KR20230007685A - Ahchoring device using shape memory alloy for compression-type fixing sleeve and frp tendon ahchoring method using the same - Google Patents

Abstract

In fixing an FRP tension member to a structure using a compression type fixing device, disclosed are a shape memory alloy compression anchorage and an FRP tension member anchorage method using the same. Since a shape memory alloy compression anchorage uses a shape memory alloy anchorage, it is more effective in securing the compression force of FRP tension members which are vulnerable to shear stress, and it is possible to fix by heating, so that the fixing space can be used efficiently, so it has excellent usability and economy. To this end, the shape memory alloy compression anchorage comprises a fixing block, a fixing hole, and an inner protrusion.

Description

Shape-memory alloy compression anchorage and FRP tension member anchorage method using the same

The present invention relates to a shape memory alloy crimping anchorage. More specifically, in fixing the FRP tension member to a structure using a compression type anchorage device, using a shape memory alloy anchorage device is more effective in securing the compression force of the FRP tension member, which is vulnerable to shear stress, while fixing by heating is possible, resulting in a settlement space It relates to a shape-memory alloy compression anchorage with excellent usability and economy because it can efficiently use it, and a FRP tension member anchorage method using the same.

Figure 1a shows a stress-strain graph of a conventional shape memory alloy (Shape Memory Alloy, SMA).

Shape memory, a characteristic of Shape Memory Alloy (SMA), is that a shape memory alloy deformed at a low temperature maintains its deformed shape until heat is applied, but returns to its original shape when the temperature rises with heat applied. it means.

These shape memory characteristics are known to be the result of changes in the state of solids induced by temperature or stress.

Accordingly, it is known that the shape memory alloy has martensite and austenite states as shown in FIG. 1a, and these depend on heat treatment in the manufacturing process.

At this time, in the austenite state, when the load is removed after deformation by a load, the deformation is automatically restored to the original state.

However, in the martensitic state, when the load is removed, some of the strain is recovered, and a large amount of strain is not recovered and remains as residual strain. However, if the temperature is increased by heating, the deformation is restored to its original state. When the shape memory alloy in the martensitic state is heated and the temperature is increased while the deformation is restrained, stress is generated inside the alloy, which causes other objects to used to restrain

Figure 1b is examples of applications to concrete structures or other devices using these conventional shape memory alloys (Shape Memory Alloy, SMA).

First of all, in the case of a column structure, which is a concrete structure, in the case of using an austenite shape memory alloy, deformation can be restored to its original shape without a heating means, so it can be effectively used to restrain other objects by restraining this deformation recovery. Although,

At the time of initial installation, if it is necessary to be installed on a column structure while securing adhesion so that it can be integrated with the column structure (31), a shape memory alloy (SMA) is manufactured in a martensite state and the column is heated during the heating process. The column structure is constrained while securing the adhesion with the structure.

Therefore, in the case of Figure 1b, it can be seen that the shape memory alloy (SMA, 10) and the shape memory alloy (SMA, 20) in the form of a plate can be used, and further, the shape memory alloy (SMA) and It can be seen that it can also be applied to the damping device 32 and the bridge support 33 using the wire-shaped shape memory alloy (SMA) properties.

Figure 1c shows an example of applying a shape memory alloy (Shape Memory Alloy, SMA) to a tool holder for fixing a conventional tool.

That is, the tool mounting portion 11 formed through the tool fixing hole 12 having a relatively smaller inner diameter than the outer diameter of the shank portion S of the tool;

At least one shape memory alloy ring 15 inserted into the ring fixing hole formed in the tool mounting portion to have a relatively larger inner diameter than the tool fixing hole; and

By the deformation of the shape memory alloy ring 15 by the heating source and the cooling source provided to the shape memory alloy ring 15, the inner diameter size of the tool fixing hole 12 is forcibly changed to clamp or unscrew the tool. It can be seen that clamping is possible.

However, this shape memory alloy ring 15 is formed in a form for simply clamping the shank portion (S) of the tool rather than a fixing action under tensile stress like an FRP tension member, so that the tensile stress caused by tension is continuously There is a limit to using FRP tension members for anchorage.

