invention

[0005] To address the shortcomings of existing technologies, this solution provides a construction method and tooling that can ensure precise positioning of the pipe group, effectively resist the buoyancy of concrete pouring, and is low-cost and reusable.

[0006] This application provides a method for anti-buoyancy positioning construction of outdoor pre-embedded pipe groups, including the following steps: Step 1: Drive multiple scrap steel bars into the perimeter of the foundation layer and spot weld them together to form a rigid frame. Step 2: Prefabricate a positioning plate with multiple circular through holes, the positions of which are consistent with the design layout of the group of pipes; Step 3: Pass each pipe to be buried through the corresponding circular through hole on the positioning plate; Step 4: Adjust the position and elevation of the positioning plate to ensure that all pipes are arranged in the overall layout required by the design. Step 5: Use prefabricated plastic pipe clamps to connect and fix adjacent pipes to each other, locking the relative distance between the pipes; Step Six: Spot weld each pipe to the rigid frame described in Step One. This spot welding connection is used to resist the buoyancy generated during concrete pouring and to maintain the overall stability of the pipe group. Step 7: Slide the positioning plate out along the axial direction of the pipe. At this time, the pipe is held in place by pipe clamps to maintain the distance between pipes and by spot welding to maintain the overall position with the rigid frame. Step 8: Transfer the positioning plate to the next group of tubes and repeat steps 2 to 7; Step 9: Pour concrete to permanently embed the plastic pipe clamps, scrap steel frame, and pipes in the concrete.

[0007] Furthermore, the diameter of the scrap steel bars mentioned in step one shall not be less than 10mm, the depth to which they are driven into the soil surrounding the foundation layer shall not be less than 25cm, and the exposed height shall be determined according to the design elevation of the group pipe.

[0008] Furthermore, the positioning plate mentioned in step two is a steel plate with a thickness of 8-20mm, and the diameter of the circular through hole is 2-6mm larger than the outer diameter of the pipe.

[0009] Furthermore, the positioning plate described in step two is provided with handles or lifting rings on its edge for easy axial pulling.

[0010] Furthermore, the spot welding connection between the pipe and the rigid frame described in step six is ​​set every 1-2 meters along the length of the pipe.

[0011] Furthermore, the positioning plate is not rust-proofed after being pulled out, and the weld joints do not require additional rust prevention because they are eventually covered by concrete.

[0012] An outdoor pre-embedded pipe positioning fixture includes a positioning plate with multiple circular through holes arranged according to the design layout and center-to-center distance of the pre-embedded pipes. The diameter of each circular through hole is larger than the outer diameter of the pipe to be inserted, allowing each pipe to slide through the corresponding circular through hole. In use, all pipes are simultaneously inserted into the corresponding through holes. After the pipes are fixed together by prefabricated plastic pipe clamps and fixed to a rigid frame made of scrap steel bars, the positioning plate can be slidably pulled out along the axial direction of the pipes and reused for the next group of pipes.

[0013] Furthermore, the positioning plate is made of steel plate with a thickness of 8-20mm and a hole diameter that is 2-6mm larger than the outer diameter of the pipe.

[0014] Furthermore, the positioning plate is provided with handles or lifting rings at both ends in the pulling direction.

[0015] Furthermore, the surface of the positioning plate has no anti-rust coating.

[0016] The technical solution provided in this application has at least the following technical effects or advantages: 1. The invention provides reliable anti-buoyancy protection: By spot welding the scrap steel frame to the pipe group as a whole, a rigid anti-buoyancy system anchored to the surrounding soil of the cushion layer is formed. Field tests show that without this method, the pipe group floats by 15-20mm, while with this method, the float is close to zero (<2mm). 2. The present invention has high positioning accuracy: the positioning plate constrains all pipes at one time, the pipe clamp locks the spacing between pipes, and the deviation of the group pipe spacing can be reduced from ±15mm in the traditional method to within ±3mm; 3. The invention has extremely low cost: the anti-buoyancy frame uses scrap steel bars from construction sites, eliminating the need to purchase new materials; the positioning plate can be reused hundreds of times, resulting in extremely low cost amortization. 4. This invention does not damage the subgrade: The frame is independently driven into the soil around the subgrade, without the need for rebar or pre-embedding on the subgrade, making construction flexible and without damaging the completed subgrade. 5. This invention has high construction efficiency: it completes the initial positioning of all pipes at one time, which shortens the installation time by about 70% compared to adjusting one pipe at a time, and does not rely on skilled workers; 6. Simplified process: Since the weld points and pipes are ultimately encased in concrete, the alkaline environment of the concrete provides corrosion protection, eliminating the need for rust prevention treatment of the weld points or positioning plates, thus saving materials and labor time. 7. Green and environmentally friendly: Waste steel bars are reused, reducing construction waste. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the positioning plate structure in this application.

