CN107905455A - A kind of grouting sleeve for prefabricated concrete component reinforcement connection and preparation method thereof - Google Patents

Abstract

The invention relates to a grouting sleeve for prefabricated concrete member steel bar connection, comprising a seamless steel tube, the two ends of the seamless steel tube are provided with grouting nozzles, the two ends of the seamless steel tube are used for inserting connecting steel bars, the seamless steel tube The inner wall of the seamless steel pipe is provided with internal threads, and wedge-shaped bodies are embedded in both ports of the seamless steel pipe. The invention welds wedge-shaped bodies at both ends of the grouting sleeve to constrain the high-strength grouting material so that no wedge-shaped spalling damage occurs when the connecting steel bar is stressed, and strengthens the bonding between the high-strength grouting material and the steel bar, so that the overall performance of the grouting sleeve is improved. greatly improved. The inner wall of the seamless steel pipe is provided with an internal thread, and a small pitch and a small thread depth are used to reduce the thickness of the seamless steel pipe material and enhance the bonding between the high-strength grouting material and the grouting sleeve. The internal thread and wedge body are processed by CNC machine tools, which is efficient, simple and convenient.

Description

A kind of grouting sleeve for prefabricated concrete component reinforcement connection and preparation method thereof

technical field

The invention relates to the technical field of construction engineering, in particular to a grouting sleeve for connecting prefabricated concrete components to steel bars and a preparation method thereof.

Background technique

At present, the prefabricated building structure is one of the key structural forms in the process of housing industrialization and industrialization in my country. It has the advantages of high efficiency, low energy consumption and environmental protection, which are in line with the current social and economic development. Prefabricated buildings have a high degree of industrialization. The components are prefabricated in special prefabrication factories, and then transported to the site for assembly after scientific and reasonable maintenance. It is similar to the assembly mode of "building blocks", but structural integrity is the most important part of the durability of prefabricated buildings. One of the measurement indicators, so the key point of its technology is the connection between components.

The connection of components in the prefabricated concrete structure is mainly the connection of steel bars. There are two main methods: the first is the connection of steel grout anchors, which refers to inserting the holes that need to be overlapped in the channels made by special processes in prefabricated concrete components. Steel bars, and the steel bar lap joint connection method realized by pouring cement-based grouting materials, is mostly used in wall panel structures. The other is the steel bar sleeve grouting connection, which refers to the steel bar butt joint connection method realized by inserting steel bars into the pre-embedded metal sleeves in precast concrete components and pouring cement-based grouting materials.

At present, grouting sleeve connection is the preferred choice for steel bar connection in the relevant codes and regulations of prefabricated concrete structures in various parts of my country. The reason is that compared with the grout-anchor connection, the grouting sleeve connection has higher reliability of the stressed reinforcement. When the grouting sleeve is applied to the connection of the steel bars of the vertical members in the prefabricated concrete structure, the prefabricated end steel bar is inserted into one end of the grouting sleeve in the prefabrication factory, and is pre-buried at the bottom of the vertical prefabricated concrete member. The steel bar reserved for another prefabricated concrete component is inserted into the other end of the grouting sleeve, and then the high-strength non-shrinkage grouting material is injected from the grouting nozzle. Grouting sleeves can also be used for horizontal reinforcement connections between precast concrete elements.

Grouting sleeves can be divided into ductile iron sleeves and machined sleeves. Ductile iron sleeves need to use high-strength and high-toughness cast steel materials and precision casting processes, which are prone to casting defects and require a large number of molds, so the cost is high; the outer concave and inner convex fully grouted steel sleeves processed by interval ring cutting, It has a large amount of cutting and processing, requires very thick steel pipe raw materials, and requires a long length when used, so the cost is relatively high; for the two steel bars connected, one is connected by a slurry anchor, and the other is a semi-grouting cast steel bar connected by a straight thread. Steel sleeves or cylindrical semi-grouted steel sleeves with bottoms processed by cutting, the cast steel sleeves are prone to casting defects, and the steel sleeves processed from round steel require thick steel pipes for cutting, which wastes materials and requires a lot of work , These all lead to an increase in processing and manufacturing costs, and there is not much advantage in use performance, which also affects the large-scale promotion and application of the project.

Chinese patent document CN201320407071 discloses a grouted deformed steel pipe sleeve for butt-connected steel grout anchors, the grouted deformed steel pipe sleeve is directly made by sawing seamless steel pipe; the outer surface of the seamless steel pipe is formed by rolling There are multiple radial inverted trapezoidal grooves, and the inner surface of the seamless steel pipe at the same position as the grooves has arc-shaped convex ring ribs formed by protruding following the deformation of the rolling grooves. The sleeve is simple to manufacture, but the grouting material at the end tends to peel off in a conical shape when the connecting steel bar is super strong, which will cause the steel bar to be pulled out during an earthquake and cause construction danger.

