A crack treatment device based on SMA tensioning and a method of using the same

Abstract

The application discloses a crack treatment device based on SMA tension and a use method thereof, and the crack treatment device comprises a crack limiting zone and a connecting ring, one of the connecting rings is arranged at each of two ends of the crack limiting zone in the length direction of the crack limiting zone, a connecting piece is arranged on the connecting ring, and the crack limiting zone is made of an iron-based memory alloy.The use method comprises the following steps: S1, calculating a cracking load of a concrete member; S2, determining a cross section of the crack limiting zone and a restoring load size; S3, determining a crack limiting zone installation position along a crack direction, and the two ends of the crack limiting zone are respectively arranged on the two sides of the crack in a crack riding mode; S4, performing slotting and drilling according to the determined crack limiting zone position; S5, installing the crack limiting zone according to the slotting position, fixing and connecting the crack limiting zone by using the connecting piece, and coating an epoxy resin adhesive on the surface of the crack limiting zone for solidification; and S6, energizing the crack limiting zone. The application has the effects of improving crack repair quality and preventing further cracking of the crack.

Description

TECHNICAL FIELD

[0001] The application relates to the technical field of crack repair, in particular to a crack treatment device based on SMA tensioning and a use method thereof. BACKGROUND

[0002] Traditional concrete will produce cracks after a long time of use or impact extrusion, the existence of the cracks will affect the strength of the concrete structure, cause certain safety hazards and affect the appearance of the concrete structure surface, and it is necessary to adopt a certain treatment to fill and repair the cracks.

[0003] Traditional concrete crack treatment methods include surface sealing, injection, pressure grouting and filling sealing. The surface sealing method uses the capillary action of the cracks to absorb low-viscosity and good-permeability repair glue; the injection method injects low-viscosity and high-strength crack repair glue into the crack cavity under certain pressure; the pressure grouting method pressurizes the grouting material into the crack cavity under high pressure for a certain period of time; and the filling sealing method chisels a U-shaped or V-shaped groove along the crack direction on the surface of the component, and then fills the crack with modified epoxy resin or elastic joint sealing material.

[0004] According to the related technology in the above, the inventor believes that the traditional crack treatment method can repair the cracks, but cannot limit the further development of the cracks, resulting in poor repair effect. SUMMARY

[0005] In order to limit the further cracking of the cracks and improve the repair effect of the cracks, the application provides a crack treatment device based on SMA tensioning and a use method thereof.

[0006] In a first aspect, the application provides a crack treatment device based on SMA tensioning, which adopts the following technical scheme:

[0007] The crack treatment device based on SMA tensioning comprises a plurality of crack limiting assemblies, each of the crack limiting assemblies comprises a crack limiting belt and a connecting ring, one connecting ring is arranged at each end of the crack limiting belt in the length direction, a connecting piece is arranged on the connecting ring, and the crack limiting belt is made of an iron-based memory alloy.

[0008] By adopting the above technical scheme, the two ends of the crack limiting belt are installed on the concrete on both sides of the crack by the connecting piece, the crack limiting belt is energized, the length of the crack limiting belt is shortened and has prestress, the crack limiting belt pulls the concrete structure on both sides of the crack, and the further expansion of the crack is reduced. Through the cooperation of the crack limiting assembly and the connecting piece, the crack repair quality is improved, and the further cracking of the crack is prevented.

[0009] Optionally, an epoxy resin protective layer is arranged on the surface of the crack limiting belt.

[0010] By adopting the technical scheme, the epoxy resin protective layer improves the structural strength of the crack limiting zone and reduces the possibility of rust caused by moisture on the surface of the crack limiting zone.

[0011] Optionally, the connecting piece comprises a high-strength bolt and a fastening nut, the high-strength bolt passes through the connecting ring, and the fastening nut is threadedly connected to the high-strength bolt and abuts against the top surface of the connecting ring.

