Hollow bolt ball filled with steel fiber concrete grid connection node and manufacturing method

Abstract

The invention discloses a steel fiber concrete grid connection node filled with a hollow bolt ball and a manufacturing method thereof, comprising a grid chord, a hollow bolt ball, a high-strength bolt, a single-sided concave sleeve, a grouting hole, steel fiber concrete and the like; the hollow bolt ball is welded by two hollow hemispheres, threaded holes, grouting holes and exhaust holes are arranged on the hollow bolt ball, the high-strength bolt passes through a cone head and a single-sided concave sleeve and is screwed into the threaded hole of the hollow bolt ball; the single-sided concave sleeve and the high-strength bolt are connected by a pin; the high-strength bolt is driven to rotate by rotating the single-sided concave sleeve and is screwed into the threaded hole of the hollow bolt ball; the grouting pipe and the exhaust pipe end are provided with external threads and are tightened on the hollow bolt ball, the grouting pipe is provided with a switch valve, and the exhaust pipe outlet height exceeds the highest position of the spherical surface; the steel fiber concrete is filled in the hollow bolt ball through the grouting hole through the grouting pipe, the grouting is stopped after the concrete overflows from the exhaust pipe, and the grouting pipe valve is closed.

Description

Technical Field

[0001] The invention relates to the technical field of bolt ball grids, and in particular to a grid connection node filled with steel fiber concrete in a hollow bolt ball and a manufacturing method thereof. Background Art

[0002] With the development of the construction industry, space grid structures have been widely used in various large-span venue buildings. At present, the commonly used grid node forms are hollow welded ball nodes and bolted ball nodes. Welded ball nodes require on-site construction, and the amount of on-site welding is large. Once the node is damaged, the entire system will be difficult to continue to use, and there are many construction disadvantages. Using bolted ball nodes for connection in grid structures can achieve a high level of standardization and assembly, and the bolt ball also has good mechanical properties. However, the bolt ball nodes used in the current project include solid bolt balls and hollow bolt balls. Due to weight restrictions, solid bolt balls cannot be made into larger bolt balls, which limits the number of connecting rods. For hollow bolt balls, in order to meet the strength requirements of the threaded holes, the ball wall thickness needs to be increased; at the same time, when the ball is under pressure, in order to ensure the stability of the ball wall under pressure, the ball wall thickness also needs to be increased, resulting in an increase in the amount of node ball material and reduced economic performance.

[0003] Patent CN102002981A discloses a steel hemisphere internal concrete node and a construction method thereof. The node member is composed of a buckled shell-shaped steel hemisphere, a circular bottom plate, a steel column connected to the lower building structure, and a corbel connected to the upper building structure. One end of the corbel is welded to the outer periphery of the shell of the shell-shaped steel hemisphere, and the other end is connected to the upper building structure. The bottom surface of the shell-shaped steel hemisphere is welded with a circular bottom plate, and a pouring hole is opened in the center of the circular bottom plate. Concrete is poured inside the shell of the shell-shaped steel hemisphere through the pouring hole. Although the patent discloses a technical solution for pouring concrete in a hollow sphere, since the corbel is welded to the shell-shaped steel hemisphere, the concrete only serves to increase the strength of the shell-shaped steel hemisphere, and has no effect on the corbel. In addition, the amount of on-site welding is large. Once the node is damaged, the entire system will be difficult to continue to use, and there are many construction disadvantages. Summary of the invention

[0004] In order to solve the problems existing in the background technology, the present invention discloses a hollow bolt ball filled with steel fiber concrete grid connection node and a manufacturing method; the present invention proposes a bolt ball node with steel fiber concrete filled in the hollow ball, the internal steel fiber concrete not only improves the compressive stable bearing capacity of the hollow ball, reduces the ball wall thickness, and reduces the material consumption, but also provides a certain anchoring force for the high-strength bolts connected thereto.