To sum up, the existing grouting sleeves have disadvantages such as bulky form, large volume, high cost and time-consuming and material-consuming processing, which is not conducive to the development of prefabricated buildings. Therefore, it is necessary to develop a grouting sleeve with reasonable structure, simple manufacture and excellent performance, which can ensure that the connecting steel bar and the grouting material will not be pulled out under the condition of super strong steel bar and repeated earthquake action.

Contents of the invention

The technical problem to be solved by the present invention is to provide a grouting sleeve for connecting prefabricated concrete members to steel bars and a preparation method thereof, which can not only enhance the bonding between the high-strength grouting material and the grouting sleeve, It can also greatly improve the overall performance of the grouting sleeve joint.

The technical scheme that the present invention adopts for solving the technical problem of above-mentioned proposal is:

A grouting sleeve for prefabricated concrete member steel bar connection, comprising a seamless steel tube, the two ends of the seamless steel tube are provided with grouting nozzles, the two ends of the seamless steel tube are used for inserting connecting steel bars, the The inner wall of the seamless steel pipe is provided with internal threads, wedge-shaped bodies are embedded in both ports of the seamless steel pipe, the thick ends of the wedge-shaped bodies are close to the ports, and the two ports of the seamless steel pipe are provided with connecting steel bars Fitting sealing plug.

In the above solution, the thickest end of the wedge is 5mm away from the port of the seamless steel pipe.

In the above solution, the wedge-shaped body is annular, the outer diameter of the wedge-shaped body is equal to the inner diameter of the seamless steel pipe, the wedge-shaped body is welded to the seamless steel pipe, and the thickness of the thinnest end of the wedge-shaped body is 1mm ~1.5mm.

In the above solution, the distance between the nozzles at both ends of the seamless steel pipe is 10-15mm from the ports, one end of the nozzle is connected to the outside world, and the other end runs through the pipe wall and the wedge-shaped nozzle along the radial direction of the seamless steel pipe. The back of the body communicates with the inner cavity of the seamless steel pipe.

In the above solution, the middle part of the seamless steel pipe is radially provided with a limit pin, and both ends of the limit pin are welded to the inner wall of the seamless steel tube.

In the above solution, the internal thread is distributed symmetrically with respect to the limit pin, the outer end of the internal thread extends longest to the thinnest end of the wedge, and the inner end of the internal thread extends longest to the distance from the 15mm from the limit pin.

In the above solution, the pitch of the internal thread is 2 mm to 4 mm, and the thread depth is 1.5 to 3.5 mm.

In the above solution, the sealing plug is made of rubber, and the sealing plug is in interference fit with the connecting steel bar.

In the above solution, the material of the seamless steel pipe and the wedge body is ordinary carbon steel or high-quality carbon structural steel or low-alloy high-strength steel.

The present invention also proposes a preparation method for the grouting sleeve for the connection of the above-mentioned prefabricated concrete member reinforcement, comprising the following steps:

The first step is to select a seamless steel pipe with an appropriate wall thickness and diameter according to the diameter of the connecting steel bar, and then cut the appropriate length with an electric saw;

In the second step, the internal thread of the seamless steel pipe is turned by using a CNC machine tool;

The third step is to select a seamless steel pipe with a suitable wall thickness and an outer diameter equal to the inner diameter of the seamless steel pipe and turn it into a wedge-shaped body with a CNC machine tool;

The fourth step is to put the wedge-shaped body into the two ends of the seamless steel pipe that has been processed with internal threads, and the side with thicker wall thickness is close to the end of the seamless steel pipe, and then weld the seamless steel pipe and the wedge-shaped body to form a welded joint. seam

The fifth step is to drill a hole in the middle of the seamless steel pipe, insert a limit pin, and then spot weld the seamless steel pipe at both ends of the limit pin;

The sixth step is to drill a hole at both ends of the seamless steel pipe and weld the grout nozzle.

The beneficial effects of the present invention are:

1. By welding wedge-shaped bodies at both ends of the grouting sleeve to restrain the high-strength grouting material so that it does not produce wedge-shaped spalling damage when the connecting steel bar is stressed, and to enhance the bond between the high-strength grouting material and the steel bar, the overall performance of the grouting sleeve greatly improved.

2. The inner wall of the seamless steel pipe is provided with internal threads, and the small pitch and small thread depth are used to reduce the thickness of the seamless steel pipe material and enhance the bonding between the high-strength grouting material and the grouting sleeve.

