A prefabricated conical self-detecting grout density sleeve

Abstract

This invention provides an assembled conical self-detecting grout density sleeve, comprising a conical sleeve with a first port and a second port at its two ends. A grouting port and a grouting outlet are respectively located on the outer surface of the conical sleeve on one side of the first port and the second port. A plurality of micro-grooves are evenly distributed on the inner wall of the conical sleeve, and carbon fiber sensing wires are arranged within these micro-grooves. The ends of the carbon fiber sensing wires extend from the first port to the outer side of the conical sleeve. This invention has the following advantages: it determines the grout density by detecting the change in resistance before and after grouting through the pre-arranged carbon fiber sensing wires within the sleeve; furthermore, the double-gradient conical structure design of the grouting sleeve improves the strength requirements of the grouting sleeve connection, shortens the necessary anchoring length, and optimizes stress transmission with a smaller first taper and enhances the anchoring effect of the grouting material with a larger second taper.

Description

Technical Field

[0001] This utility model is an assembled conical self-detecting grout density sleeve, belonging to the field of steel bar connection in prefabricated assembled buildings. Background Technology

[0002] Building industrialization is the main development direction of my country's future construction industry. The development space of prefabricated assembled concrete structure buildings is very broad. The connection problem of steel bars in prefabricated components is one of the key technologies. Developing a more reasonable connection form while ensuring connection performance is of great significance to the promotion of building industrialization.

[0003] In the field of precast concrete structures, grouting sleeve connections have fewer restrictions and higher reliability, and can be widely used for connecting precast components in precast buildings. The grouting sleeve connection consists of a grouting sleeve, reinforcing bars at both ends to be connected, and non-shrink high-strength cement mortar (grouting material). The principle is as follows: non-shrink grouting material is poured into the grouting sleeve, filling the gap between the grouting sleeve and the reinforcing bar. After the non-shrink grouting material hardens, it tightly bonds with the reinforcing bar and the grouting sleeve, forming an anchoring connection, thus connecting the two reinforcing bars together.

[0004] In practical engineering, the grout density of sleeves has a significant impact on project quality. Studies have shown that tensile strength can only be achieved when the grout density is ≥90%, while insufficient density can easily lead to steel bar slippage and increased residual deformation. Inadequate grouting can cause uneven stress transmission, reduce structural strength, and may have serious consequences in prefabricated structures. However, current methods for inspecting sleeve grout density mainly employ non-destructive testing such as ultrasonic waves, impact echoes, and X-ray scanning. These methods all have certain limitations and are complex to operate, making direct on-site inspection difficult.

[0005] Therefore, there is a need to develop a sleeve that can self-detect grout density, so that the grout density can be quickly, conveniently and accurately detected on-site after grouting, thus meeting the needs of actual engineering projects. Utility Model Content

[0006] To address the shortcomings of existing technologies, the purpose of this utility model is to provide an assembled conical self-detecting grout density sleeve.

[0007] To achieve the above objectives, this utility model is implemented through the following technical solution:

[0008] A prefabricated conical self-detecting grout density sleeve includes a conical sleeve with a first port and a second port at its two ends. A grouting port and a grout outlet are respectively provided on the outer surface of the conical sleeve on one side of the first port and the second port. A plurality of micro grooves are evenly formed on the inner wall of the conical sleeve, and carbon fiber sensing wires are arranged in the micro grooves. The ends of the carbon fiber sensing wires extend from the first port to the outside of the conical sleeve. Both the first port and the second port are sealed with rubber sealing rings. A limiting baffle is provided inside the conical sleeve.

[0009] Furthermore, the micro-groove has a ring-shaped structure, and the inner wall of the micro-groove is coated with an insulating layer.

[0010] Furthermore, the insulating layer is either polyimide or epoxy resin.

[0011] Furthermore, the carbon fiber sensing filament is bonded and fixed to the microgroove using an adhesive.

[0012] Furthermore, the adhesive is a modified epoxy adhesive.

[0013] Furthermore, the limiting baffle includes a first positioning baffle and a second positioning baffle, which are respectively adapted to the first port and the second port.