[0018] In the diagram: 1-Concrete covering; 2-Concrete foundation; 3-Positioning plate; 4-Steel pipe; 5-Scrap steel bars. Detailed Implementation

[0019] This application discloses an anti-buoyancy positioning construction method and positioning fixture for outdoor pre-buried pipe groups. The technical solutions of the embodiments of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this invention, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the scope of protection of this invention.

[0020] To better understand the above technical solution, the following will provide a detailed explanation of the above technical solution in conjunction with the accompanying drawings and specific implementation methods.

[0021] Please see Figure 1 This implementation case is applicable to underground integrated pipe gallery, outdoor basement roof slab pre-embedding, and park integrated pipe network pre-embedding scenarios. It uses a single group of 20 SC200 hot-dip galvanized welded steel pipes as the construction unit, with the pipes arranged in 4 rows × 5 columns. The horizontal and vertical spacing between the pipe centers is 300mm, and the nominal outer diameter of the steel pipe is 219mm. The foundation cushion layer is a C15 plain concrete cushion layer 2 with a thickness of 100mm. The pre-embedding of the group pipes can only be carried out after the cushion layer construction is completed and the strength reaches 70%. The site is equipped with construction tools such as AC electric welding machine, hammer, tape measure, level, crowbar, and hoisting rope. The main construction consumables are scrap threaded steel bars, Q235 steel plates, and prefabricated rigid plastic pipe clamps.

[0022] This solution addresses the pain points of traditional pre-embedded multi-pipe systems: large spacing deviations in the arrangement of multiple pipes, pipe floating and displacement during concrete pouring, high material costs due to the one-time use of prefabricated templates, cumbersome pipe positioning and correction procedures, and insufficient space for subsequent pipe wiring.

[0023] And before construction; Pre-treatment of scrap steel bars for the anti-buoyancy frame: HRB400 threaded steel bars from on-site demolition are selected. Vertical anti-buoyancy reinforcement bars are uniformly made of scrap steel bars with a diameter of 12mm and a total length of 500mm per bar. Horizontal connecting bars are made of scrap threaded steel bars with a diameter of 10mm. All scrap steel bars are manually cleaned beforehand to remove surface rust and attached concrete lumps, and burrs are bent and ground smooth to ensure clean welding contact surfaces and improve spot weld connection strength. Prefabrication of pull-out reusable positioning plate 3: Plate selection: 12mm thick Q235 carbon steel plate is selected, and the cutting size is 1500mm (length) × 1200mm (width). The steel plate surface has no anti-rust paint and no galvanized coating to reduce the frictional resistance with the outer wall of the steel pipe 4 during the pulling process. The plate surface is reserved for cutting. After cutting, the burrs on the four sides of the plate are ground to prevent scratching the galvanized steel pipe (4) anti-corrosion layer.

[0024] Hole drilling: Drill holes in a 4x5 matrix arrangement, with a horizontal hole center-to-center distance of 300mm and a vertical hole center-to-center distance of 300mm, totaling 20 circular through holes; the inner diameter of each hole is 223mm, compared to the outer diameter of SC200 steel pipe 4 (219mm), a 2mm sliding clearance is reserved on each side to ensure that the steel pipe 4 can be freely inserted and the plate can be smoothly axially removed later. After drilling, the sharp edges of the inner wall of the through holes are ground to avoid cutting the galvanized layer of the steel pipe 4.