[0005] In order to achieve the above object, the technical solution adopted by the present invention is as follows:

[0006] In the first aspect, the present invention proposes a hollow bolt ball filled with steel fiber concrete grid connection node form, including a hollow bolt ball, a threaded hole, a high-strength bolt, a single-sided concave sleeve, and steel fiber concrete; the hollow bolt ball is welded by two hollow hemispheres, and a threaded hole grouting hole and an exhaust hole are arranged on the hollow bolt ball. The high-strength bolt passes through a rod, and the single-sided concave sleeve cooperates with the threaded hole of the hollow bolt ball. The high-strength bolt is tightly matched with the threaded hole of the hollow bolt ball by rotating the single-sided concave sleeve, and the single-sided concave sleeve is connected to the high-strength bolt by a pin; steel fiber concrete is filled in the hollow bolt ball through the grouting hole; the internal steel fiber concrete provides an anchoring force for the bolt, while improving the compressive stable bearing capacity of the hollow ball, reducing the ball wall thickness, and reducing material consumption.

[0007] As a further technical solution, the threaded holes are opened in non-welded parts of the hollow bolt ball according to the number of rods in actual engineering.

[0008] As a further technical solution, the concave side of the single-sided concave sleeve is in close contact with the hollow bolt ball, and the sleeve hole is aligned with the threaded hole on the hollow bolt ball.

[0009] As a further technical solution, the thickness of the hollow bolt ball is ≥1.1 times the diameter of the high-strength bolt, and the material of the hollow bolt ball is not lower than Q355B steel.

[0010] As a further technical solution, the concave curvature of the single-sided concave sleeve is equal to the outer curvature of the hollow bolt ball wall, so that the single-sided concave sleeve fits tightly with the hollow bolt ball, reducing stress concentration.

[0011] As a further technical solution, the hollow bolt ball is punched out by a mold of corresponding radius, and two hemispheres are welded together, and the specific welding method is not limited.

[0012] As a further technical solution, the diameter of the grouting hole should be larger than the particle size of the steel fiber concrete aggregate.

[0013] As a further technical solution, the thickness of the hollow hemisphere is determined according to engineering requirements.

[0014] As a further technical solution, an exhaust pipe is installed at the exhaust hole, and the height of the exhaust pipe outlet exceeds the highest position of the spherical surface; in a second aspect, the present invention also provides a method for manufacturing a hollow bolt ball filled with steel fiber concrete grid connection node, comprising the following steps:

[0015] S1. Use a stamping die with corresponding radius to stamp out two hollow hemispheres;

[0016] S2. Align and weld the two hollow hemispheres into a hollow bolt ball, and grind the weld to make it smooth;

[0017] S3. Drill threaded holes, grouting holes and vent holes at non-welding locations on the hollow bolt ball;

[0018] S4. Pass the threaded end of the high-strength bolt through the rod, the sleeve hole and the threaded hole of the hollow bolt ball in sequence, and rotate the single-side concave sleeve to connect the rod and the hollow bolt ball together, and the end of the high-strength bolt extends to a section inside the hollow bolt ball;

[0019] S5. Install the grouting pipe and exhaust pipe. Inject steel fiber concrete through the grouting pipe. After the concrete overflows from the exhaust pipe, close the grouting pipe valve.

[0020] S6. After the initial setting of the concrete, remove the grouting pipe and exhaust pipe, and screw the closing bolts into the grouting holes and exhaust holes.

[0021] In a third aspect, the present invention also provides a method for manufacturing a hollow bolt ball filled with steel fiber concrete grid connection node, comprising the following steps:

[0022] S1. Use a drilling machine to drill grouting holes and exhaust holes of a certain size on the hollow bolt ball according to actual needs;

[0023] S2. Install the grouting pipe and exhaust pipe. Inject steel fiber concrete through the grouting pipe. After the concrete overflows from the exhaust pipe, close the grouting pipe valve.

[0024] S3. After the initial setting of the concrete, remove the grouting pipe and exhaust pipe, and screw the closing bolts into the grouting holes and exhaust holes.

[0025] S4, using a drilling machine to drill a set number of threaded holes in the steel fiber-filled concrete hollow bolt ball;

[0026] S5. Pass the high-strength bolt with the pin notch through the cone head hole of the rod;

[0027] S6. Insert the non-concave surface of the single-sided concave sleeve from the threaded end of the high-strength bolt, align the limiting hole of the single-sided concave sleeve with the pin slot on the high-strength bolt, insert the fastening pin to connect, and then insert the threaded end of the high-strength bolt into the threaded hole on the hollow bolt ball, and rotate the single-sided concave sleeve to drive the high-strength bolt to rotate through the fastening pin, and gradually screw it into the hollow bolt ball and steel fiber concrete to achieve the installation of the rod and the hollow bolt ball.

