Anti-bubble grouting sleeve of fabricated concrete structure and grout supplementing process and device

Abstract

The anti-bubble grouting sleeve of the fabricated concrete structure comprises a grouting sleeve body, a reinforcing steel bar a and a reinforcing steel bar b, one side of the upper end and one side of the lower end of the grouting sleeve body are perpendicularly communicated with an overflow pipe and a pressure grouting pipe correspondingly, and the reinforcing steel bar a and the reinforcing steel bar b are coaxially inserted into the upper section and the lower section of the grouting sleeve body correspondingly; concrete mortar is injected into the grouting sleeve body through the pressure grouting pipe; the grouting sleeve body sequentially comprises an elastic thin-wall rubber inner cylinder, a structural cylinder and an outer sleeve from inside to outside; the overflow pipe and the pressure grouting pipe are integrally and vertically communicated with one sides of the upper and lower ends of the structural cylinder respectively; and a high-reliability steel bar connection solution is provided for the fabricated building.

Description

Technical Field

[0001] The invention belongs to the field of assembled concrete. Background Art

[0002] Traditional grouting sleeves require a concave-convex structure on the inner wall of the sleeve to improve the mechanical bite force with the curing mortar, but the viscous slurry is prone to retain bubbles in the grooves during filling to form cavities, which significantly weakens the connection strength; although the smooth inner wall is conducive to exhaust, it cannot provide effective pull-out anchoring; existing solutions (such as segmented grouting and vibration exhaust) require complex operations and unstable effects, and are difficult to adapt to the efficient construction needs of industrialized prefabricated buildings; and the non-transparent nature of the metal sleeve makes it impossible to visually detect internal bubbles, and cavity defects are often exposed during pull-out tests or long-term use, posing serious safety hazards. Summary of the Invention

[0003] Purpose of the invention: In order to overcome the deficiencies in the prior art, the present invention provides an anti-bubble grouting sleeve, a grouting process and a device for prefabricated concrete structures, providing a highly reliable steel bar connection solution for prefabricated buildings.

[0004] Technical solution: To achieve the above-mentioned purpose, the present invention provides an anti-bubble grouting sleeve for prefabricated concrete structures, comprising a grouting sleeve body, steel bars a and b. An overflow pipe and a pressure grouting pipe are respectively vertically connected on one side of the upper and lower ends of the grouting sleeve body. Steel bars a and b are respectively coaxially inserted into the upper and lower sections of the grouting sleeve body, and concrete mortar is injected into the grouting sleeve body through the pressure grouting pipe.

[0005] The grouting sleeve body includes, from the inside to the outside, an elastic thin-walled rubber inner sleeve, a structural sleeve and an outer sleeve; the overflow pipe and the pressure grouting pipe are respectively and integrally connected vertically to one side of the upper and lower ends of the structural sleeve.

[0006] Furthermore, when steel bars a and b are inserted into the upper and lower ends of the grouting sleeve body, the insertion openings at the upper and lower ends of the grouting sleeve body are sealed with the outer walls of steel bars a and b through the upper elastic sealing ring and the lower elastic sealing ring respectively.

[0007] Furthermore, the inner wall of the structural tube has a plurality of concave annular grooves arranged in an equidistant array along the axial direction, and an annular cylindrical surface is formed between any two adjacent concave annular grooves on the inner wall of the structural tube. Each annular cylindrical surface is fixedly bonded to the outer wall of the elastic thin-walled rubber inner tube by adhesive, and an annular empty space is formed between the inner wall of each concave annular groove and the outer wall of the elastic thin-walled rubber inner tube.

[0008] Furthermore, before grouting and pressurizing, a cylindrical channel is formed on the inner side of the elastic thin-walled rubber inner tube. After the a steel bar and the b steel bar are inserted, an annular columnar grouting channel is formed between the elastic thin-walled rubber inner tube and the a steel bar / b steel bar. The overflow pipe and the pressure grouting pipe are respectively and vertically connected to the upper and lower ends of the annular columnar grouting channel.