Figure 1d is an exemplary view of a fixing device 60 using a conventional shape memory alloy.

That is, both anchoring plates 62 that are fixedly installed on the PSC structure 61 and transmit the introduced tension force; a tension member 63 installed between the two fixing plates 62; A horizontal fixture 64 formed at one end of the tension member 63 and supported by the anchoring plate 62 to fix the tension member; When the tension member 63 is re-tensioned, the reaction plate 65 fixed to the PSC structure 61 without being changed in position; And a block of shape memory alloy (SMA) material integrated between the horizontal anchoring device 64 integrated with the tension member 63 and the reaction plate 65 in which contraction is restrained, so that the tension member 63 is re-tensioned by applying electricity. and an end anchoring block 66 in which contraction occurs in the direction of the end anchoring block 66, and one end of the end anchoring block 66 includes a socket fastening method to be integrated with the horizontal anchoring hole 64 while accommodating the pulled tension member. It is formed to be integrated with the horizontal anchoring hole 64, and the other side of the end anchoring block 66 is installed in such a way as to be integrated with the reaction plate 65 so that it can be detached and adjusted so that the amount of shrinkage can be adjusted while adjusting the required installation size will be.

At this time, the end anchoring block 65 is a block made of a shape memory alloy (SMA) that contracts in the re-tension direction of the tension member 63, and is installed between the horizontal anchoring device 64 and the reaction force plate 65 in a socket fastening method, It can be seen that it is not intended to fix the tension member 63 itself.

1e is a view showing ductility characteristics in a conventional reinforcement method of reinforced concrete structures and an exemplary view of forming a compression type sleeve.

Ductility is expressed as the ratio of strain from the yield of reinforcing bars to just before fracture. Rebars behave ductile, and FRP tension members (FRP reinforcements, FRP) behave brittle. When such ductility is insufficient, reinforced concrete structures It can be a brittle structure.

Therefore, since the ductility of reinforced concrete structures can be reduced when reinforced with FRP tension members, there are ways to arbitrarily form unattached sections to secure ductility. There was a problem with dropping it.

Accordingly, among the methods of fixing the FRP tension member, the compression-type fixing device is particularly used because it has advantages such as reducing the fixing length and securing the safety of the fixing device.

This compression-type fixing device is a device that compresses the compression sleeve 52 on the outer circumferential surface of the FRP tension member and fixes the compression sleeve 52 compressed to the FRP tension member after tension using a separate fixing device.

Accordingly, according to FIG. 1d, it can be seen that swaging equipment is used to compress the compression sleeve 52 to the FRP tension member.

That is, the compression sleeve 52 is inserted into the FRP tension member 51 to align it between the hydraulic jack 52 for extrusion and the swaging block 53, and the hydraulic jack 54 is operated so that the compression sleeve 52 is swaged. It can be seen that it is passing through block 53.

At this time, since the inner diameter of the swaging block 53 is smaller than the outer diameter of the compression sleeve 52, compression force is generated in the compression sleeve 52 forcibly.

Since the compression sleeve 52 is a cylindrical sleeve that can be deformed by compression and is compressed using a swaging block 53, the compression sleeve 52 is fixed by fastening to a separate fixing device.

To this end, the compression sleeve 52 is usually subjected to screw tap processing for fastening and fixing to the fixing device. In (52), a screw tap that can pass through the swaging block 53 is preformed.

In the end, the tensioning and fixing work of the FRP tension member 51 using the compression type fixing device separately forms a screw tap on the compression sleeve 52, and after the compression sleeve 52 tensions the compressed FRP tension member 51, It is made by fastening the screw tap to the fixing device, which reduces workability due to additional processes such as screw tap processing of the compression sleeve 52, increases the extension length of the compression sleeve to form the screw tap, and separate fixing device Due to the difficulty of securing the settlement space due to the installation of the , there were limitations in workability and usability.

