Mounting structure of reinforcement cage in cast-in-situ bored pile

Abstract

The utility model relates to a mounting structure of a reinforcement cage in a cast-in-situ bored pile, and relates to the technical field of civil construction. The mounting structure of the reinforcement cage in the cast-in-situ bored pile comprises a plurality of hanging bars, and the hanging bars are distributed in the circumferential direction of the reinforcement cage at intervals; the hanging bar is located at the upper end of the reinforcement cage, and the length direction of the hanging bar is consistent with that of the reinforcement cage. One end of the hanging bar is welded on the reinforcement cage main bar, the other end of the hanging bar is provided with a hanging ring, and the hanging ring of the hanging bar is welded and fixedly connected with the pile casing at the hole opening of the drill hole. According to the cast-in-situ bored pile, the hanging bars are arranged on the reinforcement cage, the hanging bars are fixedly connected with the pile casing in a welded mode, the stability of the whole structure is enhanced, displacement of the reinforcement cage caused by upward buoyancy force generated by concrete pouring is effectively prevented, the anti-floating capacity of the reinforcement cage is remarkably improved, and therefore the construction quality of the cast-in-situ bored pile is ensured.

Description

Technical Field

[0001] The present application relates to the technical field of civil construction, and in particular to an installation structure of a steel cage in a bored cast-in-place pile. Background Art

[0002] With the continuous acceleration of urbanization, there are more and more high-rise buildings in cities, and the application of pile foundations is becoming more and more extensive. In the construction of pile foundations, bored cast-in-place piles are the most common. Bored cast-in-place piles are suitable for various foundation soils. The current common construction method is: first use a drilling machine to drill the pile hole, then hang a steel cage in the hole, and finally pour concrete into the hole to form a reinforced concrete pile. The concrete in the bored cast-in-place pile has high compressive strength but very low tensile strength. The steel cage in the bored cast-in-place pile mainly plays a tensile role and constrains the concrete of the pile body so that it can withstand a certain axial tension. Whether the steel cage is fixed in place will directly affect the quality of the entire bored cast-in-place pile and the quality of the entire building.

[0003] Due to the rapid development of mechanization and equipment, a variety of small-scale hole-forming machines have appeared on the market. Therefore, small-diameter bored piles have the natural advantage of not being restricted by the site during construction, and their application is becoming more and more extensive. In the process of pouring concrete, when the concrete is poured to the bottom of the steel cage, the poured concrete flips out of the guide tube, and the pressure from the bottom to the top is relatively large, which can easily lift the steel cage up. The steel cage in the small-diameter bored pile is smaller and lighter, so it is easier for the steel cage to float when pouring concrete, which is more likely to cause pile foundation construction quality accidents.

[0004] In order to ensure the construction quality of bored piles, it is necessary to prevent the steel cage from floating and shifting. In the related art, in order to smoothly place the grouting conduit and carry out the grouting normally, a bending part and an anti-floating grid are set at the bottom of the steel cage to achieve the anti-floating of the steel cage. However, this structural setting will affect the smooth lowering of the steel cage, and at the same time, its anti-floating effect is not good. Utility Model Content

[0005] In order to improve the anti-floating effect of the steel cage in bored cast-in-place pile construction and ensure the smooth placement of the steel cage, the present application provides an installation structure of the steel cage in bored cast-in-place piles.

[0006] The installation structure of the steel cage in the bored pile provided in this application adopts the following technical solution:

[0007] A mounting structure for a steel cage in a bored pile comprises a plurality of hangers, all of which are spaced apart along the circumference of the steel cage; the hangers are located at the upper end of the steel cage and the length direction of the hangers is consistent with the length direction of the steel cage; one end of the hanger is welded to the main steel cage bar, the other end of the hanger is provided with a hanging ring, and the hanging ring of the hanger is welded and fixedly connected to a casing at a borehole opening.

