A construction technique for precise elevation positioning of cast-in-place concrete piles
By using the over-pouring detector and the fuse controller in combination, the elevation of the cast-in-place piles can be accurately controlled, the over-pouring problem can be solved, concrete materials and construction costs can be saved, and construction safety can be improved.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- CHINA CHEM SOUTH CONSTR INVESTMENT (JIANGXI) CO LTD
- Filing Date
- 2023-03-31
- Publication Date
- 2026-05-26
AI Technical Summary
In existing bored pile construction, over-grouting distance is difficult to control, resulting in increased concrete consumption, high construction costs, and safety hazards.
By using an over-pouring detector and a fuse controller in conjunction with steel pipelines and wire loops, the elevation of the cast-in-place piles is automatically controlled to ensure accurate positioning and avoid over-pouring.
It has achieved precise control of the elevation of cast-in-place piles, reduced concrete consumption, lowered construction costs, shortened the construction period, and improved construction safety.
Smart Images
Figure CN117403629B_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of cast-in-place pile construction technology, and in particular to a construction process for precise elevation positioning of cast-in-place concrete piles. Background Technology
[0002] Drilled cast-in-place piles are typically made of cast-in-place reinforced concrete. They offer advantages such as vibration-free construction, no soil displacement, low noise, and suitability for use in densely built-up urban areas. The drilling and grouting technology used in their construction has been widely applied in building engineering and is currently the most common type of pile foundation. Existing research indicates that drilled cast-in-place piles possess high safety and strong stability. The concrete grout penetrates deep into the soil layer, tightly bonding the soil with the pile body, thus making the foundation more solid and reliable. Simultaneously, the piles effectively control foundation settlement, thereby compacting the soil. Drilled cast-in-place piles provide good penetration, compaction, and splitting effects on the soil layer, and the interaction among these three factors further stabilizes the soil.
[0003] However, the construction environment for bored piles is typically extremely harsh, and the construction process is inevitably affected by numerous factors. During pile foundation construction, after the piles reach the design elevation, over-pouring is usually required over a certain distance, often exceeding 0.8m and sometimes even reaching 1.0m. This over-pouring distance is usually controlled by the on-site construction personnel. Due to the large number of bored piles on-site and the varying skill levels of the construction personnel, the final over-pouring varies greatly. Furthermore, the presence of over-pouring concrete not only increases the amount of concrete used but also increases the difficulty and danger of breaking up the over-pouring pile heads, thus increasing construction costs and safety hazards.
[0004] Regarding the aforementioned technologies, this invention proposes a construction process for precise elevation positioning of cast-in-place concrete piles. If the elevation of the cast-in-place pile can be controlled within 0.1m above the design elevation, not only can the over-pouring height be controlled, but materials can also be saved, and the pile head breaking can be avoided if the elevation exceeds the design elevation. Summary of the Invention
[0005] To overcome the aforementioned deficiencies of the prior art, this invention provides a construction process for precise elevation positioning of cast-in-place concrete piles, which solves the problem of uncontrollable over-pouring in existing bored cast-in-place piles, saves concrete materials, avoids the subsequent construction work of breaking the pile head due to over-pouring, saves manpower to a certain extent, shortens the construction period of cast-in-place piles, and saves construction costs.
[0006] To achieve the above objectives, the technical solution adopted by the present invention is as follows:
[0007] A construction process for precise elevation positioning of cast-in-place concrete piles includes the following steps:
[0008] S1. Setting up the platform: First, on the leveled site soil, after determining the specific location of the cast-in-place pile according to the design requirements, a steel cage with longitudinal reinforcement is embedded in the hole in the site soil according to the hole-forming process of the bored cast-in-place pile. A pad is laid around the site soil of the bored cast-in-place pile according to the designed location of the bored cast-in-place pile, and a pad block is set on top of the pad. An operating platform is set on top of the pad block.