[0025] Processing of pull-out auxiliary structure: Two semi-circular handles made of Φ16 round steel are symmetrically welded to the two sides of the positioning plate 3 along its length. The exposed length of the handles is 80mm, and the welding is fully reinforced. A single person can pull out the plate by holding the handle. When multiple sets of pipes are being constructed, they can be used with rope hoisting and traction, which is suitable for long-distance plate pulling operations.

[0026] Prefabrication acceptance: After processing, check the hole size and plate flatness. If there is no warping or deformation and the hole deviation is ≤1mm, it is considered qualified. Positioning plate 3 does not need to be coated with anti-rust material. After construction, it can be stored in the open air and reused repeatedly.

[0027] Complete construction steps for outdoor pre-embedded pipe anti-buoyancy positioning Step 1: On-site erection of rigid anti-buoyancy steel frame Point layout: On the hardened C15 concrete foundation 2, use a chalk line to mark the overall outer contour of a single group of 20 pipes. Mark the vertical reinforcement points every 1.5m along the two outer edges of the pipe length.

[0028] Vertical reinforcement bar insertion: 5 vertical scrap steel bars are manually inserted using a sledgehammer. Each steel bar is 500mm long, with 300mm driven vertically into the subgrade soil below the foundation layer, and the remaining 200mm protruding above the foundation layer surface. The verticality deviation of the steel bar insertion is controlled within 3°, and the top surface elevation of all vertical reinforcement bars is uniform.

[0029] Integral spot welding: 10mm diameter scrap steel bars are used as transverse connecting bars. The bars are arranged along the length of the pipeline. All vertical bars are exposed at the top and lapped together in pairs. The lap weld length is not less than 30mm and the weld is continuous and full. Two transverse connecting bars are set up to form a double-layer grid rigid frame, which connects the scattered vertical bars into a whole and realizes multi-point anti-buoyancy constraint of the entire pipeline.

[0030] Step 2: Installation of positioning plate 3 and pre-installation of pipes The prefabricated positioning plate 3 is hoisted to the starting end of the pipeline and placed horizontally above the padding layer. Twenty SC200 galvanized steel pipes 4 are then aligned one end with the corresponding circular through hole of the positioning plate 3 and inserted into the plate from the same side. The insertion depth of the steel pipes 4 is controlled at 800mm to ensure that the ends of each steel pipe 4 pass through the positioning plate 3 synchronously. The steel pipes 4 can slide freely back and forth in the through hole without jamming or squeezing.

[0031] Step 3: Overall Elevation and Planar Position Correction Planar alignment: The positioning plate 3 is manually pushed, which simultaneously drives the 20 steel pipes 4 to move as a whole. Combined with the ink line outline of the padding layer, the overall left and right and front and back plane positions of the pipeline are corrected to ensure that the outer contour of the matrix arrangement is completely coincident with the design edge line.

[0032] Elevation leveling: Place cement mortar blocks of the same thickness at the bottom of each steel pipe 4, and re-measure the elevation of the upper surface of the pipe with a level. Adjust the height of the blocks one by one to make the top elevation of all 20 steel pipes 4 uniform, with the elevation error controlled within ±2mm. During the correction process, the positioning plate 3 moves synchronously with the pipe to maintain the relative spacing of all pipes.

[0033] Step 4: Secure the relative spacing between pipes with finished plastic pipe clamps. After the pipeline plane and elevation are corrected, prefabricated rigid plastic pipe clamps are installed at the gaps between two adjacent steel pipes 4 on the inner side of the positioning plate 3. The pipe clamps wrap around the outer walls of the two steel pipes 4 and lock them in place. An additional set of pipe clamps is added every 2m along the pipeline axis. All adjacent pipelines in the transverse and longitudinal directions are connected with pipe clamps. The rigid constraint of the pipe clamps locks the standard center distance of 300mm, eliminating the risk of pipeline misalignment and squeezing displacement in the later stage. The plastic pipe clamps are non-metallic components and are permanently retained inside the concrete after pouring, without causing electrochemical corrosion of the steel pipes 4.

[0034] Step 5: Spot weld the pipe to the rigid frame for anti-buoyancy fixation. Welding point arrangement: Three spot welding points are evenly set along the length of each SC200 steel pipe 4, namely the beginning end of the pipe, the middle section of the pipe, and the end end of the pipe; the single pipe is lapped and spot welded to the vertical / horizontal scrap steel reinforcement 5 frame, with a weld length of 30mm.