Republic of Korea Patent No. 10-0540372 (Title of Invention: Seismic Isolator Using Shape Memory Alloy Wire, Publication Date: January 10, 2006) Republic of Korea Patent No. 10-0622390 (Title of Invention: Column Structure Reinforcement System Using Pressing Means Made of Reinforced Steel Plate and Shape Memory Alloy, Publication Date: September 11, 2006) Republic of Korea Patent Publication No. 10-2011-0064708 (title of invention: tool holder and tool fixing method using shape memory alloy, publication date: June 15, 2011) Republic of Korea Patent Registration No. 10-2098014 (Title of Invention: Fixing device using shape memory alloy and its construction method, Publication date: April 7, 2020)

Therefore, in the present invention, in introducing prestress to a structure using a compression type fixing device for an FRP tension member, the FRP tension member can be fixed to the structure without installing a separate screw tap on the compression sleeve, and the compression type anchorage It is a technical task to solve the provision of a shape memory alloy compression anchorage with excellent workability and improved usability as the size can be minimized and a method for fixing the FRP tension member using the same.

In addition, in the shape-memory alloy compression anchorage where the tensile stress continues, the compression force is sufficiently introduced at the part where the shear stress is the largest, and additional compression force is effectively added to the FRP tension member through mechanical engagement. Therefore, it is a technical task to solve the provision of a shape memory alloy compression anchorage optimized for fixing FRP tension members and a method for fixing FRP tension members using the same.

Shape memory alloy compression anchorage of the present invention in order to achieve the above object,

A fixing block made in the form of a block using a shape memory alloy (SMA), which uses shape memory properties to fix the FRP tension member by being compressed into the fixing hole inside by heating; And the fixing hole diameter (D1) gradually increases as the distance from the fixing hole diameter (D2) of the portion where the shear stress is the largest in the fixing FRP tension member while passing through the other end surface from one end surface of the fixing block Including, a fixing hole formed to be large; the elastic memory in the fixing hole is formed so that the fixing hole at one end surface is compressed to the outer circumferential surface of the FRP tension member so that the diameter decreases from one end surface to the other end surface. The compression force applied around the lateral end surface acts the greatest in the entire fixing hole.

In order to achieve the above object, the FRP tension member fixing method using the shape memory alloy compression anchorage of the present invention is

(a) installing a sheath to the structure and inserting and installing the FRP tension member from the outside, setting one end to be exposed to the fixing part (A1) of the structure and the other end to be exposed to the fixing part (A2) of the structure; (b) forming a fixed anchorage at one end of the FRP tension member located at the fixing portion (A1) of the structure, and installing the shape memory alloy anchorage through the other end of the FRP tension member located at the anchoring portion (A2) of the structure; And (c) with one end of the FRP tension member fixed to the fixed anchorage as a fixed end, after passing through the shape memory alloy anchorage and tensioning one end of the FRP tension member located at the anchoring portion (A2) of the structure, heating the shape memory alloy anchorage It is to include; step of fixing one end of the FRP tension member to the shape memory alloy anchorage.

According to the present invention, since it is possible to minimize the compression type fixing device to the FRP tension member and fix it to the concrete structure, it is possible to introduce prestress to the concrete structure through the FRP tension member even if only a fixing space for fixing the conventional PC steel strands is provided. And it is possible to provide a shape memory alloy compression anchorage with improved workability and a FRP tension member anchoring method using the same.

In addition, the present invention can solve the problem of brittle fracture in the fixing area according to the characteristics of the FRP tension member, which is vulnerable to shear stress, by using a compression-type anchoring device for the FRP tension member, and can effectively introduce compression force, resulting in efficient tension operation. It is possible to provide a shape memory alloy compression anchorage and a FRP tension member anchorage method using the same.

Figure 1a is a stress-strain graph of a conventional shape memory alloy (SMA)
Figure 1b is application examples for concrete structures or other devices using a conventional shape memory alloy (SMA)
Figure 1c is an example of application of shape memory alloy (SMA) to a tool holder for fixing a conventional tool,
1d is an exemplary view of a fixing device using a conventional shape memory alloy;
Figure 1e is a drawing showing the ductility characteristics in the reinforcement method of a conventional reinforced concrete structure, an example of forming a compression type sleeve,
2 and 3 are a shape memory alloy anchorage and installation example of the present invention,
Figure 4 is an example of FRP tension member fixation using the shape memory alloy anchorage of the present invention,
Figure 5 is an exemplary view of the FRP tension member fixing method using the shape memory alloy compression anchorage of the present invention.