[0009] S2. Install the over-grouting detection instrument for cast-in-place piles: Install two sets of springs symmetrically on the operating platform. Use elastic rubber ropes to fix the upper hooks of the steel pipes at the springs on the operating platform to complete the installation of the two sets of steel pipes. Use fusible gaskets to fix the wire loops at the longitudinal reinforcement of the reinforcing cage. Then, connect the steel pipes on both sides of the operating platform to the wire loops outside the reinforcing cage through the lower hooks. Install the over-grouting detection instrument for cast-in-place piles on both sides of the steel pipes below the operating platform, close to the wall layer of the cast-in-place pile, so that both sets of steel pipes are equipped with the over-grouting detection instrument. Then, determine the elevation of the top of the cast-in-place pile as the baseline according to the over-grouting requirements at the sensing endpoint of the over-grouting detection instrument.
[0010] S3. Set up a fuse structure: Place a fuse controller on the surface of the pad plate on one side of the pad block. After the input terminal of the fuse controller is connected to the power supply, connect the wire to its own input terminal. The wire is wrapped around the steel pipe above the over-grouting detector of the cast-in-place pile.
[0011] S4. Setting up filling facilities: Using the boom of external machinery, the funnel is hoisted to the operating platform by a hoisting rope. A sinking pipe is installed below the funnel and extends downward into the hole of the bored pile. Then the concrete pump truck's concrete pump extends to the top of the funnel opening.
[0012] S5. Concrete Pouring: After the over-pouring detector for cast-in-place piles sets the baseline, the concrete pump pours concrete from the funnel into the bored cast-in-place pile to embed the reinforcing cage. If only one sensing endpoint connected to the over-pouring detector detects and displays that the concrete has reached the predetermined height during the casting process, it is necessary to vibrate the driven pipe to level the concrete at the top of the pile before pouring an appropriate amount to the elevation baseline position set by the two sets of over-pouring detectors, and then turn off the concrete pump.
[0013] S6. Fusion-shield separation: When both sets of over-grouting detectors for cast-in-place piles show that the design over-grouting height has been reached, the fuse controller immediately opens to obtain the power supply current. The current is transmitted through the fuse controller and wires in the steel pipeline to the lower hook to heat the wire collar. After heating, the fusible gasket between the wire collar and the longitudinal reinforcement of the steel cage melts, causing the wire collar to separate from the longitudinal reinforcement of the steel cage. At the same time, the spring inside the upper hook will automatically bounce upward with the wire collar after losing the load of the steel cage at the lower hook. Due to the restraint of the elastic rubber rope, it can be ensured that after the cast-in-place pile reaches the design elevation, the entire steel pipeline is always connected to the operating platform.
[0014] S7. Dismantling Equipment: After the lower hook with the wire collar is detached from the rebar cage, disconnect the fuse controller and remove it from above the operating platform. Untie the elastic rubber rope and remove the steel pipeline with the upper and lower hooks and the over-pouring detector of the cast-in-place pile from the operating platform for the baseline positioning of the next cast-in-place pile. Then, the boom is lifted off the operating platform with the funnel and sinker pipe by the hoisting rope under the drive of the hoisting machinery. The concrete pump truck is retrieved and the concrete boom is driven away. The operating platform is removed from the pad block with the spring. Then the pad block and the pad plate are removed from the site soil.
[0015] Furthermore, the over-pouring detector for cast-in-place piles uses the commonly used SL0CG30 concrete top over-pouring monitor in China. The sensor of this device can reach 18m in length, the sensor operating temperature is 0~50℃, and the power supply is 12V / 5A. It can be used simultaneously for two or more over-pouring detectors for cast-in-place piles. When the sensing end point comes into contact with the poured concrete, the corresponding indicator light of the over-pouring detector for cast-in-place piles will automatically light up.
[0016] Furthermore, the fuse controller is a model 170M1567 fuse. This fuse can actively open the power supply-connected fuse controller after the concrete is poured to the elevation of the cast-in-place pile according to the detection signal indication of the over-pouring detector of the cast-in-place pile, so that the current is transmitted to the steel wire collar connected to the lower hook through the wire and steel pipe.