[0014] Furthermore, the grouting port is vertically positioned on the outer surface of the conical sleeve near the first port, and the grout outlet is horizontally positioned on the outer surface of the conical sleeve near the second port.

[0015] Furthermore, the conical sleeve has a first conical space and a second conical space respectively provided on the side near the first port and the second port, and the taper of the first conical space is smaller than the taper of the second conical space.

[0016] The beneficial effects of this utility model are:

[0017] By utilizing the characteristics of high conductivity and significant resistance change of carbon fiber sensing wire, the resistance change of carbon fiber sensing wire before and after grouting can be recorded and detected to determine the grout density. This method is convenient and practical, and can quickly determine the grout density inside the conical sleeve.

[0018] By designing a rubber sealing ring, during grouting density testing of the conical sleeve, after inserting the reinforcing bar into the conical sleeve, the sealing ring can seal the gap between the sleeve and the reinforcing bar during the grouting process, after the reinforcing bar is inserted into the conical sleeve from the first and second ports. This prevents grout from seeping out from the ports, ensuring that the grout completely fills the internal space of the sleeve. Furthermore, the sealing ring can reduce moisture loss during the early hardening of the grout, preventing shrinkage cracking.

[0019] By designing a limiting baffle, the first positioning baffle and the second positioning baffle are staggered and set inside the conical sleeve. This arrangement can not only position the steel bar and ensure the insertion depth of the steel bar, but also not significantly affect the flow of the grout during grouting, thereby improving the flow rate and grouting efficiency of the grout. Furthermore, due to the small obstruction, voids or air bubbles are less likely to be generated during grouting, which can improve the density of the grout.

[0020] By setting the grout inlet and outlet vertically and horizontally on the outer surface of the conical sleeve, a three-dimensional path of "vertical feeding + horizontal venting" can be formed. During the filling process, the grout can rise naturally along the slope of the conical cavity, and the air bubbles are discharged to the horizontal outlet on the side of the sleeve with the flow of grout, reducing the problem of insufficient density caused by air bubble retention.

[0021] The tapered sleeve features a double-conical structure at both ends, with different tapers at each end. The smaller taper of the first conical space optimizes stress transfer, while the larger taper of the second conical space enhances the anchoring effect of the grout, facilitates grout flow and filling, and improves construction efficiency. Furthermore, this design of the tapered sleeve provides effective restraint to delay the development of radial splitting cracks, thereby effectively improving the bond performance between the reinforcing steel and the grout. Attached Figure Description

[0022] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0023] Figure 1 This is a schematic diagram of the overall structure of an assembled conical self-detecting grout density sleeve according to the present invention;

[0024] Figure 2 This is a longitudinal sectional view of the assembled conical self-detecting grout density sleeve of this utility model.

[0025] Figure 3This is a side view of the assembled conical self-detecting grout density sleeve of this utility model.

[0026] Figure 4 This is a side sectional view of the assembled conical self-detecting grout density sleeve of this utility model.

[0027] In the figure, 1 is a conical sleeve; 2 is a grouting port; 3 is a grout outlet; 4 is a carbon fiber sensing wire; 5 is a rubber sealing ring; 101 is a micro groove; 102 is a first positioning baffle; and 103 is a second positioning baffle. Detailed Implementation