[0008] By adopting the above technical solution, the provided hanging bars can be used to assist the lifting equipment to lift the steel cage with a hook, thereby facilitating the placement of the steel cage; in this application, the structural strength of the hanging bars is enhanced, and the connection method thereof is optimized, thereby ensuring the stability and reliability of the connection between the hanging bars and the steel cage. After the steel cage is placed in place, the hanging bars are welded and fixed to the casing, thereby enhancing the stability of the entire structure. This design is not only easy to operate in construction, but also can effectively prevent the displacement of the steel cage caused by the buoyancy generated by the pouring of concrete, significantly improving the anti-floating ability of the steel cage, thereby ensuring the construction quality of bored piles.

[0009] Optionally, each hanger rod is composed of two three-level ribbed steel bars placed side by side and fixedly connected by welding.

[0010] By adopting the above technical solution, the structural strength and rigidity of the hanger bar are enhanced.

[0011] Optionally, the lap length L between the hanger bar and the main reinforcement of the steel cage is 20d.

[0012] By adopting the above technical solution, the stability of the connection between the hanger rod and the steel cage is improved.

[0013] Optionally, the number of the hanger bars is three and they are arranged at equal intervals along the circumference of the steel cage.

[0014] By adopting the above technical solution, the buoyancy force on the steel cage can be evenly and reliably transmitted to the casing through multiple hangers, ensuring the uniform stability of the force on the steel cage, ensuring the stability of the connection between the steel cage and the casing, and effectively preventing the steel cage from tilting.

[0015] Optionally, the hanger has one end of a hanger ring extending in a direction away from the steel cage; and an insertion rod is inserted into the hanger ring.

[0016] By adopting the above technical solution, the fixing effect of the steel cage is further enhanced. At the same time, the rods inserted into the lifting rings and overlapped on the ground can also prevent the steel cage from falling, thereby improving the accuracy of the placement of the steel cage.

[0017] Optionally, the installation structure further includes a sleeper arranged at the opening of the drill hole, the insertion rod is arranged along the radial direction of the steel cage and the two ends of the insertion rod are respectively located on the sleepers on both sides of the drill hole.

[0018] By adopting the above technical solution, the insertion rod can be fixedly connected to the sleeper, and heavy objects can be placed on the sleeper, or the counterweight block can be directly pressed on the insertion rod to maintain the stability of the insertion rod; the sleeper has a large contact area with the ground and can provide stable support, thereby ensuring the stability of the steel cage.

[0019] Optionally, the mounting structure further includes a fixed shaft and a roller, wherein the roller is rotatably arranged on the fixed shaft, the fixed shaft is fixedly connected to the steel cage, the axial direction of the roller is perpendicular to the central axis of the steel cage, and the roller can roll on the wall of the borehole when the steel cage is moved downward in the borehole.

[0020] By adopting the above technical solution, when the steel cage is moved down in the drill hole, the roller can roll close to the wall of the drill hole, thereby reducing the friction resistance and making the placement of the steel cage smoother. At the same time, the roller can control the distance between the steel cage and the wall of the drill hole, prevent the steel cage from tilting, and maintain the stability of the steel cage.

[0021] Optionally, a plurality of barbed teeth are arranged on the outer circumferential surface of the roller, and the plurality of barbed teeth are arranged at intervals along the circumference of the roller. When the barbed teeth on the roller rotate with the roller to contact the wall of the drill hole, the tips of the barbed teeth are tilted upward.

[0022] By adopting the above technical solution, the barbed teeth on these rollers will not limit the steel cage through the rolling of the rollers when the steel cage moves downward. When the steel cage moves upward due to the buoyancy of concrete, the barbed teeth on these rollers will be embedded in the soil layer of the drilled hole wall to form a pull-out anchor, thereby providing pull-out resistance to the steel cage and effectively preventing the steel cage from floating up.

[0023] Optionally, the roller is made of concrete, the fixed shaft is made of steel bars, the middle portion of the fixed shaft is inserted into a through hole in the middle portion of the roller, and both ends of the fixed shaft are respectively welded to two adjacent main bars of the steel cage.