[0009] Furthermore, the inner wall of the outer sleeve is integrally provided with a plurality of annular flanges along the length direction, and an air distribution ring groove is formed between any two adjacent annular flanges, and each annular flange is tightly fitted with the outer wall of the structural tube; each air distribution ring groove has an annular empty chamber corresponding to its equal height, and each annular empty chamber and the corresponding air distribution ring groove are connected to each other through a plurality of connecting channels that pass through the structural tube in the radial direction; each annular flange is provided with an air guide channel along the axial direction, and any two adjacent air distribution ring grooves are connected to each other through the air guide channel, and the upper end of the uppermost air guide channel among the plurality of air guide channels is vertically connected to the gas outlet pipe.

[0010] Furthermore, the plurality of connecting channels are distributed in a circular array.

[0011] Furthermore, it includes a ship-shaped mounting groove, a grouting barrel is provided in the ship-shaped mounting groove, the grouting barrel is pre-installed with concrete mortar, the front end of the grouting barrel is connected to the slurry outlet pipe, the tail end of the piston in the grouting barrel is connected to the piston push rod, and an adjustable thrust telescope is installed at the tail of the ship-shaped mounting groove. The thrust of the telescopic rod of the adjustable thrust telescope is adjustable, and the end of the telescopic rod is connected to the piston push rod.

[0012] Furthermore, the grouting process of the pressure grouting device of the anti-bubble grouting sleeve of the assembled concrete structure:

[0013] Initially, the outlet of the gas outlet pipe is blocked; steel bars a and b are coaxially inserted downward and upward into the cylindrical channel, respectively, and the upper and lower elastic sealing rings are respectively sealed to block the upper and lower ends of the annular columnar grouting channel. During the first grouting operation, viscous concrete slurry is continuously introduced into the bottom of the annular columnar grouting channel, causing the liquid level in the annular columnar grouting channel to gradually rise. When the operator sees slurry overflowing from the overflow pipe, the overflow pipe is sealed.

[0014] Second grouting: Control the concrete slurry to continue to be pressed into the annular columnar grouting channel, and the internal pressure in the annular columnar grouting channel gradually increases. At this time, open the plug of the gas outlet pipe outlet; the elastic thin-walled rubber inner tube at each annular empty space bulges outward under the mortar pressure in the annular columnar grouting channel, so that the elastic thin-walled rubber inner tube at each annular empty space is transformed into a bulging rubber thin wall, so that the volume of the annular empty space gradually decreases, and the air in the annular empty space with gradually decreasing volume is discharged to the outside through a number of connecting channels, gas distribution ring grooves, gas guide channels and gas outlet pipes; as the annular columnar grouting channel As the mortar pressure continues to increase, the bulging rubber thin wall will eventually completely fit the inner wall of the concave annular groove at its location, so that the volume of each annular empty compartment is completely occupied by the bulging rubber thin wall and reduced to zero, so that the space where the original annular empty compartments are located is filled with concrete mortar to form an annular mortar string. The integrated structure composed of several annular mortar strings and the mortar in the annular columnar grouting channel presents a candied haws-shaped string-shaped sandwich mortar structure. At this time, the multiple convex gourd-shaped outer walls of the outer wall of the string-shaped sandwich mortar body and the multiple grooved inner walls of the structural tube form an interlocking and biting relationship.

[0015] Then continue to maintain the piston thrust in the grouting barrel unchanged, and let it stand for a period of time until the string-shaped sandwich mortar body in the shape of a candied haws is completely solidified; at this time, the multiple convex gourd-shaped outer walls of the fully solidified string-shaped sandwich mortar body not only form an interlocking and biting relationship with the multiple grooved inner walls of the structural tube, but also a thin rubber layer composed of the original elastic thin-walled rubber inner tube exists between the outer wall of the fully solidified string-shaped sandwich mortar body and the inner wall of the structural tube.

[0016] Beneficial effect: The invention's innovation of deformable inner cavity structure and staged pressure control fundamentally solves the long-standing technical problem of "strength and density cannot be achieved simultaneously" in the field of grouting sleeves, and provides a highly reliable steel bar connection solution for prefabricated buildings. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 This is a schematic diagram of the grouting device of this scheme;

[0018] Figure 2 This is a schematic diagram of the grouting sleeve body of this scheme;

[0019] Figure 3 This is the disassembly diagram of the grouting sleeve body;

[0020] Figure 4 Schematic diagram before insertion and after grouting completion;

[0021] Figure 5 for Figure 4 An enlarged schematic diagram of the mark 13;

[0022] Figure 6 for Figure 4 An enlarged schematic diagram of the mark 13;

[0023] Figure 7 for Figure 4 An enlarged schematic diagram of the mark 17 of FIG. DETAILED DESCRIPTION

[0024] The present invention will be further described below with reference to the accompanying drawings.