Hereinafter, embodiments of the present invention will be described in detail so that those skilled in the art can easily practice with reference to the accompanying drawings. However, the present invention may be embodied in many different forms and is not limited to the embodiments described herein. And in order to clearly explain the present invention in the drawings, parts irrelevant to the description are omitted, and similar reference numerals are attached to similar parts throughout the specification.

Throughout the specification, when a certain component is said to "include", it means that it may further include other components without excluding other components unless otherwise stated.

[Shape memory alloy anchorage 100 of the present invention]

Figures 2 and 3 is a shape memory alloy anchorage 100 and installation example of the present invention, Figure 4 shows an FRP tension member anchoring example using the shape memory alloy anchorage 100 of the present invention.

As shown in FIG. 2, the shape memory alloy anchorage 100 has an anchoring hole 120 formed so that the FRP tension member 200 penetrates the approximate central portion.

In the shape memory alloy anchorage 100, the shape memory alloy deformed at a low temperature, which is a characteristic of the shape memory alloy (SMA), maintains its deformed shape until heat is applied, but when heat is applied and the temperature rises, it returns to its original shape It uses shape memory properties.

Accordingly, the shape memory alloy anchorage 100 of the present invention is a anchorage used as a compression-type anchorage device for the FRP tension member 200 by heating (a method such as applying electricity), in particular, a shape memory alloy (SMA). It means.

Referring to FIGS. 3 and 4, the shape memory alloy anchorage 100 is installed so as to pass through the inside of the structure 300, and both ends are set to extend and expose to the outside of the structure 300. In the FRP tension member 200,

A fixing fixture 400 is installed at one end of the FRP tension member 200 so as to come into contact with the fixing part A1 of the structure 300 and serves as a fixing end,

It is installed as a kind of movable anchorage at the other end of the FRP tension member 200 that is tense at the anchorage portion A2 of the structure 300.

That is, in a state in which the other end of the FRP tension member 200 is tensed, the shape memory alloy anchorage 100 set in the anchoring portion A2 is heated by the heating means 500 using an electric light, so that the tensioned FRP The tension member 200 is to be fixed in the fixing hole 120 of the shape memory alloy anchorage 100.

Accordingly, the shape memory alloy anchorage 100 includes a anchoring block 110, a anchoring hole 120, and an inner protrusion 130, as shown in FIGS. 2 and 3.

As shown in FIGS. 2 and 3, the fixing block 110 is made of a shape memory alloy (SMA) in a block shape capable of various cross sections, and the FRP tension member 200 is fixed by heating using shape memory properties. In (A2), it uses the property of restoring to its original shape so that it is fixed to the fixing hole 120 inside the fixing block 110.

Accordingly, the fixing block 110 is formed so that the FRP tension member 200 penetrates, but the fixing hole 120 penetrates the inside so that the FRP tension member 200 is fixed from the inside by compression. In FIGS. 2 and 3, the square Although exemplified in the form of a block, it may include a cylindrical, rectangular cross-section rod member, and the like.

At this time, as shown in FIG. 2, the fixing hole 120 penetrates from one end surface 111 to the other end surface 112 of the fixing block 110, but from one end surface 111 to the other end surface 112 It can be seen that the diameter of the fixing hole 120 is gradually reduced (D1 ==> D2) as it goes to .

4, when the FRP tension member 200 is tensioned toward the other end surface 112 and is compressed and fixed to the inner surface of the fixing hole 120, the fixation block 110 occurs around the other end surface 112. Shear stress is the largest.