[0017] Furthermore, the wire sling is equipped with an electromagnetic heating coil inside. When the wire sling is energized, electromagnetic heat will be generated in the middle. The outside of the wire sling is a wire rope that can withstand a certain strength. The fusible gasket between the wire sling and the longitudinal reinforcement of the steel cage is a customized fusible gasket made of PE / EVA material, and its thickness can be set according to construction needs.
[0018] Furthermore, the outer part of the steel pipeline is made of steel pipe, and the diameter of the steel pipe is determined according to the diameter of the internal steel wire rope. The internal steel wire rope is made of galvanized stainless steel. The steel wire rope product uses 304, 304L, 316 or 316L stainless acid-resistant steel as raw material. The produced steel wire rope uses multiple strands, and the specific diameter of the steel wire rope needs to be determined according to the diameter of the cast-in-place pile and the quality of the selected reinforcing cage.
[0019] Furthermore, the lower and middle hook locks must be fixed to the wire sling to ensure that after the fuse controller is opened, the current passes through the steel pipe and the steel pipe hook to heat and melt the fusible gasket, allowing it to automatically detach. The upper hook must be stably connected to the operating platform and secured a second time with an elastic rubber rope to prevent the steel pipe from detaching due to the rebound after the lower hook suddenly separates.
[0020] Furthermore, a spring is provided between the upper hook of the steel pipeline and the operating platform. The upper inner diameter of the spring is fixed to the upper hook, and the lower part of the spring is fixed to the corresponding groove position on the operating platform. The spring type is a composite steel wire rubber spring, and its material is natural rubber and steel wire coil spring. The shape of the spring is a spiral cylinder.
[0021] In summary, the present invention includes at least one of the following technical benefits:
[0022] 1. This invention, through the use of a cast-in-place pile over-pouring detector in conjunction with a steel pipeline, can automatically detach the steel wire collar after the pile has been poured to the reference elevation, thereby automatically controlling the elevation of the cast-in-place pile, reducing the over-pouring height of the bored cast-in-place pile, avoiding a large number of over-pouring phenomena, and saving the consumption of concrete materials.
[0023] 2. By controlling the precise pouring height, this invention avoids the difficulty of subsequent pile head removal, shortens construction time, saves manpower to a certain extent, shortens the pile foundation construction period, and saves construction costs.
[0024] 3. After the initial ground leveling and positioning, the present invention uses two over-pouring pile detectors to accurately locate the pile head elevation on the ground simultaneously, effectively solving the problem of inaccurate pile head positioning during construction. Attached Figure Description
[0025] Figure 1 This is an overall plan view of the present invention;
[0026] Figure 2 For the present invention Figure 1 Enlarged view of part A in the diagram;
[0027] Figure 3 For the present invention Figure 1 Enlarged view of part B in the diagram;
[0028] Figure 4 This is a schematic diagram of the steel pipeline of the present invention.
[0029] In the diagram: 1. Lifting rod; 2. Lifting rope; 3. Concrete pump; 4. Funnel; 5. Sinking pipe; 6. Wire; 7. Power supply; 8. Fuse controller; 9. Operating platform; 10. Pad plate; 11. Over-pouring detector for cast-in-place piles; 11-1. Sensing endpoint; 12. Pad block; 13. Site soil; 14. Reinforcing cage; 14-1. Longitudinal reinforcement of the reinforcing cage; 15. Concrete; 16. Baseline; 17. Steel pipe; 17-1. Spring; 17-2. Upper hook; 17-3. Lower hook; 17-4. Elastic rubber rope; 18. Steel wire sling; 19. Fusible gasket. Detailed Implementation
[0030] To make the technical means, creative features, objectives and effects of this invention easier to understand, the invention will be further described below in conjunction with specific embodiments.
[0031] like Figure 1-4 As shown, a construction process for precise elevation positioning of cast-in-place concrete piles includes the following steps:
[0032] S1. Setting up a platform: First, on the leveled soil 13, after determining the specific location of the cast-in-place pile according to the design requirements, a steel cage 14 with longitudinal steel bars 14-1 is embedded in the hole of the soil 13 according to the hole-forming process of the bored cast-in-place pile. A pad plate 10 is laid around the design location of the bored cast-in-place pile on the soil 13 of the bored cast-in-place pile, and a pad block 12 is set on top of the pad plate 10. An operating platform 9 is set on top of the pad block 12.