[0035] Welding construction: A small on-site AC welding machine is used, J422 low carbon welding rods are selected, the welding current is reduced, and spot welding process is adopted to avoid high temperature and long-term burning that damages the galvanized anti-corrosion layer on the outer wall of steel pipe 4; the welding point rigidly connects steel pipe 4 to the steel frame, and a single welding point can withstand about 50kg of concrete buoyancy. The whole group of multiple points forms an overall anti-buoyancy system, which completely prevents the pipeline from floating and drifting during the pouring stage.

[0036] Simple post-weld treatment: Weld slag is manually removed, no need to apply anti-rust paint, and then the entire weld is wrapped in concrete. The alkaline environment of the concrete can isolate air and moisture, so there is no risk of corrosion at the weld joint.

[0037] Step 6: Axially remove positioning plate 3 to enable repeated tooling turnover. After all pipe clamps are locked and all anti-floating spot welds on the pipes have passed inspection, two construction workers hold the semi-circular handles at both ends of the positioning plate 3 and slowly pull the plate outward along the axial direction of the steel pipe 4. Because the pipe clamps have fixed the relative positions of all pipes and the steel frame has locked the overall coordinates of the pipes, the steel pipe 4 does not shift, flip, or float during the plate pulling process.

[0038] After the positioning plate 3 is completely removed, the dust and mortar residue attached to the through holes on the plate surface are manually cleaned. After checking that the plate surface and through holes are free from deformation and cracks, it can be transferred to the next adjacent group of pipe construction area and the pipe laying and positioning process is carried out in a cycle. In this project, a single positioning plate 3 can be reused a total of 50 times. There is no obvious deformation in the hole position and plate size, which meets the needs of continuous construction of multiple pipelines.

[0039] Step 7: Multi-group pipe circulation construction Repeat steps two through six to complete the positioning and anti-buoyancy reinforcement of the remaining pre-buried pipe groups in this section. After all pipeline units are completed, check the plane position, elevation, and spacing of all pipelines and make a record of the acceptance of concealed works.

[0040] Step 8: Concrete is poured and formed as a whole. After the concealed acceptance is qualified, the structural concrete pouring operation shall be carried out. The concrete shall be poured slowly in layers, and the vibrator shall be vibrated evenly along the gap between the pipes. It is forbidden to forcefully hit the steel pipe wall with the vibrator. After the concrete is poured, the concrete shall completely cover the SC200 steel pipe, the finished plastic pipe clamp, the scrap steel bar rigid anti-buoyancy frame, and all welding points.

[0041] After the concrete hardens and solidifies, the internal steel bars, pipe clamps, and welds completely isolate the external water and oxygen, eliminating the need for subsequent anti-corrosion repairs and permanently fixing the layout of the pre-embedded pipe group.

[0042] In this application, the main body of the tooling is a reusable pull-out steel plate positioning plate 3. The plate body has corresponding through holes opened according to the designed group pipe matrix. The diameter of the through holes is larger than the outer diameter of the pipe and a sliding gap is reserved. Unlike the traditional disposable wooden mold and foam positioning plate 3, this tooling has high steel strength and can be used repeatedly across multiple construction sections, which greatly reduces the cost of construction materials.

[0043] Tooling dimensions: Plate thickness 12mm (general range 8~20mm, 8mm thin plate for small pipe diameter, 20mm thick steel plate for large diameter heavy pipe), 2~6mm sliding clearance reserved on one side of the through hole, suitable for galvanized steel pipes of different outer diameters, PE pipes, PVC power protection pipes.

[0044] Turnover auxiliary structure: Semi-circular handles / lifting rings are welded to both ends of the plate, which can be manually pulled out by one person or mechanically lifted and pulled, and is suitable for short and long distance plate pulling conditions, avoiding the plate tilting and jamming the pipe when pulling out.

[0045] The design of the plate surface without anti-rust coating: the original oxide scale is retained on the surface of the steel plate, without paint or zinc plating layer. The coating will not fall off and stick to the steel pipe during the pulling process, reducing the cleaning process. Even if the tooling is stored in the open and produces slight surface rust, it will not affect the positioning accuracy when it is used again for pipe pulling. After the construction is completed, the rusted plate can be recycled and reused as steel.