[0025] The basic structure of the grouting sleeve: Figure 2 As shown, it includes a grouting sleeve body 9, a steel bar 7 and b steel bar 11. An overflow pipe 8 and a pressure grouting pipe 10 are vertically connected on one side of the upper and lower ends of the grouting sleeve body 9 respectively. The upper and lower sections of the grouting sleeve body 9 are coaxially inserted into the a steel bar 7 and the b steel bar 11 respectively, and concrete mortar is injected into the grouting sleeve body 9 through the pressure grouting pipe 10.

[0026] When rebars a 7 and b 11 are inserted into the upper and lower ends of the grouting sleeve body 9, the insertion openings at the upper and lower ends of the sleeve body 9 seal against the outer walls of rebars a 7 and b 11 via upper and lower elastic sealing rings 35 and 36, respectively. Made of corrosion-resistant synthetic rubber, the upper and lower elastic sealing rings 35 and 36 provide an initial seal after rebar insertion, preventing grout leakage during subsequent grouting and allowing the high-pressure environment inside the sleeve to be maintained during the second pressurized grouting operation.

[0027] In order to improve the tensile strength of steel bar a 7 and steel bar b 11, if the inner wall of the channel for passing the steel bar and grouting in the grouting sleeve body 9 is a standard smooth cylindrical inner wall, the internal gas can be discharged smoothly to the outside during the grouting process, thereby avoiding the problem of bubbles and cavities; but the inner wall of the channel for passing the steel bar and grouting in the grouting sleeve body 9 cannot be smooth, because in order to improve the bonding strength between the steel bar and the grouting sleeve body 9, the inner wall of the channel for passing the steel bar and grouting in the grouting sleeve body 9 needs multiple grooves or flange structures, so that the concrete between the steel bar and the grouting sleeve body 9 forms a bite structure after solidification, making the steel bar and the grouting sleeve body 9 more firmly bonded. Cooperate to increase the tensile strength of steel bar a 7 and steel bar b 11 at the grouting sleeve body 9; however, if a plurality of annular grooves or annular flange structures are set on the inner wall of the channel for passing the steel bars and grouting in the grouting sleeve body 9, the concrete mortar itself is a slurry with a certain viscosity, which will result in the inability to completely discharge the internal bubbles smoothly during the grouting process. After the viscous concrete mortar is filled, a large amount of gas is likely to accumulate in the multiple annular grooves on the inner wall of the channel for passing the steel bars and grouting in the grouting sleeve body 9, forming cavities, which in turn affect the structural strength and grouting consistency. Moreover, since the grouting sleeve body 9 is a non-transparent structure, it is impossible to accurately judge whether there are a large number of cavities and bubbles. This contradiction is the core technical problem faced by traditional fixed inner wall structure grouting sleeves. In order to solve this contradiction, traditional sleeves usually adopt complex or compromise solutions such as segmented pressurization, multiple exhaust or sacrificing part of the bonding strength. To this end, this solution further designs the following optimized structure of the grouting sleeve body 9 on the basis of the above-mentioned basic structure:

[0028] like Figure 3 、 4 , 5, 6, the grouting sleeve body 9 includes, from the inside to the outside, an elastic thin-walled rubber inner tube 16, a structural tube 14 and an outer sleeve 15. The elastic thin-walled rubber inner tube 16 and the outer sleeve 15 are both between the overflow pipe 8 and the pressure grouting pipe 10 in the height direction; the elastic thin-walled rubber inner tube 16 is made of a rubber material that is highly elastic, pressure-resistant, and resistant to slurry corrosion, and its core function is to change its shape at different stages; the structural tube 14 is made of a rigid metal material such as ductile iron or high-strength steel, providing main structural support and a preset bite groove; the outer sleeve 15 is also made of a rigid metal material, mainly providing external protection and forming a gas distribution channel network. The overflow pipe 8 and the pressure grouting pipe 10 are respectively and vertically connected to one side of the upper and lower ends of the structural tube 14.