[0033] S2. Install the over-grouting detector 11 for cast-in-place piles: Install two sets of springs 17-1 symmetrically on the operating platform 9. Use elastic rubber ropes 17-4 to fix the upper hooks 17-2 of the steel pipes 17 at the springs 17-1 of the operating platform 9 to complete the installation of the two sets of steel pipes 17. Use fusible gaskets 19 to fix the wire loops 18 at the longitudinal reinforcement 14-1 of the reinforcing cage 14. Then, connect the steel pipes 17 symmetrically on both sides of the operating platform 9 to the wire loops 18 outside the reinforcing cage 14 through the lower hooks 17-3. Install the over-grouting detector 11 for cast-in-place piles on both sides of the steel pipes 17 below the operating platform 9 near the wall layer of the cast-in-place pile, so that both sets of steel pipes 17 are equipped with the over-grouting detector 11. Then, the sensing end point 11-1 at the end of the over-grouting detector 11 determines the elevation of the top of the cast-in-place pile as the baseline 16 according to the over-grouting requirements.
[0034] S3. Set up a fuse structure: Place a fuse controller 8 on the surface of the pad plate 10 on one side of the pad block 12. After the input terminal of the fuse controller 8 is connected to the power supply 7, connect the wire 6 to its own input terminal. The wire of the wire 6 is wrapped around the steel pipe 17 above the over-grouting detector 11 of the cast-in-place pile.
[0035] S4. Setting up filling facilities: Using the boom 1 of external machinery, the funnel 4 is hoisted to the operating platform 9 via the hoisting rope 2. The funnel 4 is connected to the bottom of the sinker 5, which extends downward into the hole of the bored pile. Then the concrete pump 3 of the concrete pump truck extends to the top of the funnel 4.
[0036] S5. Concrete Pouring: After the over-pouring detector 11 sets the baseline 16, the concrete pump 3 pours concrete 15 into the bored pile from the funnel 4 to embed the reinforcing cage 14. If only one sensing end point 11-1 connected to the over-pouring detector 11 detects and displays that the concrete 15 has reached the predetermined height during the pile pouring process, it is necessary to vibrate the driven pipe 5 to level the concrete 15 at the top of the pile before pouring an appropriate amount to the elevation baseline 16 set by the two sets of over-pouring detectors 11. Then, the concrete pump 3 is turned off.
[0037] S6. Fusion-shield separation: When both sets of over-grouting detectors 11 show that the design over-grouting height has been reached, the fuse controller 8 immediately turns on to obtain the current from the power supply 7. The current is transmitted through the fuse controller 8, the wire 6, and the steel pipe 17 to the lower hook 17-3 to heat the wire collar 18. After heating, the fusible gasket 19 between the wire collar 18 and the longitudinal reinforcement 14-1 of the steel cage melts, causing the wire collar 18 to separate from the longitudinal reinforcement 14-1 of the steel cage. At the same time, the spring 17-1 inside the upper hook 17-2 will automatically bounce upward with the wire collar 18 after losing the load of the steel cage 14 at the lower hook 17-3. Due to the restraint of the elastic rubber rope 17-4, it can be ensured that after the cast-in-place pile reaches the design elevation, the entire steel pipe 17 is always connected to the operating platform 9.
[0038] S7. Dismantling Equipment: After the lower hook 17-3, with the wire collar 18, is detached from the reinforcing cage 14, the fuse controller 8 is disconnected and removed from above the operating platform 9. The elastic rubber rope 17-4 is untied, and the steel pipe 17 with the upper hook 17-2 and the lower hook 17-3 and the over-pouring detector 11 for the cast-in-place pile are removed from the operating platform 9 for positioning the baseline 16 of the next cast-in-place pile. Then, the boom 1 is lifted off the operating platform 9 by the hoisting rope 2 with the funnel 4 and the sinking pipe 5 under the drive of the hoisting machinery. The concrete pump truck is retracted and the concrete boom 3 is driven away. The operating platform 9, with the spring 17-1, is removed from the pad block 12. Then, the pad block 12 and the pad plate 10 are removed from the site soil 13.
