Short-limb upset head steel pipe soil nail for slope support

Abstract

The utility model discloses a short-limb upset head steel pipe soil nail for slope support, which comprises a steel pipe, slurry outlet holes arranged on the steel pipe, helical blades welded on the surface of the steel pipe, an end sealing plate welded at one end of the steel pipe, staggered drill teeth arranged outside the end sealing plate, and a cutting seam arranged at the end of the steel pipe close to the end sealing plate along the length direction of the steel pipe. And stones are injected into the cutting seams to form upset heads at the ends of the steel pipes. The end portion of the steel pipe is made into a drill bit shape, the steel pipe can be directly screwed into a soil body through an automatic drilling machine, and deformation of the steel pipe caused by mechanical striking is avoided. The pipe body is provided with the spiral blade, so that the slurry outlet hole is not easy to block in the drilling process; the end part of the steel pipe is upset to form an upset head, so that the pulling resistance of the soil nail is increased; upset heads are formed at the ends of the soil nails to increase pulling resistance, short-limb steel pipes can be used, and the length of the steel pipes is effectively shortened.

Description

Technical Field

[0001] The utility model belongs to the technical field of building construction, and particularly relates to a short-leg upset steel pipe soil nail for slope support. Background Technique

[0002] With the urbanization process in China, the construction field has been continuously improved with the industrialized production mode, and geotechnical engineering such as foundation pit slope support in construction projects has also developed rapidly. The original traditional support methods cannot meet the requirements of construction projects for quality, efficiency and environmental protection. The soil nail wall is an in-situ soil reinforcement technology, which reinforces the foundation pit slope through soil nails or steel pipes made of steel bars. A slope reinforcement support construction method is combined with a steel bar mesh laid on the slope surface and then sprayed with a layer of concrete surface layer and an earth slope. Most of the materials used in the soil nail wall are steel, which can enhance the stability of the foundation pit slope, and has economy and environmental protection, and is widely used in slope support. However, in actual projects, the commonly used driven steel pipe soil nail with holes is prone to deformation during the driving process, the slurry outlet holes are easily blocked during the strong driving process, and the anti-pulling force is poor. CN209178993U discloses a spiral grouting steel pipe soil nail. The spiral blades on the outer wall surface of the main pipe body help the soil nail to be directly screwed into the soil without pre-drilling, but the tensile strength of the soil nail is not large. CN216948247U discloses a steel pipe soil nail with a special-shaped spiral anchor. The existing rod-shaped soil nail is divided into two sections. The front end is a spiral anchor, which can be drilled and has an anchoring effect. The rear end is a steel pipe, and the holes on it can be grouted to form an anchor body. The end of the spiral anchor at the front end is thin, resulting in low tensile strength. Summary of the Invention

[0003] Aiming at the problems existing in the prior art that the steel pipe with holes is prone to deformation during the driving process, the slurry outlet holes are easily blocked during the strong driving process, and the anti-pulling force is poor, the utility model provides a short-leg upset steel pipe soil nail for slope support. The pipe body is provided with spiral blades, and the slurry outlet holes are not easily blocked during the drilling process; the end of the soil nail is upset to form an enlarged head, which increases the anti-pulling force of the soil nail.

[0004] The purpose of the utility model is realized in the following way:

[0005] A short-leg upset steel pipe soil nail for slope support includes a steel pipe. The steel pipe is provided with slurry outlet holes, spiral blades are welded on the surface of the steel pipe, a head end sealing plate is welded at one end of the steel pipe, staggered drill teeth are arranged outside the head end sealing plate, a cutting slot along the length direction of the steel pipe is arranged at the end of the steel pipe near the head end sealing plate, and coarse aggregate is injected into the cutting slot to form an upset head at the end of the steel pipe.

[0006] The slurry outlet holes are arranged in a plum blossom shape on the surface of the steel pipe.

[0007] The length of the cutting slot is 100-200mm, the interval is 10-20mm, and the cutting slot is 10-20mm away from the head end sealing plate.

[0008] The bottom side length of the drill bit teeth is 10 - 15 mm, and the height is 10 - 15 mm.

[0009] Compared with the prior art, the utility model makes the end of the steel pipe into a drill bit shape, and the steel pipe can be directly screwed into the soil by using an automatic drilling machine, avoiding the deformation of the steel pipe caused by mechanical impact; the pipe body is provided with spiral blades, and the slurry outlet holes are not easy to be blocked during the drilling process; the end of the steel pipe is upset to form a upset head, increasing the anti-pulling force of the soil nail; the end of the soil nail forms a upset head to increase the anti-pulling force, and short-limbed steel pipes can be used, effectively shortening the length of the steel pipe. Description of the Drawings

[0010] Figure 1 is a schematic structural view of the utility model. Detailed Embodiments

[0011] The following further elaborates the utility model in conjunction with the drawings and specific embodiments. It should be understood that these embodiments are only used to illustrate the utility model and are not used to limit the scope of the utility model. After reading the content of the utility model, those skilled in the art can make various changes or modifications to the utility model, and these equivalent forms also fall within the scope defined by the utility model.