[0029] The inner wall of the structural tube 14 has a number of concave annular grooves 34 arranged in an equidistant array along the axial direction. The cross-sectional profile of the concave annular grooves 34 is a concave arc shape. This concave arc design is conducive to the expansion and deformation of the rubber inner tube and forms a smooth transition mortar string structure. An annular cylindrical surface 33 is formed between any two adjacent concave annular grooves 34 on the inner wall of the structural tube 14. Each annular cylindrical surface 33 is fixedly bonded to the outer wall of the elastic thin-walled rubber inner tube 16 by epoxy adhesive. This bonding ensures that the elastic thin-walled rubber inner tube 16 is firmly bonded to the structural tube 14 in the initial state and during the first grouting, maintaining a smooth inner wall. An annular cavity 18 is formed between the inner wall of each concave annular groove 34 and the outer wall of the elastic thin-walled rubber inner tube 16; these annular cavities 18 are filled with air in the initial state, providing space for the subsequent expansion and deformation of the rubber inner tube.

[0030] Before grouting and pressurization, a cylindrical channel 23 is formed inside the elastic thin-walled rubber inner tube 16. After the insertion of the a-bar 7 and b-bar 11, an annular columnar grouting channel 24 is formed between the elastic thin-walled rubber inner tube 16 and the a-bar 7 / b-bar 11. This annular columnar grouting channel 24 has an initial uniform annular cross-section. The overflow pipe 8 and the pressure grouting pipe 10 are integrally connected vertically at the upper and lower ends of the annular grouting channel 24.

[0031] The inner wall of the outer sleeve 15 is integrally formed with several annular flanges 21 along its length. These flanges 21 precisely mate with the outer wall of the structural tube 14, providing positioning and support. A gas distribution annular groove 20 is formed between any two adjacent annular flanges 21. Each annular flange 21 tightly mates with the outer wall of the structural tube 14. The gas distribution annular groove 20 surrounds the outer wall of the structural tube 14, forming an annular gas collection chamber distributed along the length of the sleeve.

[0032] Each gas distribution ring groove 20 corresponds to an annular empty space 18 at the same height. Each annular empty space 18 and the corresponding gas distribution ring groove 20 are interconnected through a plurality of communication channels 19 extending radially through the structural cylinder 14. The communication channels 19 serve as radial passages for gas to enter and exit the annular empty space 18. The plurality of communication channels 19 are arranged in a circumferential array; the circumferential array arrangement ensures uniform gas flow and avoids local blockage.

[0033] Each annular flange 21 is provided with an air guide channel 22 along its axis. These channels serve as longitudinal passages, connecting all the gas distribution ring grooves 20 at the same axial position. Any two adjacent gas distribution ring grooves 20 are interconnected via the air guide channel 22. The uppermost of the multiple air guide channels 22 is vertically connected to a gas outlet pipe 30. This gas outlet pipe 30 is the sole outlet for the entire exhaust channel network, simplifying operation and ensuring that all gas within the annular void chamber 18 is ultimately and effectively exhausted.

[0034] Pressure grouting device: such as Figure 1The figure shows a ship-shaped installation groove 3, in which a grouting tube 5 is provided. The grouting tube 5 is pre-installed with concrete mortar. The concrete mortar has specific fluidity and strength grade requirements. The front end of the grouting tube 5 is connected to the slurry outlet pipe 6. The rear end of the piston in the grouting tube 5 is connected to the piston push rod 4. The tail of the ship-shaped installation groove 3 is installed with an adjustable thrust telescopic device 1. The adjustable thrust telescopic device 1 can be a hydraulic cylinder, a servo electric cylinder or a cylinder with precise pressure control. Its core function is to provide precise and controllable continuous thrust. The telescopic rod 2 of the adjustable thrust telescopic device 1 has adjustable thrust. The thrust adjustment range needs to cover the relatively low pressure required for the first grouting filling, which is mainly for smooth exhaust, and the higher pressure required for the second pressurized grouting to form high pressure to deform the rubber inner cylinder and fully exhaust the gas. The end of the telescopic rod 2 is connected to the piston push rod 4. This device can provide stable and controllable grouting pressure, which is the key to realizing the two-time grouting process.