Since this can be fatal to the FRP tension member 200, which is vulnerable to shear stress, the present invention increases the compressive force around the other end surface 112 to respond to the shear stress, and one side end surface 111 is relatively sheared. Since the stress is small,

Accordingly, as shown in FIG. 2, the fixing hole 120 is formed as a tapered fixing hole 120 whose diameter gradually decreases from one end surface 111 to the other end surface 112 so that the corresponding compression force is introduced. The compression force around the other end surface 112 is to have the effect of making it larger than the one end surface 111.

That is, the elastic memory in the fixing hole 120 of the fixing block 110 is such that the fixing hole 120 on one side end surface 111 is compressed to the outer circumferential surface of the FRP tension member 200, so that the one side end surface 111 The compressive force applied to the fixing hole 120 around the other end surface 112 formed such that the diameter decreases toward the other end surface 112 is maximized in the entire fixing hole 120 .

At this time, the diameter of the fixing hole 120 does not change according to the diameter of the small fixing hole around the other end surface 112 without making the compression force introduced around the other end surface 112 larger than that of the one end surface 111. This is because when there is no difference in the compressive force to be, relatively excessive compressive force may be introduced around the one-side end surface 111 of the FRP tension member 200, which may be disadvantageous in securing the fixing performance of the FRP tension member 200.

Furthermore, in the present invention, as the diameter D2 around the other end surface 112 is smaller than the diameter D1 of the one end surface 111, the compression force introduced around the one end surface is reduced, and the mechanical engagement action is not the compression force. In order to supplement the compression force by the inner projection 130 is installed on the inner surface of the fixing hole 120 around the one end surface 111.

Next, as shown in FIGS. 2 and 3, the fixing hole 120 allows the fixing block 110 to penetrate from the one end surface 111 to the other end surface 112, but the compressive force on the fixed FRP tension member 200 It is formed so that the fixation hole diameter (D1) gradually increases as the distance from the fixation hole diameter (D2) of the largest part occurs.

In the case of FIG. 2 , a fixing hole 120 having a diameter D2 around the other end surface 112 smaller than the diameter D1 of the one end surface 111 is formed, and around the other end surface 112 The diameter (D2) of is determined so that the local stress to be brittle fracture by the largest shear stress in the FRP tension member 200 to be fixed after tension is restrained by the compression force to solve the problem caused by the concentration of the shear stress.

These fixing holes 120 are installed to pass through the fixing block 110, but at least one or more may be installed.

Next, as shown in FIG. 2, the inner protrusion 130 introduces a relatively small compression force into the fixing hole 120 around the one end surface 111 opposite to the other end surface 112, where the compression force is the largest. Considering that the fixing force may decrease, the inner protrusion 130 formed in the form of a spring made of SMA material on the inner surface of the fixing hole 120 around the one side end surface 111 is brought into contact with elasticity, as shown in FIG. When the pressing force acts as a kind of protrusion, it is intended to act as a fixing protrusion on the outer circumferential surface of the FRP tension member 200.

That is, since it is made of SMA material, it adheres to the inner surface of the fixing hole 120 around one end surface 111 due to the shape memory effect of restoring to its original shape when heated, and the fixing performance of the FRP tension member 200 increases due to the compressive force. can become

According to Figure 3 it can be confirmed an example of the installation of the FRP tension member 200 using the shape memory alloy anchorage (100).

At this time, the shape memory alloy anchorage 100 is such that the sheath 310 for the FRP tension member 200 formed in advance in the structure 300 is embedded.

When constructing the structure 300 with concrete, the sheath 310 is installed to be embedded in the inside in advance, and then both ends are exposed to the outside by concrete pouring and curing, and formed to penetrate the inside of the structure 300. will be.

Accordingly, the FRP tension member 200 is inserted into the sheath 310 so that the fixing fixture 400 serving as a fixed end while in contact with the fixing portion A1 of the structure 300 is installed in the FRP tension member 200,

The other end of the FRP tension member 200, which is tense at the anchoring portion A2 of the structure 300, penetrates the shape memory alloy anchorage 100 of the present invention, and the shape memory alloy anchorage 100 of the structure 300 Set to be in contact with the fixing part (A2),

After tensioning the other end of the FRP tension member 200 penetrating the shape memory alloy anchorage 100,

The shape memory alloy anchorage 100 is heated (applying electricity, etc.) so that the other end of the FRP tension member 200 is fixed to the inner surface of the anchoring hole 120 of the shape memory alloy anchorage 100.