[0012] As Figure 1 shown, a short-limbed upset head steel pipe soil nail for slope support includes a steel pipe 1, slurry outlet holes 4 are arranged on the steel pipe 1, spiral blades 5 are welded on the surface of the steel pipe 1, an end head sealing plate 2 is welded at one end of the steel pipe, staggered drill bit teeth 6 are arranged outside the end head sealing plate 2, a cutting seam 3 along the length direction of the steel pipe is arranged near the end of the steel pipe close to the end head sealing plate 2, and coarse aggregate, preferably stones, is injected into the cutting seam 3 to form a upset head at the end of the steel pipe. More specifically, first load an appropriate amount of stones into the steel pipe, and then use a mechanical piston to quickly push the stones into the end of the steel pipe, making the cutting seam part at the end of the steel pipe upset to form an enlarged head. Finally, inject cement slurry from the end of the steel pipe to form a short-limbed upset head steel pipe soil nail.

[0013] Further preferred scheme, the slurry outlet holes 4 are arranged in a plum blossom shape on the surface of the steel pipe 1.

[0014] Further preferred scheme, the bottom side length of the drill bit teeth 6 is 10 - 15 mm, and the height is 10 - 15 mm.

[0015] Further preferred scheme, the length of the cutting seam 3 is 100 - 200 mm, the interval is 10 - 20 mm, and the cutting seam 3 is 10 - 20 mm away from the end head sealing plate.

[0016] A preferred embodiment is as follows: Select a steel pipe 1 with a length of 6 m and a diameter of Φ60 as the pipe body of the short-leg headed steel pipe soil nail (the length and diameter can be adjusted according to the design); Cut one end of the steel pipe 1 into drill bit teeth 6 with a bottom side length of 15 mm and a height of 15 mm; Weld an end sealing plate 2 inside the drill bit teeth 6 to block the bottom of the steel pipe 1 to prevent leakage of stones or cement slurry, etc.; At a distance of 20 mm from the sealing plate, cut multiple vertical slits along the length direction of the steel pipe 1. The intervals between the multiple cutting slits are 15 mm, and the cutting slits are 150 mm long; Drill grouting holes 4 on the steel pipe 1, and the hole positions of the grouting holes 4 are arranged in a plum blossom shape; Weld small leaf spiral blades 5 vertically along the steel pipe, and use an automatic drilling machine to screw the steel pipe 1 into the foundation pit slope soil body; Load an appropriate amount of stones into the steel pipe, and use a mechanical piston to quickly push the stones into the end of the steel pipe to thicken the cutting slit 3 part at the end of the steel pipe to form an enlarged head; Inject cement slurry from the end of the steel pipe to form a short-leg headed steel pipe soil nail. The injected cement slurry flows out from the grouting holes 4 to achieve a firm combination with the soil, so that the short-leg headed steel pipe soil nail is firmly fixed on the wall to protect the stability of the soil body on the side wall of the foundation pit.

[0017] The utility model makes the end of the steel pipe into a drill bit shape, and an automatic drilling machine can be used to directly screw the steel pipe into the soil body to avoid the deformation of the steel pipe caused by mechanical impact; The pipe body is equipped with spiral blades, and the grouting holes are not easily blocked during the drilling process; The end of the steel pipe is thickened to form a headed part, which increases the uplift resistance of the soil nail; The headed part is formed at the end of the soil nail to increase the uplift resistance, and short-leg steel pipes can be used to effectively shorten the length of the steel pipe.

[0018] The short-leg headed steel pipe soil nails for slope support play an important role in modern geotechnical engineering with their unique structural characteristics, construction advantages and wide application fields. With the continuous progress of technology and the drive of market demand, the short-leg headed perforated pipe soil nail technology will continue to maintain a rapid development trend, providing a strong guarantee for urban construction and underground space development.

[0019] The above are only the preferred embodiments of the utility model. It should be pointed out that for those skilled in the art, without departing from the overall concept of the utility model, several changes and improvements can still be made, and these should also be regarded as the protection scope of the utility model.

Claims

1. A short-limbed steel pipe soil nail for slope support, characterized in that: The invention comprises a steel pipe (1), a slurry outlet hole (4) is arranged on the steel pipe (1), a spiral blade (5) is welded on the surface of the steel pipe (1), an end sealing plate (2) is welded at one end of the steel pipe, staggered drill teeth (6) are arranged outside the end sealing plate (2), a cutting seam (3) along the length direction of the steel pipe is arranged at the end of the steel pipe near the end sealing plate (2), and coarse aggregate is injected into the cutting seam (3) to form a head at the end of the steel pipe.

2. According to claim 1, the short-limbed steel pipe soil nail for slope support is characterized in that: The slurry outlet holes (4) are arranged in a plum blossom shape on the surface of the steel pipe (1).

3. The short-limb upsetting steel pipe soil nail for slope support according to claim 1, characterized in that: The length of the cutting slit (3) is 100-200 mm, the interval is 10-20 mm, and the distance between the cutting slit (3) and the end sealing plate (2) is 10-20 mm.

4. The short-limb upsetting steel pipe soil nail for slope support according to claim 1, characterized in that: The bottom side of the drill teeth (6) is 10-15 mm long and 10-15 mm high.

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