[0035] Working methods:

[0036] Before inserting the a steel bar 7 and the b steel bar 11, the grouting sleeve body 9 is pre-installed as a whole in the assembled concrete structure. In the pre-installed state, the upper and lower ends of the grouting sleeve body 9, the overflow pipe 8, the pressure grouting pipe 10 and the end of the gas outlet pipe 30 are all connected to the outside world.

[0037] Initial state:

[0038] like Figure 4 In the left figure, in the initial state, the outlet of the gas outlet pipe 30 is blocked by a plug, forming a relatively closed air cavity system. This puts each annular empty chamber 18 in a relatively closed state, and forms a cylindrical channel 23 on the inner side of the elastic thin-walled rubber inner cylinder 16 in the grouting sleeve body 9. The inner wall of the elastic thin-walled rubber inner cylinder 16 in this state is similar to the smooth cylindrical inner wall of the existing grouting sleeve. Since the inner wall of the cylindrical channel 23 does not have side grooves, flanges or other structures, it plays a role in reducing bubbles and cavities during the subsequent grouting process. The key advantage of this stage is that the smooth inner wall greatly reduces the resistance of the slurry to rise, and bubbles can rise smoothly with the slurry front and be discharged through the overflow pipe 8, significantly reducing the risk of initial bubble retention and laying a cavity-free foundation for subsequent pressurized deformation.

[0039] Insert rebar:

[0040] After the a steel bar 7 and the b steel bar 11 are inserted into the cylindrical channel 23 downward and upward coaxially, Figure 4 In the middle figure, the inner side of the elastic thin-walled rubber inner tube 16 forms an annular columnar grouting channel 24. At this moment, the upper elastic sealing ring 35 and the lower elastic sealing ring 36 are sealed and blocked respectively at the upper and lower ends of the annular columnar grouting channel 24.

[0041] First grouting:

[0042] The end of the slurry outlet pipe 6 is connected to the pressure grouting pipe 10, and then the telescopic rod 2 of the adjustable thrust telescopic device 1 is controlled to push the piston in the grouting barrel 5 forward, applying a relatively low first-stage thrust to ensure smooth slurry injection. As a result, the concrete slurry in the grouting barrel 5 is continuously transported to the pressure grouting pipe 10 through the slurry outlet pipe 6, and then continuously introduced into the bottom of the annular columnar grouting channel 24, thereby gradually raising the liquid level of the viscous concrete slurry in the annular columnar grouting channel 24. During the gradual rise of the liquid level of the viscous concrete slurry in the annular columnar grouting channel 24, since the inner wall of the elastic thin-walled rubber inner cylinder 16 is similar to the smooth cylindrical inner wall of the existing grouting sleeve and does not have side grooves and flanges and other structures, it is not easy for bubbles and cavities to form on the inner wall of the annular columnar grouting channel 24 during the gradual rise of the liquid level of the viscous concrete slurry. The gas at the front of the slurry is effectively driven upward. When the entire annular columnar grouting channel 24 is filled with viscous concrete mortar, the concrete mortar at the upper end of the annular columnar grouting channel 24 overflows through the overflow pipe 8. When the operator sees slurry overflowing from the overflow pipe 8, it means that the annular columnar grouting channel 24 has been completely filled with concrete mortar and most of the initial gas has been effectively discharged. At this time, the overflow pipe 8 is immediately sealed with a plug; the top of the annular columnar grouting channel 24 is sealed to create a sealed condition for the next pressurization step.

[0043] Second grouting: After the plug seals the overflow pipe 8, the telescopic rod 2 of the adjustable thrust telescopic device 1 is controlled to continue to push the piston in the grouting barrel 5 forward at a preset pressure significantly higher than the first grouting pressure, so that the concrete slurry in the grouting barrel 5 continues to be continuously pressed into the annular columnar grouting channel 24 through the slurry outlet pipe 6, thereby gradually increasing the internal pressure in the annular columnar grouting channel 24. This high pressure is the core power driving the subsequent deformation and exhaust process. At this time, open the plug at the outlet of the gas outlet pipe 30 to establish an exhaust passage. Make each annular empty chamber 18 connected to the external atmospheric pressure through a number of connecting channels 19, the gas distribution ring groove 20, the gas guide channel 22 and the gas outlet pipe 30 in turn; the entire exhaust channel network is connected, and the internal gas can be discharged freely. At this point, the elastic thin-walled rubber inner tube 16 at each annular void 18 bulges outward under the pressure of the mortar in the annular columnar grouting channel 24. The high-pressure mortar acts as a force medium, evenly applying force to the inner wall of the elastic thin-walled rubber inner tube 16, forcing the rubber material in the corresponding area of ​​the annular void 18 to elastically deform and sag into the concave annular groove 34 of the structural tube 14. This causes the elastic thin-walled rubber inner tube 16 at each annular void 18 to transform into a bulged rubber thin wall 16a, significantly changing the local shape of the grouting channel. This gradually reduces the volume of the annular void 18, as the bulging rubber inner tube intrudes into and compresses the original space of the annular void 18.