[0012] By adopting the technical scheme, the high-strength bolt is connected to the concrete structure, and the fastening nut abuts against the connecting ring, thereby achieving positioning of the crack limiting zone.

[0013] Optionally, the high-strength bolt is hollow, the high-strength bolt is provided with a communication inclined hole, the communication inclined hole is in communication with the inner cavity of the high-strength bolt, a stay is arranged in the inner cavity of the high-strength bolt, the bottom end of the stay is connected with a connecting block, the edge of the connecting block is connected with a plurality of insertion strips in the circumferential direction, the plurality of insertion strips are arranged in one-to-one correspondence with the plurality of communication inclined holes, one end of the insertion strip is inserted into the communication inclined hole, an abutting ratchet is arranged on the inner wall of the high-strength connecting bolt along the length direction, the stay is connected with an abutting piece, the abutting piece is arranged obliquely downward, the abutting piece abuts between adjacent teeth of the abutting ratchet, and the abutting piece is made of an elastic material.

[0014] By adopting the technical scheme, after the high-strength bolt is installed in the slot hole, the insertion strip on the connecting block is pulled out of the communication inclined hole and inserted into the surrounding structure, thereby improving the connection strength of the high-strength bolt. The abutting piece abuts against the abutting ratchet, thereby achieving one-way positioning of the abutting piece.

[0015] In a second aspect, the application provides a use method of a crack treatment device based on SMA tensioning, which adopts the following technical scheme:

[0016] A use method of a crack treatment device based on SMA tensioning, comprising the following steps:

[0017] S1: calculating the cracking load of a concrete member according to a design specification;

[0018] S2: determining the cross section of the crack limiting zone and the restoring load size according to the cracking load of the concrete member;

[0019] S3: determining the installation position of the crack limiting zone along the crack direction according to the crack size and length, and respectively arranging the two ends of the crack limiting zone on the two sides of the crack;

[0020] S4: slotting and drilling according to the determined position of the crack limiting zone;

[0021] S5: installing the crack limiting strip according to the slotting position, fixing and connecting the two ends of the crack limiting strip using the connecting piece, and coating the surface of the crack limiting strip with epoxy resin adhesive for curing;

[0022] S6: energizing the crack limiting strip to generate prestress, and simultaneously pulling and fixing the structure at the two ends thereof.

[0023] Optionally, the method further comprises the following steps: cleaning the floating dust in the slot hole and the crack.

[0024] By using the above technical solution, the floating dust in the slot hole is cleaned, and the possibility of affecting the connection strength of the crack limiting strip by the floating dust is reduced.

[0025] Optionally, the method further comprises the following steps: the setting direction of the crack limiting strip is perpendicular to the direction of the crack, and the interval between adjacent crack limiting strips is greater than the width of the crack limiting strip.

[0026] By using the above technical solution, since the length of the crack limiting strip is perpendicular to the length direction of the crack, the crack limiting strip can directly pull the concrete on both sides of the crack, which helps to improve the anti-cracking effect of the crack limiting strip on the crack.

[0027] Optionally, the method further comprises the following steps: after the crack limiting strip is energized, the slotting position of the crack limiting strip is plugged and smoothed using epoxy resin adhesive, and after the epoxy resin adhesive is cured, the surface of the wall body is subjected to surface sealing treatment.

[0028] By using the above technical solution, the surface of the concrete is subjected to sealing treatment, and the crack limiting strip is protected, thereby reducing the possibility of moisture corrosion of the surface of the crack limiting strip.

[0029] In summary, the present application has at least one of the following beneficial technical effects:

[0030] 1. By the mutual cooperation of the crack limiting assembly and the connecting piece, the crack repair quality is improved, and the further cracking of the crack is prevented.

[0031] 2. The setting of the plug-in strip improves the connection strength of the high-strength bolt, and improves the connection strength of the high-strength bolt and the concrete structure.