Accordingly, as the strained FRP tension member 200 is settled in the shape memory alloy anchorage 100, prestress can be introduced into the structure 300, and the inside of the sheath 310 is filled with mortar or the like.

[Fixing method for FRP tension member 200 using shape memory alloy anchorage 100 of the present invention]

Figure 5 shows an example of the FRP tension member 200 fixing method using the shape memory alloy anchorage 100 of the present invention.

The fixing method of the FRP tension member 200 using the shape memory alloy anchorage 100 of the present invention fixes the FRP tension member 200 after tensioning the structure 300 constructed with concrete, so that the required prestress is introduced to the structure 300 can be considered as a method of repair and reinforcement.

Accordingly, the FRP tension member 200 is very effective in introducing prestress so that compressive stress is introduced into concrete where tensile stress occurs because there is no risk of corrosion and tensile strength is very excellent compared to conventional PC steel strands. When using a fixing device, the volume increases to secure the contact area with the FRP tension member, a separate fixing device must be installed on the structure 300, and there is a limit to deterioration in usability and workability due to screw tap processing. ,

When the shape memory alloy anchorage 100 of the present invention is used, even if the shape memory alloy anchorage 100 of a limited size is used when only the heating means 500 is provided, the necessary compression force can be designed by the shape memory to solve the problem. be able to solve

First, as shown in FIG. 5A, the sheath 310 is installed on the structure 300 and the FRP tension member 200 is inserted and installed from the outside, so that one end is exposed to the fixing portion A1 of the structure 300, and the other end It is set to be exposed to the anchoring portion A2 of the structure 300.

The structure 300 is a concrete structure to be subjected to prestress, and the sheath 310 is a pipe member through which the FRP tension member 200 used in the post-tension method is installed.

Accordingly, since concrete is not poured into the sheath 310, the FRP tension member 200 is inserted at the fixing part A1 of the structure 300 or the fixing part A2 of the structure 300 so that one end of the structure 300 It is exposed to the fixing part A1 of the structure 300, and the other end can be set to be exposed to the fixing part A2 of the structure 300.

Next, as shown in FIG. 5B, a fixed fixture 400 is formed at one end of the FRP tension member 200 located at the fixing part A1 of the structure 300, and the FRP located at the fixing part A2 of the structure 300 The shape memory alloy anchorage 100 is installed through the other end of the tension member 200.

The fixed fixture 400 is fixed to the other end of the FRP tension member 200 to be supported in contact with the fixing portion A1 of the structure 300, and is formed by fixing and installing a compression sleeve on the outer circumferential surface of the FRP tension member 200. You can do it.

At this time, it is preferable to install the fixing plate 410 between the fixing fixture 400 and the fixing part A1 of the structure 300 so as to secure a uniform holding force, and the fixing plate 410 is an FRP tension member. (200) may be used if it is formed in the form of a plate through which it passes.

Next, as described above, the shape memory alloy anchorage 100 is formed by including the anchoring block 110, the anchoring hole 120, and the inner protrusion 130, and the FRP tension member 200 is attached to the anchoring hole 120. It is exposed by allowing one end to penetrate.

Next, as shown in FIG. 5C, one end of the FRP tension member 200 fixedly installed in the fixed anchorage 400 is used as a fixed end, passing through the shape memory alloy anchorage 100 and located at the anchorage portion A2 of the structure 300 After tensioning one end of the FRP tension member 200, the shape memory alloy anchorage 100 is heated so that one end of the FRP tension member 200 is fixed to the shape memory alloy anchorage 100.

At this time, the heating of the shape memory alloy anchorage 100 includes a heating means 500 by electricity, and the fixing hole 120 of the shape memory alloy anchorage 100 by heating is restored to its original shape by FRP tension member ( 200) is compressed, and the compression force is relatively increased in the part where the shear stress is the largest in the FRP tension member 200, and the part where the shear stress is relatively small by using the inner protrusion 130 is mechanically struck. By the protrusion action, it is possible to additionally secure the required compression force.