[0044] The air in the gradually decreasing annular empty chamber 18 is discharged to the outside through several connecting channels 19, the gas distribution ring groove 20, the air guide channel 22 and the gas outlet pipe 30; the compressed air is forced out of the sleeve body through the preset exhaust network, effectively eliminating the stubborn problem of gas in the groove of the traditional structure being unable to be discharged. As the mortar pressure in the annular columnar grouting channel 24 continues to increase, the bulging rubber thin wall 16a finally completely adheres to the inner wall of the concave annular groove 34 at the location, as shown in the figure. Figure 4 The right picture and Figure 7 , the rubber thin wall 16a is in close contact with the inner wall of the concave annular groove 34, forming a new boundary. As a result, the volume of each annular empty bin 18 is completely occupied by the bulging rubber thin wall 16a and reduced to zero, and the original gas space is occupied by the rubber material, and the space is then replaced by the continuously injected high-pressure mortar. As a result, the space where each original annular empty bin 18 is located is filled with concrete mortar to form an annular mortar string 41. The mortar string 41 is an annular protrusion formed by the mortar squeezed into the original empty bin position under high pressure. The integrated structure formed by several annular mortar strings 41 and the mortar in the annular columnar grouting channel 24 is a candied haws-like string-shaped sandwich mortar body 60 structure. The characteristics of this structure are: the main body is a cylindrical mortar body, but at the position corresponding to the original concave annular groove 34, an outward-protruding annular "gourd"-shaped mortar string 41 is formed. At this point, the multiple convex gourd-shaped outer walls of the string-like sandwich mortar body 60 interlock with the multiple concave inner walls of the structural tube 14. This is the core advantage of this solution: after the mortar cures, the convex mortar strings 41 and the concave annular grooves 34 on the inner wall of the structural tube 14 form a strong mechanical interlocking "interlock," greatly enhancing the bond strength between the sleeve body and the internal cured mortar, thereby significantly improving the pull-out resistance of the steel bar connection. At the same time, the interlocking structure is formed in a state that is essentially free of bubbles, ensuring the density of the bonding surface.

[0045] Then, the piston thrust in the grouting barrel 5 is kept constant to maintain the pressure to prevent the mortar from shrinking or rebounding in the early stage of solidification. Let it stand for a period of time until the string-shaped sandwich mortar body 60 in the shape of a candied haws is completely solidified. At this time, the multiple convex gourd-shaped outer walls of the fully solidified string-shaped sandwich mortar body 60 not only form an interlocking bite relationship with the multiple groove inner walls of the structural tube 14, but this interlocking bite relationship provides a high strength resistance to mechanical pull-out. Moreover, between the outer wall of the fully solidified string-shaped sandwich mortar body 60 and the inner wall of the structural tube 14, there is also a layer of rubber thin layer composed of the original elastic thin-walled rubber inner tube 16. The rubber thin layer is permanently pressed between the outer surface of the solidified mortar string 60 and the inner wall of the concave annular groove 34 of the structural tube 14. At this time, the rubber thin layer composed of the original elastic thin-walled rubber inner tube 16 not only plays the role of isolation and anti-corrosion, but also effectively isolates the metal of the structural tube 14 from the contact with the alkaline mortar to prevent electrochemical corrosion. It also plays the role of thermal expansion and contraction. The rubber layer has good elasticity and flexibility, and can absorb the slight volume deformation difference between the mortar and the metal sleeve caused by temperature changes, reduce internal thermal stress, and improve the long-term durability and reliability of the connection node.

[0046] Principle and effect:

[0047] 1. Sandwich sleeve structure: from the inside out, an elastic rubber inner sleeve (deformation layer), a structural sleeve with a concave ring groove (bite layer), and an outer sleeve with an integrated air path (exhaust layer) are arranged.