[0024] By adopting the above technical solution, the strength and rigidity of the structure are guaranteed while taking into account the economy and ease of processing.

[0025] In summary, the present application includes at least one of the following beneficial technical effects:

[0026] 1. The structure in the present application can overcome the problem of the floating of the steel cage during concrete pouring in bored pile construction, which affects the quality of the pile body, thereby making small-diameter dry-hole bored piles have a broader prospect and applicability, can meet on-site construction requirements, and generate huge economic benefits.

[0027] 2. In this application, by enhancing the structural strength of the hanger bar and optimizing its connection method, the stability and reliability of the connection between the hanger bar and the steel cage are guaranteed, the anti-floating ability of the steel cage is significantly enhanced, and the construction quality of the bored piles is ensured.

[0028] 3. The roller with barbed teeth is provided in the present application, which provides additional pull-out resistance for the steel cage and further prevents the steel cage from floating up. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 It is a schematic diagram of the installation structure of the steel cage in this application.

[0030] Figure 2 yes Figure 1 Cross-sectional view at AA in the middle.

[0031] Figure 3 yes Figure 1 Cross-sectional view at BB in the middle.

[0032] Figure 4 It is a schematic diagram of the roller-related structure in this application.

[0033] In the figure:

[0034] 10. Suspension rod; 11. Suspension ring;

[0035] 20. Steel cage; 21. Main reinforcement of steel cage; 22. Ring reinforcement of steel cage; 23. Spiral reinforcement of steel cage;

[0036] 30. Insert the rod;

[0037] 40. Sleepers;

[0038] 50. Casing;

[0039] 60. Fixed axis;

[0040] 70. Roller; 71. Barbed hobbing. DETAILED DESCRIPTION

[0041] The following is combined with Figure 1 -Attached Figure 4 , further details of this application are given.

[0042] In the construction of bored cast-in-place piles, the pile hole is first drilled with a drilling machine, then a steel cage is hung in the hole, and finally concrete is poured into the hole to form a reinforced concrete pile.

[0043] Reference Figure 1 and Figure 2As shown, before drilling, it is necessary to bury the casing 50 to locate the pile position to be drilled. The casing 50 is usually a steel casing with a wall thickness of 10mm. When positioning the casing 50, first take the center of the pile position as the center of the circle, and determine the position of the casing 50 on the soil according to the radius of the casing 50. After the casing 50 is in place, apply pressure to bury the casing 50 about 50cm. If it is difficult to press down, you can first dig out a part of the soil at the hole position, and then place the casing 50 underground. During the burial process, check whether the casing 50 is vertical. If deflection is found, it should be corrected in time. After the onshore casing 50 is buried in place, the outer side of the casing 50 is backfilled and compacted with clay to prevent water leakage around the casing 50. The backfill thickness is about 40-45cm, and the top height of the casing 50 is 0.4-0.6m above the ground. The deviation of the casing position from the hole center shall not be greater than 50mm. The casing 50 not only plays the role of positioning and preventing the hole wall from collapsing, but also has the functions of isolating surface water, protecting the ground at the hole mouth, fixing the pile hole position and guiding the drill bit.

[0044] The steel cage 20 can be assembled on site or assembled in other areas and then transported to the construction site. Figure 1 , Figure 2 and Figure 3 As shown, the steel cage 20 generally includes a plurality of steel cage main bars 21, a plurality of steel cage annular reinforcement bars 22 and a plurality of steel cage spiral bars 23. All the steel cage main bars 21 are arranged in the same direction and distributed on the circumference of the same circle. The steel cage annular reinforcement bars 22 are arranged on the inner side of all the main bars and are welded and fixedly connected to all the steel cage main bars 21 at the same time. The steel cage spiral bars 23 are spirally wrapped around the outer side of all the steel cage main bars 21 and are welded and fixedly connected to each steel cage main bar 21.