[0046] Obviously, those skilled in the art can make various modifications and variations to this invention without departing from its spirit and scope. Therefore, if these modifications and variations fall within the scope of the claims of this invention and their equivalents, this invention also intends to include these modifications and variations.

[0047] The above description is merely a preferred embodiment of the present application, but the scope of protection of the present application is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present application, based on the technical solution and concept of the present application, should be covered within the scope of protection of the present application.

Claims

1. A method for anti-buoyancy positioning construction of outdoor pre-embedded pipe groups, characterized in that, Includes the following steps: Step 1: Drive multiple scrap steel bars (5) around the foundation layer and spot weld them together to form an integral rigid frame; Step 2: Prefabricate a positioning plate (3), on which multiple circular through holes are opened, and the positions of the through holes are consistent with the design layout of the group pipes; Step 3: Pass each pipe to be buried through the corresponding circular through hole on the positioning plate (3); Step 4: Adjust the position and elevation of the positioning plate (3) so that all pipes can simultaneously achieve the overall layout required by the design. Step 5: Use prefabricated plastic pipe clamps to connect and fix adjacent pipes to each other, locking the relative distance between the pipes; Step Six: Spot weld each pipe to the rigid frame described in Step One. This spot welding connection is used to resist the buoyancy generated during concrete pouring and to maintain the overall stability of the pipe group. Step 7: Slide the positioning plate (3) out along the axial direction of the pipe. At this time, the pipe has been kept in place by pipe clamps to maintain the distance between pipes and by spot welding to maintain the overall position with the rigid frame. Step 8: Transfer the positioning plate (3) to the next group of tubes and repeat steps 2 to 7; Step 9: Pour concrete to permanently embed the plastic pipe clamps, scrap steel bars (5) frame and pipes in the concrete.

2. The method according to claim 1, characterized in that: The diameter of the scrap steel bar (5) mentioned in step one shall not be less than 10mm, the depth of driving it into the soil around the cushion layer shall not be less than 25cm, and the exposed height shall be determined according to the design elevation of the group pipe.

3. The method according to claim 1, characterized in that: The positioning plate (3) mentioned in step two is a steel plate with a thickness of 8-20mm, and the diameter of the circular through hole is 2-6mm larger than the outer diameter of the pipe.

4. The method according to claim 1, characterized in that: The positioning plate (3) described in step two has handles or lifting rings on its edge for easy axial pulling.

5. The method according to claim 1, characterized in that: The spot welding connection between the pipe and the rigid frame described in step six is ​​set every 1-2 meters along the length of the pipe.

6. The method according to claim 1, characterized in that: The positioning plate (3) is not rust-proofed after being pulled out, and the weld points do not require additional rust prevention because they are eventually covered by concrete.

7. An outdoor pre-embedded pipe positioning fixture for implementing the method of any one of claims 1 to 6, characterized in that: It includes a positioning plate (3), on which multiple circular through holes are provided, and the circular through holes are arranged according to the design layout and design center distance of the pre-embedded group pipes; The diameter of the circular through hole is larger than the outer diameter of the pipe to be inserted, so that each pipe can slide through the corresponding circular through hole. When in use, the positioning plate (3) inserts all pipes into the corresponding through holes at the same time. After the pipes are fixed together by finished plastic pipe clamps and the pipes are fixed to the rigid frame made of scrap steel bars (5) by spot welding, the positioning plate (3) can slide out along the axial direction of the pipes and be reused for the next group of pipes.

8. The outdoor pre-embedded pipe positioning fixture according to claim 7, characterized in that: The positioning plate (3) is a steel plate with a thickness of 8-20mm and a hole diameter that is 2-6mm larger than the outer diameter of the pipe.

9. The outdoor pre-embedded pipe positioning fixture according to claim 7, characterized in that: The positioning plate (3) is provided with handles or lifting rings at both ends in the pulling direction.

10. The outdoor pre-embedded pipe positioning fixture according to claim 7, characterized in that: The surface of the positioning plate (3) has no anti-rust coating.

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