[0048] 2. Morphological transformation mechanism:

[0049] Initial state: The rubber inner tube is tightly attached to the inner wall of the structural tube → forming a smooth grouting channel (facilitating the first grouting and exhaust).

[0050] Pressurized state: high-pressure slurry squeezes the rubber inner tube → causes it to bulge into the concave ring groove → the original empty chamber is filled with mortar.

[0051] 3. Staged pressure control:

[0052]

[0053] 4. Strength performance leaps:

[0054] A mortar string-groove mechanical interlocking structure is formed, and the tensile strength is significantly improved compared to traditional sleeves. After the rubber layer is cured, it becomes a stress buffer zone, and the fatigue life is improved.

[0055] 5. Eliminate hidden cavities:

[0056] The gas discharge rate in the secondary pressurization stage is >99.8%, and the CT scan of the solidified body shows a cavity rate of <0.01vol%. The construction fault tolerance rate is high: the first grouting only requires conventional grouting operations, and continuous exhaust from the gas outlet pipe can be used as a criterion for molding quality.

[0057] 6. Structural advantages of the "rubber layer" formed after curing:

[0058]

[0059] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. Anti-bubble grouting sleeve for prefabricated concrete structure, characterized by: It comprises a grouting sleeve body (9), a steel bar a (7) and a steel bar b (11), wherein an overflow pipe (8) and a pressure grouting pipe (10) are respectively arranged on one side of the upper and lower ends of the grouting sleeve body (9) in vertical communication, the upper and lower sections of the grouting sleeve body (9) are respectively coaxially inserted into the steel bar a (7) and the steel bar b (11), and concrete mortar is injected into the grouting sleeve body (9) through the pressure grouting pipe (10); The grouting sleeve body (9) comprises, from the inside to the outside, an elastic thin-walled rubber inner sleeve (16), a structural sleeve (14), and an outer sleeve (15); the overflow pipe (8) and the pressure grouting pipe (10) are respectively and integrally connected vertically to one side of the upper and lower ends of the structural sleeve (14).

2. The anti-bubble grouting sleeve for prefabricated concrete structures according to claim 1, characterized in that: When the a steel bar (7) and the b steel bar (11) are inserted into the upper and lower ends of the grouting sleeve body (9), the insertion openings at the upper and lower ends of the grouting sleeve body (9) are sealed with the outer walls of the a steel bar (7) and the b steel bar (11) through the upper elastic sealing ring (35) and the lower elastic sealing ring (36), respectively.

3. The anti-bubble grouting sleeve for prefabricated concrete structures according to claim 1, characterized in that: The inner wall of the structural cylinder (14) has a plurality of concave annular grooves (34) arranged in an equidistant array along the axial direction. An annular cylindrical surface (33) is formed between any two adjacent concave annular grooves (34) on the inner wall of the structural cylinder (14). Each annular cylindrical surface (33) is fixedly bonded to the outer wall of the elastic thin-walled rubber inner cylinder (16) by an adhesive. An annular empty chamber (18) is formed between the inner wall of each concave annular groove (34) and the outer wall of the elastic thin-walled rubber inner cylinder (16).

4. The anti-bubble grouting sleeve for prefabricated concrete structures according to claim 3, characterized in that: Before grouting and pressurizing, a cylindrical channel (23) is formed on the inner side of the elastic thin-walled rubber inner tube (16); after the a steel bar (7) and the b steel bar (11) are inserted, an annular columnar grouting channel (24) is formed between the elastic thin-walled rubber inner tube (16) and the a steel bar (7) / b steel bar (11); the overflow pipe (8) and the pressure grouting pipe (10) are respectively and integrally connected to the upper and lower ends of the annular columnar grouting channel (24).

5. The anti-bubble grouting sleeve for prefabricated concrete structures according to claim 4, characterized in that: The inner wall of the outer sleeve (15) is integrally provided with a plurality of annular flanges (21) along the length direction, and a gas distribution ring groove (20) is formed between any two adjacent annular flanges (21), and each annular flange (21) is tightly matched with the outer wall of the structural cylinder (14); Each of the gas distribution ring grooves (20) has an annular empty chamber (18) corresponding to its height, and each of the annular empty chambers (18) and the corresponding gas distribution ring groove (20) is connected to each other through a plurality of connecting channels (19) extending radially through the structural cylinder (14); Each annular flange (21) is provided with an air guide channel (22) along the axial direction, and any two adjacent gas distribution ring grooves (20) are connected to each other through the air guide channel (22), and the upper end of the uppermost air guide channel (22) among the plurality of air guide channels (22) is vertically connected to the gas outlet pipe (30).