[0039] Among them, the over-pouring detector 11 for cast-in-place piles adopts the SL0CG30 concrete top over-pouring monitoring instrument commonly used in China. The sensor length of this device can reach 18m, the sensor working temperature is 0~50℃, and the power supply of the device is 12V / 5A. Two or even more over-pouring detectors 11 for cast-in-place piles can be used at the same time. When the sensing end point 11-1 contacts the poured concrete 15, the corresponding indicator light of the over-pouring detector 11 for cast-in-place piles will automatically light up.
[0040] Among them, the fuse controller 8 is a fuse of model 170M1567. The fuse can actively turn on the fuse controller 8 connected to the power supply 7 after the concrete 15 is poured to the elevation of the cast-in-place pile according to the detection signal indication of the over-pouring detector 11. This allows the current to be transmitted through the conductor 6 and the steel pipe 17 to the steel wire collar 18 connected to the lower hook 17-3.
[0041] The wire sling 18 is equipped with an electromagnetic heating coil inside. When the wire sling 18 is energized, electromagnetic heat will be generated in the middle. The outside of the wire sling 18 is a wire rope that can withstand a certain strength. The fusible gasket 19 between the wire sling 18 and the longitudinal reinforcement 14-1 of the steel cage is a customized fusible gasket 19 made of PE / EVA material, and its thickness can be set according to construction needs.
[0042] The steel pipe 17 has an outer steel pipe body, the diameter of which is determined by the diameter of the internal wire rope. The internal wire rope is made of galvanized stainless steel, using 304, 304L, 316, or 316L stainless acid-resistant steel as raw material. The produced wire rope is multi-stranded, and the specific diameter needs to be determined based on the diameter of the cast-in-place pile and the weight of the selected reinforcing cage 14. For example, the wire rope may use a multi-strand (7*7) structure with single-strand diameters of 0.5, 0.8, 1.0, 1.2, 1.5, 1.8, 2.0, 3.0, and 4.0 mm. The thicknesses are 5.0, 6.0, and 8.0 mm, with corresponding mass per 100m of 0.08, 0.26, 0.40, 0.65, 0.93, 1.35, 1.57, 3.70, 6.50, 10.50, 15.10, and 26.60 kg, respectively. The corresponding maximum load-bearing capacities are 14.40, 47.00, 65.00, 122.40, 170.40, 229.60, 229.60, 650.00, 970.40, 1500.00, 1898.00, and 4142.00 kg, respectively.
[0043] Among them, the locking device of the lower hook 17-3 must be fixed to the wire collar 18 to ensure that after the fuse controller 8 is opened, the current passes through the steel pipe 17 and the steel pipe hook to heat and melt the fusible gasket 19 and can automatically detach. The upper hook 17-2 must be stably connected to the operating platform 9 and be fixed again by the elastic rubber rope 17-4 to avoid the rebound after the lower hook 17-3 suddenly separates and causes the steel pipe 17 to detach.
[0044] A spring 17-1 is installed between the upper hook 17-2 of the steel pipe 17 and the operating platform 9. The upper inner diameter of the spring 17-1 is fixed to the upper hook 17-2, and the lower part of the spring 17-1 is fixed to the corresponding groove position on the operating platform 9. The spring 17-1 is a composite steel wire rubber spring, and its material is natural rubber and steel wire coil spring. The shape of the spring 17-1 is a spiral cylinder. Its model is 150mm (outer diameter) * 265mm (free height) * 80mm (inner diameter). Its working deformation is 3mm, its stiffness is 180~600kg / cm, and its static load is 500~1800kg.
[0045] It should be noted that this invention is a construction process for precise positioning of concrete cast-in-place pile elevation. All components in this invention are known to those skilled in the art, and their structures and principles can be learned by those skilled in the art through technical manuals or conventional experimental methods.