[0028] Compared with the traditional structure, the present invention has the following beneficial effects:

[0029] 1. The hollow bolt ball joint proposed by the present invention reduces the steel consumption of the structure compared with the solid bolt ball joint.

[0030] The invention can save economic costs; the hollow bolt ball is adopted in the present invention, and the length of the bolt penetrating into the ball is not limited, which solves the potential safety hazard caused by the inability of the bolt to be completely screwed into the hole when the blind hole of the traditional solid ball is not deep enough; and the steel fiber concrete filled in the hollow bolt ball node of the present invention is lighter than the steel material of the same volume, which is conducive to making a bolt ball of large volume; at the same time, the toughness and crack resistance of the steel fiber concrete are utilized to improve the bearing capacity and rigidity of the hollow bolt ball; and the internal steel fiber concrete not only provides the anchoring force for the bolt, but also improves the compressive stable bearing capacity of the hollow ball, reduces the ball wall thickness, and reduces the material consumption.

[0031] 2. The present invention solves the problem that the nut cannot be screwed inside the closed sphere to fix the high-strength bolt by providing a single-side concave sleeve as a rotation auxiliary part. In addition, the present invention avoids the problem of reduced strength of the sphere wall caused by turning the sphere into a plane by increasing the contact area between the single-side concave sleeve and the sphere wall.

[0032] 3. In one of the manufacturing methods proposed in the present invention, the high-strength bolt of the rod is first inserted into the hollow bolt ball, and the end portion of the high-strength bolt extends to a section inside the hollow bolt ball, and then steel fiber concrete is injected. The advantage of this implementation is that the position of the high-strength bolt in the hollow bolt ball can be further fixed by the steel fiber concrete, and the connection between the two can be strengthened, thereby making the rod and the hollow bolt ball firmly connected. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 It is a schematic diagram of the overall structure of the present invention;

[0034] Figure 2 A schematic diagram of the connection relationship of various components in an embodiment of the present invention;

[0035] Figure 3 This is a schematic diagram of the connection relationship of various components during grouting in an embodiment of the present invention;

[0036] Figure 4 It is a schematic diagram of the connection cross section of the present invention;

[0037] Figure 5 It is an exploded diagram of the structure of an embodiment of the present invention;

[0038] Figure 6 This is a schematic diagram of a single-side concave sleeve structure according to an embodiment of the present invention;

[0039] Numbers in the figure: 1. Hollow bolt ball; 2. Steel fiber concrete; 3. High-strength bolt; 4. Single-sided concave sleeve; 5. Fastening pin; 6. Rod; 7. Grouting hole; 8. Pin slot; 9. Cone head; 10 Exhaust hole; 11. Grouting pipe; 12. Grouting pipe valve; 13. Exhaust pipe; 14. Sealing bolt. DETAILED DESCRIPTION

[0040] In order to understand the present invention more clearly, the following is a detailed description in conjunction with the accompanying drawings and embodiments. It should be noted that the given embodiment is only one kind of implementation method and does not represent all embodiments. In the absence of conflict, the embodiments of the present application and the features in the embodiments can be combined with each other. Based on the embodiments of the present invention, other embodiments obtained by ordinary technicians in this field without making creative work are all within the scope of protection of the present invention.

[0041] It should be noted that if the embodiments of the present invention involve directional indications (such as up, down, left, right, front, back, etc.), the directional indications are only used to explain the relative position relationship, movement status, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0042] In the present invention, unless otherwise clearly specified and limited, the terms "connection", "fixation", etc. should be understood in a broad sense. For example, "fixation" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0043] In view of the above problems, the present embodiment discloses a method of making a solid bolt ball become a hollow bolt ball filled with steel fiber concrete grid connection node form, which is used to solve the problems raised in the background technology part; the present invention cleverly combines the bolt connection with the hollow bolt ball filled with concrete, solves the problems existing in the solid bolt ball node, the welding node and the problem of the connection between the hollow bolt ball and the bolt, and makes full use of the steel fiber concrete in the hollow bolt ball. The steel fiber concrete inside the high hollow bolt ball can provide an anchoring force for the bolt, which solves the problem that in the prior art, the thickness of the ball wall needs to be increased to meet the strength requirements of the threaded hole; at the same time, when the ball is under pressure, in order to ensure the compressive stability of the ball wall, the thickness of the ball wall also needs to be increased, resulting in an increase in the amount of node ball material used and a decrease in economic performance. At the same time, the compressive stability bearing capacity of the hollow ball is improved by the steel fiber concrete, the ball wall thickness is reduced, and the amount of material used is reduced.