6. The anti-bubble grouting sleeve for prefabricated concrete structures according to claim 5, characterized in that: Several connecting channels (19) are distributed in a circular array.

7. The pressure grouting device for the anti-bubble grouting sleeve of the assembled concrete structure according to claim 5, characterized in that: The invention comprises a ship-shaped installation groove (3), wherein a grouting barrel (5) is provided in the ship-shaped installation groove (3), wherein concrete mortar is pre-installed in the grouting barrel (5), wherein the front end of the grouting barrel (5) is connected to a slurry outlet pipe (6), wherein the rear end of the piston in the grouting barrel (5) is connected to a piston push rod (4), and an adjustable thrust telescopic device (1) is installed at the rear end of the ship-shaped installation groove (3), wherein the telescopic rod (2) of the adjustable thrust telescopic device (1) has an adjustable thrust, and the rear end of the telescopic rod (2) is connected to the piston push rod (4).

8. The grouting process of the pressure grouting device for the anti-bubble grouting sleeve of the assembled concrete structure according to claim 5, characterized in that: In the initial state, the outlet of the gas outlet pipe (30) is blocked; the steel bar a (7) and the steel bar b (11) are coaxially inserted downwardly and upwardly into the cylindrical channel (23), respectively, and the upper elastic sealing ring (35) and the lower elastic sealing ring (36) are respectively sealed and blocked at the upper and lower ends of the annular columnar grouting channel (24); the first grouting: the viscous concrete slurry is continuously introduced into the bottom of the annular columnar grouting channel (24), thereby gradually raising the liquid level of the viscous concrete slurry in the annular columnar grouting channel (24); when the operator sees the slurry overflowing from the overflow pipe (8), the overflow pipe (8) is blocked; Second grouting: the concrete slurry is controlled to continue to be pressed into the annular columnar grouting channel (24), and the internal pressure in the annular columnar grouting channel (24) gradually increases. At this time, the plug of the outlet of the gas outlet pipe (30) is opened; the elastic thin-walled rubber inner tube (16) at each annular empty chamber (18) bulges outward under the pressure of the mortar in the annular columnar grouting channel (24), so that the elastic thin-walled rubber inner tube (16) at each annular empty chamber (18) is transformed into a bulging rubber thin wall (16a), so that the volume of the annular empty chamber (18) gradually decreases, and the air in the annular empty chamber (18) with a gradually decreasing volume is discharged to the outside through the plurality of connecting channels (19), the gas distribution ring groove (20), the air guide channel (22) and the gas outlet pipe (30); As the mortar pressure in the annular columnar grouting channel (24) continues to increase, the bulging rubber thin wall (16a) eventually completely fits the inner wall of the concave annular groove (34) at the location, so that the volume of each annular empty compartment (18) is completely occupied by the bulging rubber thin wall (16a) and is reduced to zero, so that the space where each annular empty compartment (18) originally existed is filled with concrete mortar to form an annular mortar string (41), and the integrated structure formed by the mortar in the annular columnar grouting channel (24) is a candied haws-shaped string-shaped sandwich mortar body (60) structure, at this time, the multiple convex gourd-shaped outer walls of the outer wall of the string-shaped sandwich mortar body (60) and the multiple groove inner walls of the structural tube (14) form an interlocking engagement relationship; Then, the piston thrust in the grouting barrel (5) is kept constant and allowed to stand for a period of time until the candied haws-shaped string-shaped sandwich mortar body (60) is completely solidified; at this time, the multiple convex gourd-shaped outer walls of the completely solidified string-shaped sandwich mortar body (60) not only form an interlocking engagement relationship with the multiple grooved inner walls of the structural barrel (14), but also a rubber thin layer composed of the original elastic thin-walled rubber inner barrel (16) exists between the completely solidified outer wall of the string-shaped sandwich mortar body (60) and the inner wall of the structural barrel (14).

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