[0028] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0029] Please see Figures 1-4 This utility model provides a technical solution for a prefabricated conical self-detecting grout density sleeve, including a conical sleeve 1. The small ends of the conical sleeve 1 have a diameter of 40mm, the large end of the conical sleeve 1 has a diameter of 80mm, and the length of the conical sleeve 1 is 275mm. The conical sleeve 1 is prefabricated into a conical body using hot forging (temperature 800-1600℃) or cold forging (temperature -60-60℃) processes to ensure the density of the cylinder body. In addition, the two ends of the sleeve prefabricated body need to be forged to ensure that the ultimate tensile strength of the grouting sleeve body is not less than 400MPa. The two ends of the conical sleeve 1 are respectively provided with a first port and a second port. The outer surface of the conical sleeve 1 is provided with a grouting port 2 and a grout outlet 3 respectively located on one side of the first port and the second port. The inner wall of the conical sleeve 1 is evenly spaced at 10mm intervals. The sleeve has several micro-grooves 101, and carbon fiber sensing wires 4 are arranged in the micro-grooves 101. The ends of the carbon fiber sensing wires 4 pass through the first port to the outside of the conical sleeve 1. The carbon fiber sensing wires 4 are arranged circumferentially every 10 mm along the axial direction of the sleeve 1 to form a 360° detection network that can accurately detect the grouting density of each part inside the sleeve. Both the first port and the second port are sealed with rubber sealing rings 5. During the grouting process, after the reinforcing bar is inserted into the conical sleeve 1 from the first port and the second port, the sealing rings 5 ​​can seal the gap between the sleeve 1 and the reinforcing bar, preventing the grout from seeping out from the port and ensuring that the grout completely fills the internal space of the sleeve 1. In addition, the sealing rings 5 ​​can reduce the loss of moisture during the early hardening of the grout and prevent shrinkage cracking. The conical sleeve 1 is provided with a limiting baffle.

[0030] See Figure 2 and Figure 4 The micro-groove 101 has a ring structure, and the inner wall of the micro-groove 101 is coated with an insulating layer to prevent the carbon fiber sensing filament 4 from short-circuiting when in contact with metal. The insulating layer is either polyimide or epoxy resin.

[0031] See Figure 2 and Figure 4 The carbon fiber sensing wire 4 is bonded and fixed to the micro-groove 101 by an adhesive compatible with the grouting material. As the core detection element for self-detection of grout density, the carbon fiber sensing wire 4 has the characteristics of good conductivity, obvious resistance change, and strong compatibility with cement-based grouting materials. The adhesive is a modified epoxy resin.

[0032] See Figures 2-4 The limiting baffle includes a first positioning baffle 102 and a second positioning baffle 103. The first positioning baffle 102 and the second positioning baffle 103 are respectively adapted to the first port and the second port. The first positioning baffle 102 and the second positioning baffle 103 are set in the shape of 90° fan-shaped plates and are staggered in position. This setting can not only play a positioning role, but also not significantly affect the flow of grout during grouting, thereby improving the flow rate and grouting efficiency of grout. In addition, due to the small obstruction, it is not easy to generate voids or air bubbles during grouting, which can improve the grouting density. The first positioning baffle 102 is set at a distance of 120mm from the first port and the second positioning baffle 103 is set at a distance of 110mm from the second port. This can ensure the insertion depth of the reinforcing bar, prevent the reinforcing bar from being over-inserted, ensure that the end of the reinforcing bar forms sufficient grouting space with the inside of the sleeve, and also help the user to quickly position the bar and reduce human error.

[0033] See Figure 1 and Figure 3 The grouting port 2 is vertically arranged on the outer surface of the conical sleeve 1 near the first port, and the grout outlet 3 is horizontally arranged on the outer surface of the conical sleeve 1 near the second port. Through the vertical and horizontal arrangement of the grouting port 2 and the grout outlet 3, a three-dimensional path of "vertical feeding + horizontal venting" can be formed. During the filling process, the grout can rise naturally along the slope of the conical inner cavity, and the air bubbles are discharged to the horizontal grout outlet on the side of the sleeve with the flow of grout, reducing the problem of insufficient density caused by air bubble retention.

[0034] See Figures 1-2The conical sleeve 1 has a first conical space and a second conical space respectively located on the side near the first port and the second port. The taper of the first conical space is smaller than that of the second conical space. The double-gradient conical structure of the conical sleeve 1 is conducive to the flow and filling of grout. The threaded pre-fixing reduces the positioning deviation of the reinforcing bars and improves the construction efficiency. In addition, the conical sleeve slope designed in this way can provide an effective constraint to delay the development of radial splitting cracks, thereby effectively improving the bonding performance between the reinforcing bars and the grout. Furthermore, the smaller taper of the first conical space can optimize stress transmission, and the larger taper of the second conical space can enhance the anchoring effect of the grout.