[0032] 3. The surface of the concrete is subjected to sealing treatment, and the crack limiting strip is protected, thereby reducing the possibility of moisture corrosion of the surface of the crack limiting strip. BRIEF DESCRIPTION OF DRAWINGS

[0033] Figure 1 is a structure diagram of a crack treatment device based on SMA tensioning according to Embodiment 1 of the present application.

[0034] Figure 2is a partial sectional view for embodying a mounting position of the crack-limiting band in the embodiment of the present application.

[0035] Figure 3 is a structural schematic view of a crack treatment device based on SMA tensioning according to Embodiment 2 of the present application.

[0036] Figure 4 is a partial sectional view for embodying a connecting member in Embodiment 2 of the present application.

[0037] Figure 5 is a partial sectional view for embodying an internal structure of the high-strength bolt in Embodiment 2 of the present application.

[0038] BRIEF DESCRIPTION OF DRAWINGS 1, crack-limiting band; 2, connecting ring; 3, epoxy resin protective layer; 4, high-strength bolt; 41, communicating inclined hole; 5, tension bar; 6, connecting block; 7, insertion strip; 8, pull ring; 9, abutting piece; 10, abutting ratchet; 11, fastening nut; 12, closed treatment layer. DETAILED DESCRIPTION

[0039] The following will be described in detail in combination with the accompanying drawings. Figures 1-5 The present application will be described in further detail. The embodiment of the present application provides a crack treatment device based on SMA tensioning and a use method thereof, which has the effects of improving crack repair quality and preventing further cracking of cracks.

[0040] Embodiment 1

[0041] Referring to Figure 1 and Figure 2 A crack treatment device based on SMA tensioning includes a crack-limiting band 1 and a connecting ring 2, and the connecting ring 2 is provided at both ends of the crack-limiting band 1. The crack-limiting band 1 is made of an iron-based memory alloy, and the surface of the crack-limiting band 1 is provided with an epoxy resin protective layer 3, and the thickness of the epoxy resin protective layer 3 is not less than 5 mm. When the crack-limiting band 1 is connected, the connecting ring 2 at both ends of the crack-limiting band 1 is connected and bonded to the concrete structure by an epoxy resin adhesive.

[0042] Embodiment 2

[0043] Referring to Figures 3-5, the difference between embodiment 2 and embodiment 1 is that one connecting piece for connecting with concrete is arranged on each connecting ring 2, the connecting piece comprises a high-strength bolt 4 and a fastening nut 11. The high-strength bolt 4 passes through the connecting ring 2, the high-strength bolt 4 is hollowly arranged, and the fastening nut 11 is threadedly connected to the high-strength bolt 4 and is arranged in abutment with the top surface of the crack-limiting zone 1. A plurality of communicating inclined holes 41 are formed in the peripheral wall of the high-strength bolt 4 in a circumferential direction, and the plurality of communicating inclined holes 41 are arranged in communication with the inner cavity of the high-strength bolt 4. A tension strip 5 is arranged in the high-strength bolt 4 along the length direction of the high-strength bolt 4, the top end of the tension strip 5 extends out of the inner cavity of the high-strength bolt 4 and is connected with a pull ring 8, and the bottom end of the tension strip 5 is connected with a connecting block 6. A plurality of insertion strips 7 are fixedly connected to the connecting block 6 in a circumferential direction, the ends of the plurality of insertion strips 7 away from the connecting block 6 are inclinedly upwardly extended and are arranged in one-to-one correspondence with the plurality of communicating inclined holes 41, and the ends of the insertion strips 7 are inserted into the communicating inclined holes 41. An abutting ratchet tooth 10 is fixedly connected to the inner ring wall of the high-strength bolt 4 along the length direction of the high-strength bolt 4, and an abutting piece 9 is connected to the tension strip 5, the end of the abutting piece 9 away from the tension strip 5 is arranged in an inclined downward direction, and the abutting piece 9 is clamped between two adjacent teeth of the abutting ratchet tooth 10. The tension strip 5, the connecting block 6, the insertion strips 7, the connecting block 6 and the abutting piece 9 are made of elastic PVC material.