[0046] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the present invention as claimed. The scope of protection of this invention is defined by the appended claims and their equivalents.
Claims
1. A construction process for precise elevation positioning of cast-in-place concrete piles, characterized in that: Includes the following steps: S1. Setting up a platform: First, on the leveled soil (13), after determining the specific location of the cast-in-place pile according to the design requirements, a steel cage (14) with longitudinal steel bars (14-1) is buried in the hole of the soil (13) according to the hole-forming process of the bored cast-in-place pile. A pad plate (10) is laid on the soil (13) of the bored cast-in-place pile according to the design location of the bored cast-in-place pile, and a pad block (12) is set on top of the pad plate (10). An operating platform (9) is set on top of the pad block (12). S2. Install the over-grouting detector for cast-in-place piles (11): Install two sets of springs (17-1) symmetrically on the operating platform (9). Use elastic rubber ropes (17-4) to fix the upper hooks (17-2) of the steel pipes (17) at the springs (17-1) of the operating platform (9) to complete the installation of the two sets of steel pipes (17). Use fusible gaskets (19) to fix the wire collars (18) at the longitudinal reinforcement (14-1) of the steel cage (14). Then, use symmetrical steel pipes (17-2) on both sides of the operating platform (9) to install the steel pipes (17-1). 7) The lower hook (17-3) is connected to the wire loop (18) outside the steel cage (14). On both sides of the steel pipeline (17) below the operating platform (9) near the wall layer of the cast-in-place pile, the cast-in-place pile over-grouting detector (11) is installed respectively, so that the cast-in-place pile over-grouting detector (11) is installed at both sets of steel pipelines (17). Then, the sensing end point (11-1) at the end of the cast-in-place pile over-grouting detector (11) determines the elevation of the top of the cast-in-place pile as the baseline (16) according to the over-grouting requirements. S3. Set up a fuse structure: Place a fuse controller (8) on the surface of the pad (10) on one side of the pad block (12). After the input end of the fuse controller (8) is connected to the power supply (7), connect the wire (6) with its own input end. The wire (6) is wrapped around the steel pipe (17) above the over-irrigation detector (11) of the grouting pile. S4. Setting up filling facilities: Using the boom (1) of external machinery, the funnel (4) is hoisted to the operating platform (9) via the hoisting rope (2). A sinking pipe (5) is installed below the funnel (4) and extends downward into the hole of the bored pile. Then the concrete pump (3) of the concrete pump truck extends to the top of the funnel (4). S5. Concrete pouring: After the over-pouring detector (11) of the cast-in-place pile is set to the baseline (16), the concrete pump (3) pours concrete (15) into the bored cast-in-place pile from the funnel (4) to embed the steel cage (14). If only one sensing endpoint (11-1) connected to the over-pouring detector (11) of the cast-in-place pile detects and displays that the concrete (15) has reached the predetermined height during the casting process, it is necessary to vibrate the driven pipe (5) to level the concrete (15) at the top of the pile before pouring an appropriate amount to the elevation baseline (16) set by the two sets of over-pouring detectors (11). Then, the concrete pump (3) is turned off. S6, Fusion separation: When both sets of over-grouting detectors (11) show that the design over-grouting height has been reached, the fuse controller (8) immediately turns on to obtain the current from the power supply (7). The current is transmitted through the fuse controller (8) and the wire (6) in the steel pipeline (17) to the lower hook (17-3) to heat the wire collar (18). After heating, the fusible gasket (19) between the wire collar (18) and the longitudinal reinforcement (14-1) of the steel cage melts, causing the wire collar (18) to separate from the longitudinal reinforcement (14-1) of the steel cage. At the same time, the spring (17-1) inside the upper hook (17-2) will automatically lift the wire collar (18) upward after losing the load of the steel cage (14) at the lower hook (17-3). Due to the constraint of the elastic rubber rope (17-4), it can be ensured that after the cast-in-place pile reaches the design elevation, the entire steel pipeline (17) is always connected to the operating platform (9). S7. Dismantling facilities: After the lower hook (17-3) with the wire collar (18) is removed from the steel cage (14), disconnect the fuse controller (8) and remove it from above the operating platform (9). Untie the elastic rubber rope (17-4) and remove the steel pipe (17) with the upper hook (17-2) and the lower hook (17-3) and the over-pouring detector (11) of the cast-in-place pile from the operating platform (9) for positioning the baseline (16) of the next cast-in-place pile. Then, the boom (1) is lifted off the operating platform (9) with the hoisting rope (2) and the funnel (4) and the sinker (5) under the drive of the hoisting machinery. The concrete pump truck retracts the concrete pump (3) and drives away. The operating platform (9) with the spring (17-1) removes the pad (12) and then removes the pad (12) and the pad plate (10) from the site soil (13).