3. The internal thread and wedge body are processed by CNC machine tools, which is high in efficiency, simple and convenient.

4. The raw materials of seamless steel pipes and wedges are easy-to-obtain ordinary carbon steel, high-quality carbon structural steel or low-alloy high-strength steel.

Description of drawings

The present invention will be further described below in conjunction with accompanying drawing and embodiment, in the accompanying drawing:

Fig. 1 is a schematic diagram of a joint formed by inserting connecting steel bars into both sides of the grouting sleeve of the present invention and pouring into high-strength non-shrinkage grouting material;

Fig. 2 is A-A sectional view of Fig. 1;

Fig. 3 is a schematic diagram of a wedge-shaped body of the grouting sleeve shown in Fig. 1;

Fig. 4 is the schematic diagram of the butt joint connection of the prefabricated shear wall reinforcement using the grouting sleeve of the present invention;

Fig. 5 is the B-B sectional view of Fig. 4;

Fig. 6 is a schematic diagram of the butt joint connection between the precast concrete column and the steel bar of the precast concrete column using the grouting sleeve of the present invention;

Fig. 7 is a schematic diagram of the butt joint connection between the precast concrete column and the precast concrete beam reinforcement using the grouting sleeve of the present invention.

In the figure: 100, grouting sleeve; 10, seamless steel pipe; 11, internal thread; 12, grout injection nozzle; 20, wedge; 30, weld; 40, limit pin; 50, sealing plug; 200, Connecting reinforcement; 300, non-shrinkage grouting material; 401, upper precast shear wall; 402, lower precast shear wall; 403, joint filling mortar; 404, grout injection and drainage pipe; 501, upper precast concrete column; 502, lower precast Concrete column; 601, precast concrete column; 602, precast concrete beam; 603, post-cast concrete.

Detailed ways

In order to have a clearer understanding of the technical features, purposes and effects of the present invention, the specific implementation manners of the present invention will now be described in detail with reference to the accompanying drawings.

As shown in Figures 1-3, it is a grouting sleeve 100 for prefabricated concrete member steel bar connection of a preferred embodiment of the present invention, comprising seamless steel pipe 10, seamless steel pipe 10 is cut by long steel pipe, and seamless steel pipe 10 two The outer wall of the end side is provided with a grouting nozzle 12, the two ends of the seamless steel pipe 10 are used for inserting the connecting steel bar 200, and the high-strength non-shrinking grouting material 300 is poured into the gap in the grouting sleeve 100 from the grouting nozzle 12 . The inner wall of the seamless steel pipe 10 is provided with an internal thread 11, and both ends of the seamless steel pipe 10 are embedded with wedges 20. The sealing plug 50.

For further optimization, in this embodiment, the thickest end of the wedge body 20 is 5 mm away from the port of the seamless steel pipe 10 .

Further optimization, in the present embodiment, the wedge-shaped body 20 is processed by the numerical control machine tool, and the wedge-shaped body 20 is annular, and the outer diameter of the wedge-shaped body 20 is equal to the inner diameter of the seamless steel pipe 10, and the wedge-shaped body 20 is welded with the seamless steel pipe 10, and the wedge-shaped body The thickness of the thinnest end of the body 20 is 1mm-1.5mm.

Further optimization, in this embodiment, the grout injection and discharge nozzles 12 at both ends of the seamless steel pipe 10 are 10 to 15 mm away from the port, one end of the grout injection and discharge nozzle 12 communicates with the outside world, and the other end runs through the pipe wall sequentially along the radial direction of the seamless steel pipe 10 After connecting with the wedge body 20, it communicates with the inner cavity of the seamless steel pipe 10.

Further optimization, in this embodiment, the middle part of the seamless steel pipe 10 is provided with a limit pin 40 along the radial direction, and both ends of the limit pin 40 are welded to the inner wall of the seamless steel tube 10 . The limit pin 40 is used to limit the anchoring length of the connecting steel bar 200 .

Further optimization, in this embodiment, the internal thread 11 is distributed symmetrically with respect to the limit pin 40, the outer end of the internal thread 11 extends longest to the thinnest end of the wedge body 20, and the inner end of the internal thread 11 extends longest to close to the limit pin 40, and the distance from the limit pin 40 is 15mm.

For further optimization, the internal thread 11 is processed by a numerical control machine tool. In this embodiment, the pitch of the internal thread 11 is 2mm-4mm, and the thread depth is 1.5-3.5mm. The thickness of the material of the seamless steel pipe 10 is reduced by adopting a small pitch and a small thread depth, and the bonding between the high-strength non-shrink grouting material 300 and the grouting sleeve 100 is enhanced.