[0044] With reference to Figure 4 and Figure 5 When the crack-limiting zone 1 is connected with the concrete structure, a hole is drilled at a suitable position on the concrete structure and the dust in the hole is cleaned, a chemical agent is put into the hole, and the chemical agent is mixed from substances such as vertical vinyl, quartz particles and curing agent. The bottom end of the high-strength bolt 4 is inserted into the hole by screwing, the chemical agent in the hole is broken and naturally expands. The chemical agent is integrated with the concrete structure under the extrusion of the high-strength bolt 4, so as to achieve a high-strength anchoring effect. After the connection of the high-strength bolt 4 is completed, the tension strip 5 is pulled outwards through the pull ring 8, the insertion strips 7 pass out of the connecting inclined holes and are inserted into the chemical agent mixture, so as to further improve the connection strength of the high-strength bolt 4. The abutting piece 9 abuts against two adjacent teeth of the abutting ratchet tooth 10, so as to achieve one-way positioning of the tension strip 5 and reduce the possibility that the insertion strips 7 are retracted into the high-strength bolt 4.

[0045] With reference to Figure 1 and Figure 3A method for using a crack treatment device based on SMA tensioning, comprising the following steps: when repairing a crack, calculating the cracking load of the concrete member according to the Code for Design of Concrete Structures GB50010-2010. The cross-sectional area of the crack limiting zone 1 and the recovery load size are determined according to the cracking load. The cross section of the crack limiting zone 1 in the application can be designed into various shapes such as circular, square or oval according to needs. The tensile force calculation formula of the memory alloy is: F = n * S * sigma (n is the number of SMA crack limiting zone 1, S is the cross-sectional area of SMA crack limiting zone 1, and sigma is the recovery coefficient of iron-based memory alloy material deformation).

[0046] Referring to Figure 1 , Figure 2 and Figure 4 , according to the size and length of the crack, the position of the crack limiting zone 1 is determined along the direction of the crack, and the direction of the crack limiting zone 1 remains perpendicular to the direction of the crack. The interval between adjacent crack limiting zones 1 is at least the width of one crack limiting zone 1. According to the determined position of the crack limiting zone 1, grooving is performed, the grooving shape is correspondingly arranged with the shape of the crack limiting zone 1, and the floating dust in the crack and the crack limiting zone 1 is cleaned. First, the bottom surface of the crack limiting zone 1 is coated with epoxy resin adhesive, then the crack limiting zone 1 is placed in the grooving position of the crack limiting zone 1, and the connecting ring 2 at both ends is connected to the concrete structure. The grooving position of the crack limiting zone 1 is sealed and smoothed using epoxy resin adhesive and is allowed to solidify, ensuring that the thickness of the epoxy resin protective layer 3 on the surface of the crack limiting zone 1 is not less than 5mm, and a hole for energizing the crack limiting zone 1 is reserved on the epoxy resin protective layer 3.

[0047] Referring to Figure 1 and Figure 3 , after the connection of the crack limiting zone 1 is completed, the crack limiting zone 1 is energized to generate prestress, which helps to prevent the crack from further cracking by pulling the concrete structure on both sides of the crack. Since the iron-based memory alloy has a one-way memory effect, it can continuously pull the structure on both sides of the crack. Since the crack limiting zone 1 remains perpendicular to the direction of the crack, the prestress of the crack limiting zone 1 can be maximally applied to the concrete on both sides of the crack, reducing the possibility of further cracking of the crack. The surface of the concrete is closed treated, and the surface layer of the concrete is provided with a closed treatment layer 12, which protects the crack limiting zone 1 and prevents the crack limiting zone 1 from rusting due to moisture.