Referring to FIG. 4, the inner protrusion 130 is elastic to the inner protrusion 130 formed in the form of a spring made of SMA material on the inner surface of the fixing hole 120 around the one-side end surface 111 of the shape memory alloy anchorage 100. It has been seen that it is made to contact by, and when the pressing force acts as a projection to act as a fixing projection on the outer circumferential surface of the FRP tension member 200.

The above description of the present invention is for illustrative purposes, and those skilled in the art can understand that it can be easily modified into other specific forms without changing the technical spirit or essential features of the present invention. will be. Therefore, the embodiments described above should be understood as illustrative in all respects and not limiting. For example, each component described as a single type may be implemented in a distributed manner, and similarly, components described as distributed may be implemented in a combined form.

The scope of the present invention is indicated by the following claims rather than the detailed description above, and all changes or modifications derived from the meaning and scope of the claims and equivalent concepts should be construed as being included in the scope of the present invention. do.

100: shape memory alloy anchorage
110: fixing block 111: one end surface
112: other end surface 120; settlement hall
130: inner projection 200: FRP tension member
300: structure 310: sheath
400: fixed fixture 410: fixing plate
500: heating means D1, D2: diameter of fixing hole
A1, A2: fixing area, fixing area

Claims (10)

A fixing block 110 made in a block form using a shape memory alloy (SMA), which uses shape memory properties so that the FRP tension member 200 is compressed and fixed to the fixing hole 120 therein by heating; and
It penetrates from the one side end surface 111 of the fixing block 110 to the other end surface 112, but based on the fixing hole diameter (D2) of the part where the shear stress is the largest in the fixed FRP tension member 200 A fixing hole 120 formed so that the fixing hole diameter D1 gradually increases as the distance increases;
The elastic memory in the fixing hole 120 is such that the fixing hole 120 at one end surface 111 is compressed to the outer circumferential surface of the FRP tension member 200, so that from one end surface 111 to the other end surface 112 An anchorage for compressing a shape memory alloy so that the compressive force applied around the other end surface 112 formed to have a smaller diameter acts the greatest in the entire fixing hole 120. According to claim 1,
An inner protrusion 130 formed in the form of a spring made of SMA material is further installed on the inner surface of the fixing hole 120 around the one end surface 111 of the fixing block 110, so that a compressive force acts on the inner protrusion 130. When done, the shape memory alloy compression anchorage to supplement the compression force by the mechanical engagement action on the outer circumferential surface of the FRP tension member 200 as a projection. According to claim 1,
The fixing block 110,
A block in which a fixing hole 120 is formed so as to pass through the other end surface 112 from one side end surface 111, but the diameter gradually decreases from one side end surface 111 to the other end surface 112. As, by heating the FRP tension member 200 is compressed and fixed to the inner surface of the fixing hole 120 shape memory alloy compression anchorage. According to claim 3,
The fixing hole 120,
The diameter D2 around the other end surface 112 of the fixing block 110 is smaller than the diameter D1 of the one end surface 111 of the fixing block 110, FRP tension member 200 fixed after tension In order to restrain the local stress to be brittle fracture by shear stress by pressing force, at least one shape memory alloy compression anchorage formed so as to penetrate the fixing block 110. According to claim 1,
The FRP tension member 200,
It is installed to pass through the inside of the structure 300 and both ends are set to extend and expose to the outside of the structure 300,
At one end of the FRP tension member 200, a fixing fixture 400 serving as a fixed end is installed so as to come into contact with the fixing part A1 of the structure 300, and at the fixing part A2 of the structure 300 A shape memory alloy compression anchorage for forming a shape memory alloy anchorage 100 as a movable anchorage at the other end of the tensioned FRP tension member 200. According to claim 5,
The sheath 310 for the FRP tension member 200 pre-formed in the structure 300 is embedded,