[0035] The circuits and electronic components, modules and controllers, or the heat dissipation holes and maintenance doors in the space of the adapted electrical equipment are all existing technologies, which can be fully implemented by those skilled in the art, and need not be elaborated. The content protected by this application does not involve improvements to software and methods or heat dissipation and maintenance.

[0036] The carbon fiber sensing wire 4 itself has good conductivity, and its resistance value will change with the changes in its own shape (such as strain, damage).

[0037] In use, the carbon fiber sensing wire 4 is arranged in the groove 101 on the inner wall of the conical sleeve 1. The end of the carbon fiber sensing wire 4 extends from the first port of the conical sleeve 1 and is externally connected to the resistance data collector through the extended sensing wire. Then, the grouting density can be judged by judging the change in resistance of the carbon fiber sensing wire 4 before and after grouting.

[0038] The specific process for determining the grout density is as follows:

[0039] An external resistance data collector is connected to the carbon fiber sensing wire 4 extending from the outside of the sleeve 1 via a wire. First, the resistance data of the carbon fiber sensing wire 4 is recorded before grouting. Then, the resistance data is recorded again after grouting, and the resistance change of the carbon fiber sensing wire is continuously observed. If the grouting is dense, the cement-based material will tightly wrap the carbon fiber sensing wire 4, forming a stable "fiber-matrix" interface. At this time, the resistance of the carbon fiber sensing wire 4 is less affected by environmental interference, stress transmission is uniform, carbon fiber strain is small and continuously distributed, and resistance changes are stable. If there are voids or loose areas, the carbon fiber sensing wire 4 may be exposed to air or poorly bonded to the matrix, leading to stress concentration or interruption of transmission, sudden changes in local carbon fiber strain, and abnormal resistance changes (such as abnormally high resistance values ​​or increased fluctuation amplitude). After the grouting density test is completed, if the grouting density meets the requirements, the portion of the carbon fiber sensing wire extending from the sleeve can be directly cut off for subsequent construction.

[0040] Although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole. The technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A prefabricated conical self-detecting grout density sleeve, characterized in that, The device includes a conical sleeve (1), with a first port and a second port at its two ends. A grouting port (2) and a grout outlet (3) are provided on the outer surface of the conical sleeve (1) on one side of the first port and the second port, respectively. A plurality of micro grooves (101) are evenly provided on the inner wall of the conical sleeve (1). Carbon fiber sensing wires (4) are arranged in the micro grooves (101). The end of the carbon fiber sensing wires (4) extends from the first port to the outside of the conical sleeve (1). Both the first port and the second port are sealed with rubber sealing rings (5). A limiting baffle is provided inside the conical sleeve (1).

2. The assembled conical self-detecting grout density sleeve according to claim 1, characterized in that, The micro-groove (101) has a ring structure, and the inner wall of the micro-groove (101) is coated with an insulating layer.

3. The assembled conical self-detecting grout density sleeve according to claim 2, characterized in that, The insulating layer is either polyimide or epoxy resin.

4. The assembled conical self-detecting grout density sleeve according to claim 3, characterized in that, The carbon fiber sensing filament (4) is glued and fixed to the microgroove (101) by an adhesive.

5. The assembled conical self-detecting grout density sleeve according to claim 4, characterized in that, The adhesive is a modified epoxy resin.

6. The assembled conical self-detecting grout density sleeve according to claim 5, characterized in that, The limiting baffle includes a first positioning baffle (102) and a second positioning baffle (103), which are respectively adapted to the first port and the second port.

7. The assembled conical self-detecting grout density sleeve according to claim 6, characterized in that, The grouting port (2) is vertically arranged on the outer surface of the conical sleeve (1) near the first port, and the grout outlet (3) is horizontally arranged on the outer surface of the conical sleeve (1) near the second port.

8. The assembled conical self-detecting grout density sleeve according to claim 7, characterized in that, The conical sleeve (1) has a first conical space and a second conical space on the side near the first port and the second port, respectively. The taper of the first conical space is smaller than the taper of the second conical space.

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