[0048] The implementation principle of the crack treatment device based on SMA tensioning and the method for using the same in the embodiment of the application is that the crack limiting zone 1 made of iron-based memory alloy is connected to the concrete structure on both sides of the crack, and the crack limiting zone 1 is energized, the length of the crack limiting zone 1 is shortened, and the concrete on both ends is continuously pulled, which prevents the crack from further cracking.

[0049] The above are all preferred embodiments of the present application, and do not limit the protection scope of the present application, so that: all equivalent changes made according to the structure, shape, principle of the present application should be covered in the protection scope of the present application.

Claims

1. A SMA tensioning based crack treatment device, characterized by: The application relates to a crack-limiting assembly, which comprises a crack-limiting band (1) and connecting rings (2) arranged at both ends of the crack-limiting band (1) in the length direction, connecting members arranged on the connecting rings (2), the crack-limiting band (1) being made of an iron-based memory alloy, the connecting members comprising high-strength bolts (4) and fastening nuts (11), the high-strength bolts (4) penetrating through the connecting rings (2), the fastening nuts (11) being screwed on the high-strength bolts (4) and abutting against the top surfaces of the connecting rings (2), the high-strength bolts (4) being hollow, the high-strength bolts (4) being provided with communicating inclined holes (41) which communicate with the inner cavities of the high-strength bolts (4), the inner cavities of the high-strength bolts (4) being provided with braces (5), the bottom ends of the braces (5) being connected with connecting blocks (6), the edges of the connecting blocks (6) being connected with a plurality of insertion strips (7) in the circumferential direction, the insertion strips (7) being arranged in one-to-one correspondence with the communicating inclined holes (41), one end of the insertion strip (7) being inserted into the connecting inclined hole, the inner walls of the high-strength connecting bolts being provided with abutting ratchets (10) in the length direction, the braces (5) being connected with abutting pieces (9), the abutting pieces (9) being arranged in an inclined downward manner, the abutting pieces (9) abutting between the adjacent teeth of the abutting ratchets (10), and the abutting pieces (9) being made of elastic materials.

2. A crack treatment device based on SMA tensioning according to claim 1, characterized in that: The surface of the crack-limiting band (1) is provided with an epoxy resin protective layer (3).

3. A method of use of a crack treatment device based on SMA tensioning according to claim 2, characterized in that: The application further comprises the following steps: S1: calculating the cracking load of the concrete member according to the design specification; S2: determining the cross section of the crack-limiting band (1) and the restoring load according to the cracking load of the concrete member; S3: determining the installation position of the crack-limiting band (1) according to the crack size and length and along the crack direction, and the two ends of the crack-limiting band (1) are arranged on the two sides of the crack in a riding seam manner; S4: slotting and drilling according to the determined position of the crack-limiting band (1); S5: installing the crack-limiting band (1) according to the slotting position, fixing and connecting the two ends of the crack-limiting band (1) by using the connecting members, and coating epoxy resin adhesive on the surface of the crack-limiting band (1) for curing; S6: energizing the crack-limiting band (1) to generate prestress, and simultaneously pulling and fixing the structure at the two ends of the crack-limiting band (1).

4. A method of use of a crack treatment device based on SMA tensioning according to claim 3, characterized in that: The application further comprises the following steps: Cleaning the floating dust in the cracks and the slot holes obtained in the step S4.

5. A method of using a crack treatment device based on SMA tensioning according to claim 3, characterized in that: The application further comprises the following steps: The setting direction of the crack-limiting band (1) is perpendicular to the direction of the crack, and the interval between the adjacent crack-limiting bands (1) is greater than the width of the crack-limiting band (1).

6. A method of using a SMA tension-based crack treatment device according to claim 3, characterized in that: The application further comprises the following steps: After the crack-limiting band (1) is energized, the slotting position of the crack-limiting band (1) is blocked and smoothed by using the epoxy resin adhesive, and after the epoxy resin adhesive is cured, the surface of the wall body is subjected to surface sealing treatment.

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