[0044] Embodiment 1:

[0045] Combined with Figure 1-Figure 5 The hollow bolt ball grid connection node filled with steel fiber concrete disclosed in this embodiment includes a hollow bolt ball 1, steel fiber concrete 2, M30 high-strength bolt 3, and a rod 6. The hollow bolt ball 1 is provided with a plurality of threaded holes, a grouting hole 7, and an exhaust hole 10. The threaded end of the M30 high-strength bolt 3 passes through the cone head hole of the rod 6. The high-strength bolt 3 is screwed into the first internal threaded hole of the hollow bolt ball 1 by rotating the auxiliary part, so that the rod and the hollow bolt ball are fastened by thread connection. The steel fiber concrete 2 is injected into the hollow bolt ball 1 through the grouting hole 7, and the steel fiber concrete is cured to the service strength; the grouting pipe 11 and the exhaust pipe 13 end plates are provided with external threads, which are tightened on the grouting hole 7 and the exhaust hole 10 on the hollow bolt ball, and the grouting pipe 11 is provided with a switch valve, and the outlet height of the exhaust pipe 13 exceeds the highest point of the spherical surface by no less than the radius of the ball; the hollow bolt ball is filled with steel fiber concrete through the grouting hole through the grouting pipe 11, and the grouting is stopped after the concrete overflows from the exhaust pipe, and the grouting pipe valve is closed.

[0046] The hollow bolt ball node proposed by the present invention reduces the amount of steel used in the structure compared to the solid bolt ball node disclosed in the prior art, which can save economic costs; at the same time, the steel fiber concrete filled in the hollow bolt ball node of the present invention is lighter than the steel of the same volume, which is conducive to making a large volume of bolt balls; at the same time, the toughness and crack resistance of steel fiber concrete are utilized to improve the bearing capacity and rigidity of the hollow bolt ball. The steel fiber concrete inside the high hollow bolt ball not only provides anchoring force for the bolt, but also improves the compressive stable bearing capacity of the hollow ball, reduces the ball wall thickness, and reduces the amount of material used.

[0047] Specifically, Figure 3 As shown, the hollow bolt ball 1 in this embodiment is formed by welding two hollow hemispheres of a certain thickness, and the hollow bolt ball 1 is filled with steel fiber concrete 2.

[0048] Further, such as Figure 5 As shown, the above-mentioned rotation auxiliary part includes a single-sided recessed sleeve 4 and a fastening pin 5. A limiting hole is radially opened on one side of the single-sided recessed sleeve 4, and a pin slot 8 is axially opened on the side wall of the high-strength bolt 3. The single-sided recessed sleeve 4 is arranged on the outer wall of the threaded end of the high-strength bolt 3, and the fastening pin 5 is passed through the limiting hole. One end of the fastening pin 5 close to the high-strength bolt 3 extends into the pin slot 8, and the fastening pin 5 is in sliding contact and connection with the pin slot 8, so that the single-sided recessed sleeve 4 is connected to the high-strength bolt 3 to form a whole.

[0049] The main reason for setting a rotation auxiliary part in the present invention is to facilitate screwing the high-strength bolt into the hollow bolt ball. The hollow bolt ball 1 in this embodiment is welded by two hollow hemispheres of a certain thickness, that is, before being installed on the high-strength bolt 3, the hollow bolt ball 1 has become a closed sphere. Therefore, it is impossible to screw a nut inside the closed sphere to fix the high-strength bolt 3. In order to solve this problem, the present invention adopts a single-sided concave sleeve 4 as a rotation auxiliary part to achieve the tightening of the high-strength bolt 3 on the hollow bolt ball 1.

[0050] Furthermore, the concave side of the single-sided concave sleeve 4 is tightly against the hollow bolt ball, and the sleeve hole is aligned with the threaded hole on the hollow bolt ball; the concave curvature of the single-sided concave sleeve is equal to the outer curvature of the hollow bolt ball wall, so that the single-sided concave sleeve fits tightly against the hollow bolt ball, reducing stress concentration.