[0045] Reference Figure 1 , Figure 2 and Figure 3 As shown, the installation structure in the present application includes a plurality of hangers 10, all of which are spaced apart along the circumference of the steel cage 20; the hangers 10 are located at the upper end of the steel cage 20 and the length direction of the hangers 10 is consistent with the length direction of the steel cage 20; one end of the hanger 10 is welded to the main reinforcement 21 of the steel cage, and the other end of the hanger 10 has a lifting ring 11, and the lifting ring 11 of the hanger 10 is welded and fixedly connected to the casing 50 at the borehole mouth, so that the entire steel cage 20 and the casing 50 are fixedly connected together by the hanger 10 to form an integral stable structure, which effectively prevents the steel cage 20 from floating up.

[0046] In the present application, each hanger bar 10 is composed of two three-level ribbed steel bars that are placed side by side and welded together; the lap length L between the end of the hanger bar 10 and the main reinforcement 21 of the reinforcement cage is 20d, which is used to improve the stability of the connection between the hanger bar 10 and the reinforcement cage 20. The diameter of the hanger bar 10 is consistent with the diameter of the main reinforcement 21 of the reinforcement cage, and the number of the hanger bars 10 can be three and they are arranged at equal intervals along the circumference of the reinforcement cage 20.

[0047] Reference Figure 1 As shown, in the present application, the hanger 10 has an end of a lifting ring 11 extending in a direction away from the steel cage 20; a plug rod 30 is inserted into the lifting ring 11, and a sleeper 40 is also provided at the opening of the drill hole, the plug rod 30 is arranged along the radial direction of the steel cage 20 and the two ends of the plug rod 30 are respectively located on the sleepers 40 on both sides of the drill hole; the sleepers 40 have a large contact area with the ground and can provide stable support, the plug rod 30 can be fixedly connected to the sleepers 40, and a heavy object can be arranged on the sleepers 40, or a counterweight block can be directly used to press on the plug rod 30 to keep the plug rod 30 stable; in this way, the steel cage 20 is limited by the plug rod 30, which can prevent the steel cage 20 from falling and also prevent the steel cage 20 from floating.

[0048] Further, see Figure 1 and Figure 4 As shown, the installation structure in the present application also includes a fixed shaft 60 and a roller 70, the roller 70 is rotatably arranged on the fixed shaft 60, the fixed shaft 60 is fixedly connected to the steel cage 20, the axial direction of the roller 70 is perpendicular to the central axis of the steel cage 20, and the roller 70 can roll on the wall of the borehole when the steel cage 20 is moved down and placed in the borehole; when the steel cage 20 is moved down and placed in the borehole, the roller 70 can roll close to the wall of the borehole, thereby reducing friction resistance and making the placement of the steel cage 20 smoother. At the same time, the roller 70 can control the distance between the steel cage 20 and the wall of the borehole, prevent the steel cage 20 from tilting, and maintain the stability of the steel cage 20. A plurality of barbed teeth 71 are arranged on the outer circumferential surface of the roller 70, and the plurality of barbed teeth 71 are arranged at intervals along the circumference of the roller 70. When the barbed teeth 71 on the roller 70 rotate with the roller 70 to contact the wall of the borehole, the tips of the barbed teeth 71 are tilted upward; when the steel cage 20 moves downward, the barbed teeth 71 on the roller 70 will not limit the steel cage 20 through the rolling of the roller 70. When the steel cage 20 moves upward due to the buoyancy of the concrete, the barbed teeth 71 on the roller 70 will be embedded in the soil layer of the borehole wall to form a pull-out anchor, thereby providing pull-out resistance to the steel cage 20 and effectively preventing the steel cage 20 from floating up.

[0049] The roller 70 in the present application is made of concrete, and the fixed shaft 60 is made of steel bars. The middle part of the fixed shaft 60 is inserted into the through hole in the middle part of the roller 70, and the two ends of the fixed shaft 60 are respectively welded to two adjacent main bars 21 of the steel cage; this ensures the strength and rigidity of the structure while taking into account economy and ease of processing.