Further optimization, in this embodiment, the sealing plug 50 is made of rubber, the diameter of the opening in the middle is slightly smaller than the diameter of the connecting steel bar 200 , and the sealing plug 50 and the connecting steel bar 200 have an interference fit.

For further optimization, in this embodiment, the raw materials of the seamless steel pipe 10 and the wedge body 20 are common carbon steel or high-quality carbon structural steel or low-alloy high-strength steel that are easily available.

The present invention also proposes a preparation method of the grouting sleeve 100 for the connection of the above-mentioned prefabricated concrete member reinforcement, comprising the following steps:

The first step is to select a seamless steel pipe 10 with a suitable wall thickness and diameter according to the diameter of the connecting steel bar 200, and then cut a suitable length with an electric saw;

In the second step, the internal thread 11 of the seamless steel pipe 10 is turned by using a CNC machine tool, and the length of the thread is taken according to the actual design;

The third step is to select a seamless steel pipe 10 with a suitable wall thickness and an outer diameter equal to the inner diameter of the seamless steel pipe 10 and turn it into a wedge-shaped body 20 with a CNC machine tool;

The fourth step is to put the wedge-shaped body 20 into the two ends of the seamless steel pipe 10 that has been processed with the internal thread 11. The first 5mm, then the seamless steel pipe 10 and the wedge-shaped body 20 are welded together to form a weld 30;

The fifth step is to punch a hole in the middle of the seamless steel pipe 10, insert the stop pin 40, and then connect the two ends of the stop pin 40 with the seamless steel pipe 10 by spot welding;

The sixth step is to drill a hole at the two ends of the seamless steel pipe 10 at a distance of 10-15 mm from the port and weld the grout nozzle 12. The diameter of the hole is the same as that of the welded grout nozzle 12.

The grouting sleeve 100 for connecting steel bars of prefabricated concrete members proposed by the present invention is suitable for the following working conditions.

Working condition 1. Rebar connection between precast concrete shear walls, as shown in Figure 4-5:

(1) When prefabricating the upper prefabricated shear wall 401 in the prefabricated component processing plant, install the grouting sleeve 100 at the end of the connecting steel bar 200 at the bottom of the component according to the specified depth, and seal the port where the connecting steel bar 200 is inserted with the sealing plug 50, and grout The other end of the sleeve 100 is fixed to the mold of the prefabricated component, and then the concrete is poured, and after reaching the specified strength, the mold is demoulded for use.

(2) During on-site installation of prefabricated shear wall components, use a crane to lift the upper prefabricated shear wall 401, and align the sleeve mouth of the grouting sleeve 100 embedded in the upper prefabricated shear wall 401 at the same position and protrude The exposed end of the connected steel bar 200 is then slowly lowered until the prefabricated shear wall is installed in place.

(3) After the prefabricated components are rectified and temporarily fixed, seal the joints with grouting mortar 403, and then pressurize the high-strength grouting pipe 404 connected to the grouting nozzle 12 of the grouting sleeve 100 from the low position. Shrink the grouting material 300 until the grouting material is discharged from the full section of the joint and the grouting nozzle 12 at the high position of the grouting sleeve 100. After sealing, it is cured to the specified strength, that is, the vertical longitudinal reinforcement of the prefabricated shear wall is completed. connect.

Working condition 2. Rebar connection between precast concrete columns, as shown in Figure 6:

The steel bar connection method between the upper precast concrete column 501 and the lower precast concrete column 502 is the same as the steel bar connection method between the upper precast shear wall 401 and the lower precast shear wall 402 in the first working condition.

Working condition 3. Rebar connection between precast concrete beams and columns, as shown in Figure 7:

(1) Reserve a gap of a certain length at the connection between the precast concrete column 601 and the horizontal steel bar of the precast concrete beam 602, and insert the grouting sleeve 100 together with the port sealing plug 50 into the horizontal connecting steel bar at the end of the left precast concrete column 601 200, after the prefabricated concrete beam 602 is installed in place, the left end of the connected horizontal connecting steel bar 200 is aligned with the right end, and then the grouting sleeve 100 installed on the horizontal connecting steel bar 200 at the left end is Move to the right until the middle part of the grouting sleeve 100 is located in the middle of the ends of the two connecting steel bars 200, install the sealing plugs 50 on both sides of the grouting sleeve 100, and install the grouting and discharging grout for connecting the grouting nozzle 12 Tube 404.