[0051] Specifically, the threaded holes on the hollow bolt ball 1 are opened at the non-welding position of the hollow bolt ball according to the number of rods in the actual project.

[0052] As a further technical solution, the thickness of the hollow hemisphere is taken according to the engineering needs. For example, the thickness of the hollow bolt ball is ≥ 1.1 times the diameter of the high-strength bolt. The purpose of this design is mainly to ensure that there is sufficient connection strength between the two, and the material of the hollow bolt ball is not lower than Q355B steel.

[0053] As a further technical solution, the hollow bolt ball is punched out by a mold of corresponding radius, and two hemispheres are welded together, and the specific welding method is not limited.

[0054] As a further technical solution, the diameter of the grouting hole 7 should be larger than the particle size of the steel fiber concrete aggregate, so that the steel fiber concrete aggregate can smoothly enter the hollow bolt ball.

[0055] As a further technical solution, an exhaust pipe is installed at the exhaust hole, and the height of the exhaust pipe outlet exceeds the highest position of the spherical surface.

[0056] Furthermore, this embodiment also provides a method for manufacturing a hollow bolt ball grid node filled with steel fiber concrete, comprising the following steps:

[0057] S1. Use a stamping die with corresponding radius to stamp out two hollow hemispheres;

[0058] S2. Align and weld the two hollow hemispheres into a hollow bolt ball, and grind the weld to make it smooth;

[0059] S3. Drill threaded holes, grouting holes, and exhaust holes at non-welding locations on the hollow bolt ball;

[0060] S4. Pass the threaded end of the high-strength bolt through the rod, the sleeve hole and the threaded hole of the hollow bolt ball in sequence, and rotate the single-side concave sleeve to connect the rod and the hollow bolt ball together, and the end of the high-strength bolt extends to a section inside the hollow bolt ball;

[0061] S5. Install a grouting pipe and an exhaust pipe at the grouting hole and the exhaust hole respectively, and inject steel fiber concrete through the grouting pipe; after the concrete overflows from the exhaust pipe, close the grouting pipe valve;

[0062] S6. After the initial setting of the concrete, remove the grouting pipe and exhaust pipe, and screw the closing bolts into the grouting holes and exhaust holes.

[0063] In the above manufacturing method, the high-strength bolt 3 of the rod is first inserted into the hollow bolt ball, and the end portion of the high-strength bolt 3 extends to a section inside the hollow bolt ball, and then steel fiber concrete is injected. The advantage of this implementation is that the position of the high-strength bolt 3 in the hollow bolt ball can be further fixed by the steel fiber concrete, and the connection between the two can be strengthened, thereby making the rod and the hollow bolt ball firmly connected.

[0064] Embodiment 2:

[0065] The hollow bolt ball grid connection node structure filled with steel fiber concrete disclosed in this embodiment is exactly the same as that in the first embodiment, except that the manufacturing method is different, as follows:

[0066] S1. Use a drilling machine to drill grouting holes and exhaust holes of a certain size on the hollow bolt ball according to actual needs;

[0067] S2. Install the grouting pipe and exhaust pipe. Inject steel fiber concrete through the grouting pipe. After the concrete overflows from the exhaust pipe, close the grouting pipe valve.

[0068] S3. After the initial setting of the concrete, remove the grouting pipe and the exhaust pipe, and screw the closing bolts into the grouting holes and the exhaust holes.

[0069] S4, using a drilling machine to drill a set number of through holes in the steel fiber-filled concrete hollow bolt ball;

[0070] S5. Pass the high-strength bolt with the pin notch through the cone head hole of the rod;

[0071] S6. Insert the non-concave surface of the single-sided concave sleeve from the threaded end of the high-strength bolt, align the limiting hole of the single-sided concave sleeve with the pin slot on the high-strength bolt, insert the fastening pin to connect, and then insert the threaded end of the high-strength bolt into the first internal threaded hole on the hollow bolt ball, and rotate the single-sided concave sleeve to drive the high-strength bolt to rotate through the fastening pin, and gradually screw it into the hollow bolt ball to achieve the installation of the rod and the hollow bolt ball.