[0050] The implementation principle of this embodiment is: through the specially designed hanging rod 10, including its material selection, quantity configuration and connection mode with the steel cage 20 and the casing 50, the steel cage 20 is fixed, and the anti-floating ability of the steel cage 20 is significantly improved. In this application, a roller 70 with barbed hobbing teeth 71 is further provided, which provides guidance for the placement of the steel cage 20, can also prevent the steel cage 20 from tilting, and provides additional reverse pull-out resistance for the steel cage 20, further preventing the steel cage 20 from floating; thereby ensuring the overall construction quality of the bored pile and improving the safety and stability of the building.

[0051] The embodiments of this specific implementation are all preferred embodiments of the present application, and are not intended to limit the protection scope of the present application. The same components are represented by the same figure marks. Therefore, any equivalent changes made based on the structure, shape, and principle of the present application should be included in the protection scope of the present application.

Claims

1. A mounting structure for a steel cage in a bored pile, comprising a plurality of hanger bars (10), all of which are spaced apart and distributed along the circumference of the steel cage (20); characterized in that: The hanger bar (10) is located at the upper end of the steel cage (20) and the length direction of the hanger bar (10) is consistent with the length direction of the steel cage (20); one end of the hanger bar (10) is welded to the main steel cage bar (21), and the other end of the hanger bar (10) has a hanging ring (11), and the hanging ring (11) of the hanger bar (10) is welded and fixedly connected to the casing (50) at the borehole opening.

2. The installation structure of the steel cage in the bored pile according to claim 1, characterized in that: Each suspension bar (10) is composed of two three-level ribbed steel bars which are placed side by side and fixedly connected by welding.

3. The installation structure of the steel cage in the bored pile according to claim 1 or 2, characterized in that: The lap length L between the hanger bar (10) and the main bar (21) of the steel cage is 20d.

4. The installation structure of the steel cage in the bored pile according to claim 1 or 2, characterized in that: The number of the suspension bars (10) is three and they are arranged at equal intervals along the circumference of the steel cage (20).

5. The installation structure of the steel cage in the bored pile according to claim 1 or 2, characterized in that: The suspension bar (10) has one end of a suspension ring (11) extending in a direction away from the reinforcement cage (20); and an insertion rod (30) is inserted into the suspension ring (11).

6. The installation structure of the steel cage in the bored pile according to claim 5, characterized in that: The installation structure also includes a sleeper (40) arranged at the opening of the drill hole, the insertion rod (30) is arranged along the radial direction of the steel cage (20), and the two ends of the insertion rod (30) are respectively located on the sleepers (40) on both sides of the drill hole.

7. The installation structure of the steel cage in the bored pile according to claim 1 or 2, characterized in that: The mounting structure further comprises a fixed shaft (60) and a roller (70), wherein the roller (70) is rotatably arranged on the fixed shaft (60), the fixed shaft (60) is fixedly connected to the steel cage (20), the axial direction of the roller (70) is perpendicular to the central axis of the steel cage (20), and when the steel cage (20) is moved downward in the borehole, the roller (70) can roll on the borehole wall.

8. The installation structure of the steel cage in the bored pile according to claim 7, characterized in that: A plurality of barbed teeth (71) are arranged on the outer circumferential surface of the roller (70), and the barbed teeth (71) are arranged at intervals along the circumference of the roller (70). When the barbed teeth (71) on the roller (70) rotate with the roller (70) to contact the wall of the drill hole, the tips of the barbed teeth (71) are tilted upward.

9. The installation structure of the steel cage in the bored pile according to claim 7, characterized in that: The roller (70) is made of concrete, the fixed shaft (60) is made of steel bars, the middle of the fixed shaft (60) is inserted into a through hole in the middle of the roller (70), and the two ends of the fixed shaft (60) are respectively welded to two adjacent main bars of the steel cage (20).

Images