2. The construction process for precise positioning of the grade of a cast-in-place concrete pile according to claim 1, characterized in that: The cast-in-place pile over-pouring detector (11) is the commonly used SL0CG30 concrete top over-pouring monitor in China. The sensor length of this device can reach 18m, the sensor working temperature is 0~50℃, and the power supply is 12V / 5A. It can be used simultaneously for two or more cast-in-place pile over-pouring detectors (11). When the sensing end point (11-1) comes into contact with the poured concrete (15), the corresponding indicator light of the cast-in-place pile over-pouring detector (11) will automatically light up.
3. The construction process for precise positioning of the grade of a cast-in-place concrete pile according to claim 1, characterized in that: The fuse controller (8) is a model 170M1567 fuse. The fuse can actively turn on the fuse controller (8) connected to the power supply (7) after the concrete (15) is poured to the elevation of the cast-in-place pile according to the detection signal indication of the over-pouring detector (11). This allows the current to be transmitted through the wire (6) and the steel pipe (17) to the steel wire collar (18) connected to the lower hook (17-3).
4. The construction process for precise positioning of the grade of a cast-in-place concrete pile according to claim 1, characterized in that: The wire sling (18) is equipped with an electromagnetic heating coil inside. When the wire sling (18) is energized, electromagnetic heat will be generated in the middle. The outside of the wire sling (18) is a wire rope that can withstand a certain strength. The fusible gasket (19) between the wire sling (18) and the longitudinal reinforcement (14-1) of the steel cage is a customized fusible gasket (19) made of PE / EVA material. Its thickness can be set according to construction needs.
5. The construction process for precise positioning of the grade of a cast-in-place concrete pile according to claim 1, characterized in that: The steel pipe (17) is made of steel pipe material on the outside. The diameter of the steel pipe is determined according to the diameter of the internal steel wire rope. The steel wire rope inside the steel pipe is made of galvanized stainless steel. The steel wire rope product uses 304 or 304L or 316 or 316L stainless acid-resistant steel as raw material. The steel wire rope produced is multi-stranded. The specific diameter of the steel wire rope needs to be determined according to the diameter of the cast-in-place pile and the quality of the selected steel cage (14).
6. The construction process for precise positioning of the grade of a cast-in-place concrete pile according to claim 1, characterized in that: The lower hook (17-3) lock must be fixed to the wire collar (18) to ensure that after the fuse controller (8) is opened, the current will heat and melt the fusible gasket (19) through the steel pipe (17) and the steel pipe hook, and then automatically detach. The upper hook (17-2) must be stably connected to the operating platform (9) and be fixed again by the elastic rubber rope (17-4) to avoid the steel pipe (17) from detaching due to the rebound after the lower hook (17-3) suddenly separates.
7. The construction process for precise positioning of the grade of a cast-in-place concrete pile according to claim 1, characterized in that: A spring (17-1) is provided between the upper hook (17-2) of the steel pipeline (17) and the operating platform (9). The upper inner diameter of the spring (17-1) is fixed to the upper hook (17-2), and the lower part of the spring (17-1) is fixed to the corresponding groove position on the operating platform (9). The spring (17-1) is a composite steel wire rubber spring (17-1), and its material is natural rubber and steel wire coil spring. The shape of the spring (17-1) is a spiral cylinder.