[0072] The hollow bolt ball grid connection node produced by the above method is less firm than the hollow bolt ball grid connection node produced in Example 1, but compared with Implementation 1, on-site grouting can be avoided. After the grouting prefabrication in the factory is completed, it is transported to the construction site for installation, which can improve the construction efficiency and assembly level of the project.

[0073] The above description is only a preferred embodiment of the present invention, and does not limit the patent scope of the present invention. All equivalent structural changes made by using the contents of the present invention specification and drawings under the inventive concept of the present invention, or directly / indirectly applied in other related technical fields are included in the patent protection scope of the present invention.

Claims

1. A hollow bolt ball filled with steel fiber concrete grid connection node, characterized in that: Including empty A hollow bolt ball, a threaded hole, a high-strength bolt, a single-side concave sleeve, a rod, a grouting hole and steel fiber concrete; the hollow bolt ball is welded by two hollow hemispheres, a threaded hole, a grouting hole and an exhaust hole are arranged on the hollow bolt ball, the high-strength bolt passes through the rod, the single-side concave sleeve is matched with the threaded hole of the hollow bolt ball, the high-strength bolt is fastened with the threaded hole of the hollow bolt ball by rotating the single-side concave sleeve, and the single-side concave sleeve and the high-strength bolt are connected by a pin; the hollow bolt ball is filled with steel fiber concrete through the grouting hole, and the steel fiber concrete provides an anchoring force for the high-strength bolt; The concave side of the single-sided concave sleeve is in close contact with the hollow bolt ball, and the sleeve hole is aligned with the threaded hole on the hollow bolt ball. The curvature of the concave surface of the single-sided concave sleeve is equal to the curvature of the outer side of the hollow bolt ball wall. Grouting holes and exhaust holes are respectively equipped with grouting pipes and exhaust pipes; First, pass the threaded end of the high-strength bolt through the rod, sleeve hole and threaded hole of the hollow bolt ball in sequence, rotate the single-sided concave sleeve to connect the rod and the hollow bolt ball together, and the length of the high-strength bolt extending into the hollow bolt ball should not be less than the bolt diameter, then inject steel fiber concrete through the grouting pipe, and close the grouting pipe valve after the concrete overflows from the exhaust pipe; The threaded holes are opened at non-welding positions of the hollow bolt balls according to the number of rods in actual engineering.

2. The hollow bolt ball filled with steel fiber concrete grid connection node as claimed in claim 1, characterized in that: The thickness of the hollow bolt ball ≥ 1.1 times the diameter of the high-strength bolt, the material of the hollow bolt ball is not less than Q355B steel.

3. The hollow bolt ball filled with steel fiber concrete grid connection node as claimed in claim 1, characterized in that: The hollow bolt ball is punched out by a die with a corresponding radius, and two hemispheres are welded together.

4. The hollow bolt ball filled with steel fiber concrete grid connection node as claimed in claim 1, characterized in that: The aperture of the grouting hole should be larger than the particle size of the steel fiber concrete aggregate.

5. The hollow bolt ball filled with steel fiber concrete grid connection node as claimed in claim 1, characterized in that: An exhaust pipe is installed at the exhaust hole, and the exhaust pipe outlet height exceeds the highest position of the spherical surface.

6. A method for manufacturing a hollow bolt ball filled with steel fiber concrete grid connection node as claimed in any one of claims 1 to 5, characterized in that: The following steps are involved: S1. Use a stamping die with corresponding radius to stamp out two hollow hemispheres; S2. Align and weld the two hollow hemispheres into a hollow bolt ball, and grind the weld to make it smooth; S3. Drill threaded holes, grouting holes and vent holes at non-welding locations on the hollow bolt ball; S4. Pass the threaded end of the high-strength bolt through the rod, the sleeve hole and the threaded hole of the hollow bolt ball in sequence, rotate the single-sided concave sleeve to connect the rod and the hollow bolt ball together, and the length of the high-strength bolt extending into the hollow bolt ball is not less than the bolt diameter; S5. Install the grouting pipe and exhaust pipe, inject steel fiber concrete through the grouting pipe, and close the grouting pipe valve after the concrete overflows from the exhaust pipe; S6. After the initial setting of the concrete, remove the grouting pipe and exhaust pipe, and screw the closing bolts into the grouting holes and exhaust holes.

Images