The FRP tension member 200 is inserted into the sheath 310 so that the fixing fixture 400 serving as a fixed end while in contact with the fixing portion A1 of the structure 300 is installed in the FRP tension member 200,
The other end of the FRP tension member 200, which is tense at the anchoring portion A2 of the structure 300, penetrates the shape memory alloy anchorage 100, and the shape memory alloy anchorage 100 is the anchoring portion of the structure 300 ( Set to touch A2),
After tensioning the other end of the FRP tension member 200 penetrating the shape memory alloy anchorage 100, the other end of the FRP tension member 200 is fixed to the inner surface of the fixing hole 120 of the shape memory alloy anchorage 100. An anchorage for compressing shape memory alloy. (a) The sheath 310 is installed on the structure 300, and the FRP tension member 200 is inserted and installed from the outside, so that one end is exposed to the fixing part A1 of the structure 300, and the other end is exposed to the structure 300 Setting to be exposed to the fixing part (A2) of the;
(b) A fixed fixture 400 is formed at one end of the FRP tension member 200 located at the fixing part A1 of the structure 300, and the FRP tension member 200 located at the fixing part A2 of the structure 300 Installing the shape memory alloy anchorage 100 through the other end of the; and
(c) With one end of the FRP tension member 200 fixed to the fixed anchorage 400 as a fixed end, the FRP tension member located at the anchoring portion A2 of the structure 300 through the shape memory alloy anchorage 100 ( 200) after tensioning one end, heating the shape memory alloy anchorage 100 so that one end of the FRP tension member 200 is fixed to the shape memory alloy anchorage 100; including, the shape of step (b) The memory alloy anchorage 100,
A fixing block 110 made in a block form using a shape memory alloy (SMA), which uses shape memory properties so that the FRP tension member 200 is compressed and fixed to the fixing hole 120 therein by heating; And to pass through the other end surface 112 from one side end surface 111 of the fixing block 110, but based on the fixing hole diameter D2 of the portion where the shear stress is greatest in the fixed FRP tension member 200 A fixing hole 120 formed so that the fixing hole diameter D1 gradually increases as it moves away from
The elastic memory in the fixing hole 120 is such that the fixing hole 120 at one end surface 111 is compressed to the outer circumferential surface of the FRP tension member 200, so that from one end surface 111 to the other end surface 112 A method of fixing FRP tension members using a shape memory alloy compression anchorage so that the compression force applied around the other end surface 112 formed to be small in diameter acts the greatest in the entire fixation hole 120. According to claim 7,
The heating of the shape memory alloy anchorage 100 in step (c) is,
In a state in which the other end of the FRP tension member 200 is tensed, the shape memory alloy anchorage 100 set in the anchoring portion A2 is heated by the heating means 500 so that the tensioned FRP tension member 200 is shaped memory FRP tension material fixation method using a shape memory alloy compression anchorage to be anchored in the anchorage hole 120 of the alloy anchorage 100. According to claim 7,
An inner protrusion 130 formed in the shape of a spring made of SMA material is further installed on the inner surface of the fixing hole 120 around the one end surface 111 of the fixing block 110 in step (b), so that the inner protrusion 130 ) FRP tension member fixation method using a shape memory alloy compression anchorage to supplement the compression force by mechanical engagement on the outer circumferential surface of the FRP tension member 200 as a projection when the compression force acts on the ). According to claim 7,
The fixing block 110 of step (b),
A block in which a fixing hole 120 is formed so as to pass through the other end surface 112 from one side end surface 111, but the diameter gradually decreases from one side end surface 111 to the other end surface 112. As, by heating, the FRP tension member 200 is compressed and fixed to the inner surface of the fixing hole 120,
The fixing block 110 is tapered so that the one side end surface 111 passes through the other side end surface 112, but the diameter gradually decreases from one side end surface 111 to the other side end surface 112. A block in which a fixing hole 120 is formed, FRP tension member fixing method using a shape memory alloy compression anchorage that allows the FRP tension member 200 to be pressed and fixed to the inner surface of the fixation hole 120 by heating.

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