(2) Pour the gap between the precast concrete column 601 and the precast concrete beam 602 to form the post-cast concrete 603 and maintain it; then pour the high-strength non-shrinkage grouting material 300 from the grout injection and discharge pipe 404 until the grout injection and discharge pipe 404 Plugging after removing the grouting material is to complete the butt connection of the horizontal connecting steel bars 200 between the precast concrete beam-column nodes.

Each embodiment in this specification is described in a progressive manner, each embodiment focuses on the difference from other embodiments, and the same and similar parts of each embodiment can be referred to each other.

Embodiments of the present invention have been described above in conjunction with the accompanying drawings, but the present invention is not limited to the above-mentioned specific implementations, and the above-mentioned specific implementations are only illustrative, rather than restrictive, and those of ordinary skill in the art will Under the enlightenment of the present invention, many forms can also be made without departing from the gist of the present invention and the protection scope of the claims, and these all belong to the protection of the present invention.

Claims (10)

1. A grouting sleeve for prefabricated concrete member reinforcing bar connection, comprising a seamless steel pipe, the two ends of the seamless steel pipe are provided with a grouting nozzle, and the two ends of the seamless steel pipe are used to insert the connecting reinforcement, It is characterized in that the inner wall of the seamless steel pipe is provided with internal threads, wedge-shaped bodies are embedded in both ports of the seamless steel pipe, the thick ends of the wedge-shaped bodies are close to the ports, and the two ports of the seamless steel pipe are provided with There is a sealing plug cooperating with the connecting reinforcement. 2 . The grouting sleeve for connecting prefabricated concrete members to reinforcing bars according to claim 1 , wherein the thickest end of the wedge is 5 mm away from the port of the seamless steel pipe. 3 . 3. The grouting sleeve for prefabricated concrete member reinforcement connection according to claim 1, characterized in that, the wedge-shaped body is annular, the outer diameter of the wedge-shaped body is equal to the inner diameter of the seamless steel pipe, and the wedge-shaped body The wedge-shaped body is welded with the seamless steel pipe, and the thickness of the thinnest end of the wedge-shaped body is 1 mm to 1.5 mm. 4. The grouting sleeve for connecting prefabricated concrete members according to claim 1, characterized in that the distance between the grout injection nozzles at both ends of the seamless steel pipe is 10-15mm from the ports, and one end of the grout injection nozzles is connected to the outside world. The other end passes through the pipe wall and the wedge-shaped body sequentially along the radial direction of the seamless steel pipe, and communicates with the inner cavity of the seamless steel pipe. 5. The grouting sleeve for prefabricated concrete member reinforcement connection according to claim 1, characterized in that, the middle part of the seamless steel pipe is provided with a limit pin along the radial direction, and both ends of the limit pin are aligned with the The inner wall of the seamless steel pipe is welded. 6. The grouting sleeve for precast concrete member reinforcement connection according to claim 5, characterized in that, the internal threads are distributed symmetrically with respect to the stop pin, and the outer ends of the internal threads extend longest to the wedge-shaped The thinnest end of the body, the inner end of the internal thread extends longest to 15mm from the limit pin. 7 . The grouting sleeve for connecting prefabricated concrete members to steel bars according to claim 1 , wherein the pitch of the internal thread is 2 mm to 4 mm, and the thread depth is 1.5 to 3.5 mm. 8 . The grouting sleeve for connecting prefabricated concrete members to reinforcing bars according to claim 1 , wherein the sealing plug is made of rubber, and the sealing plug is in interference fit with the connecting steel bar. 9. The grouting sleeve for connecting prefabricated concrete members according to claim 1, wherein the material of the seamless steel pipe and the wedge is ordinary carbon steel or high-quality carbon structural steel or low-alloy high-strength steel . 10. the preparation method of prefabricated concrete member steel bar connection grouting sleeve according to claim 1, is characterized in that, comprises the following steps: The first step is to select a seamless steel pipe with an appropriate wall thickness and diameter according to the diameter of the connecting steel bar, and then cut the appropriate length with an electric saw; In the second step, the internal thread of the seamless steel pipe is turned by using a CNC machine tool; The third step is to select a seamless steel pipe with a suitable wall thickness and an outer diameter equal to the inner diameter of the seamless steel pipe and turn it into a wedge-shaped body with a CNC machine tool; The fourth step is to put the wedge-shaped body into the two ends of the seamless steel pipe that has been processed with internal threads, and the side with thicker wall thickness is close to the end of the seamless steel pipe, and then weld the seamless steel pipe and the wedge-shaped body to form a welded joint. seam The fifth step is to drill a hole in the middle of the seamless steel pipe, insert a limit pin, and then spot weld the seamless steel pipe at both ends of the limit pin; The sixth step is to drill a hole at both ends of the seamless steel pipe and weld the grout nozzle.