KR102219654B1 - Reinforcing Method for Column using FRP and CRC board - Google Patents

Abstract

In the present invention, the FRP sheet is attached to the surface of a concrete column or a CFT (Concrete Filled Tube) column to increase the strength, and a cement board in the form of a unit member divided in the longitudinal direction is continuous in the transverse direction on each side of the column. FRP sheet and longitudinal direction to prevent damage or separation of the cement board by attaching multiple pieces to improve the vulnerable properties of fire, such as adhesives, while allowing the cement board segmented in the longitudinal direction to flow simultaneously with the pillars in external impacts such as earthquakes. It relates to a method of reinforcing a column using a cement board segmented in a row.
In a preferred embodiment of the present invention, (a) a board coupling member including coupling bolts at regular intervals in the transverse direction so as to protrude from the outer surface of the mounting plate and the mounting plate in the longitudinal direction of each side of the column to remove foreign matter from the column surface Installing the upper and lower portions; (b) wrapping the FRP sheet after applying the epoxy to the surface of the pillar; (c) applying a mortar to the surface of the FRP sheet to a predetermined thickness; (d) attaching a corner stiffener having a b-shaped cross section to each corner of the column; (e) On the surface of the column in the section between the corner stiffener and the corner stiffener, a longitudinally segmented cement board formed with a length equal to the length of the column and each having a connecting hole at both ends in the longitudinal direction is joined to the bonding bolt of the board bonding member. It includes a step of installing through the ball and combining with a nut to continuously attach in the transverse direction of each side of the column.

Description

Reinforcing Method for Column using FRP and CRC board using FRP sheet and longitudinally segmented cement board

The present invention relates to a method for reinforcing a pillar using an FRP sheet and a cement board segmented in a longitudinal direction, and more particularly, to a concrete pillar or a CFT (Concrete Filled Tube) column to increase the strength by attaching the FRP sheet to the surface of the column. In addition, a plurality of cement boards in the form of unit members segmented in the longitudinal direction are attached to each side of the column in a horizontal direction to improve the vulnerable properties of fires such as adhesives, while vertical displacement occurs in the column due to earthquakes. A method of reinforcing a column using an FRP sheet that prevents the cement board from being damaged or separated by absorbing the energy transmitted by allowing the cement board segmented in the direction to behave simultaneously with the pillar at both ends in the longitudinal direction and the cement board segmented in the longitudinal direction. It is about.

In recent years, demands for seismic reinforcement of structures are increasing not only for structural repair and reinforcement due to increased strength of existing structures and deterioration of durability due to environmental problems, but also due to aging of structures or reinforcement of seismic regulations. As methods to improve the repair, reinforcement and seismic performance of existing structural members, the section enlargement method or the steel plate reinforcement method has been widely used, but since the 1990s, it has several advantages compared to other materials and construction methods. The use of reinforcement methods using FRP is increasing. As a result, a method of sealing with a sealing material such as an epoxy resin, a method of injecting a grout material such as an epoxy-based adhesive, and a method of reinforcing using a putty material have been developed and are used for repair and reinforcement of structures.

However, the reinforcing method using the FRP sheet has a problem that the epoxy-based adhesive used to attach the FRP sheet is vulnerable to a heat source, so in case of fire, it is separated from the column or the structural stability of the column is threatened.

As a background technology of the present invention, there is Patent Registration No. 00708058 "FRP Panel for Reinforcing Concrete Structures" (Patent Document 1). In the background art, as shown in FIG. 5, the top/bottom of the panel for reinforcing the structure of reinforced concrete is configured, and the top/bottom epoxy mortar is composed of a mixed fine aggregate and epoxy resin mixed with silica sand No. In the FRP panel for reinforcement of a concrete structure, which is inserted in between and composed of a carbon FRP sheet for increasing the strength of the panel, the epoxy mortar is a mixture of fine aggregates mixed with the silica sand No. 60 and No. 4 in a ratio of 1:3. Next, an FRP panel for reinforcing concrete structures is proposed, which is manufactured by mixing the epoxy resin and the mixed fine aggregate at a ratio of 1:4.

However, the background technology is also vulnerable to a heat source because the FRP sheet is covered with epoxy, so in case of fire, there is a problem that it is separated from the column or the structural stability of the column is threatened.

Patent Registration No. 00708058 "FRP Panel for Reinforcing Concrete Structures"

The present invention is to solve the above problems, by attaching an FRP sheet to the surface of a concrete column or a CFT (Concrete Filled Tube) column to increase the strength, and a cement board in the form of a unit member segmented in the longitudinal direction The cement boards segmented in the longitudinal direction are attached to each side of the pillar so that it is continuous in the transverse direction to improve the vulnerable properties of fires such as adhesives. It is an object of the present invention to provide a method for reinforcing a column using an FRP sheet and a cement board segmented in the longitudinal direction by absorbing the energy transmitted by allowing it to behave at the same time and preventing the cement board from being damaged or separated.

The present invention (a) to remove foreign substances from the surface of the column, and install a board coupling member consisting of coupling bolts at regular intervals in the transverse direction so as to protrude to the outer surface of the mounting plate and the mounting plate in the longitudinal upper and lower ends of each side of the column. Step to do; (b) wrapping the FRP sheet after applying the epoxy to the surface of the pillar; (c) applying a mortar to the surface of the FRP sheet to a predetermined thickness; (d) attaching a corner stiffener having a b-shaped cross section to each corner of the column; (e) On the surface of the column in the section between the corner stiffener and the corner stiffener, a longitudinally segmented cement board formed with a length equal to the length of the column and each having a connecting hole at both ends in the longitudinal direction is joined to the bonding bolt of the board bonding member. It is intended to provide a method for reinforcing a column using an FRP sheet and a cement board segmented in a longitudinal direction, comprising; the step of attaching a ball in the horizontal direction of each side of the column by inserting and installing it and combining it with a nut. .

In addition, in step (b), the FRP sheet is an aramid fiber sheet (Aramid Fiber Reinforced Polymer, AFRP) to provide a column reinforcement method using the FRP sheet and the cement board segmented in the longitudinal direction.

In addition, in step (d), it is intended to provide a column reinforcement method using an FRP sheet and a cement board segmented in the longitudinal direction, characterized in that the corner stiffener is made of the same material as the cement board segmented in the longitudinal direction.

In addition, in step (d), the corner stiffener has a buffer member having a certain thickness at the outer end of the corner stiffener, so that the space between the cement board and the corner stiffener divided in the longitudinal direction is always kept tightly. And it is intended to provide a method for reinforcing columns using cement boards segmented in the longitudinal direction.

In addition, in step (a), an anchor portion is formed to protrude to the inner surface of the board coupling member attachment plate, and an anchor hole corresponding to the anchor portion is formed on the outer surface of the column, so that the anchor portion is inserted into the anchor hole to be installed. It is intended to provide a method for reinforcing a column using an FRP sheet and a cement board segmented in a longitudinal direction.

In addition, in step (a), a nut groove having a size larger than the diameter of the coupling hole is formed at a predetermined depth on the outer surface where the coupling hole of the cement board segmented in the longitudinal direction is formed, and in step (e), the nut It is intended to provide a column reinforcement method using an FRP sheet and a cement board segmented in a longitudinal direction, characterized in that the is embedded in the nut groove and does not protrude to the outside.

In the method for reinforcing a column using an FRP sheet and a cement board of the present invention, an FRP sheet is attached to the surface of a concrete column or a CFT (Concrete Filled Tube) column to increase the strength, and the unit member type segmented in the longitudinal direction A plurality of cement boards are attached to each side of the column in a transverse direction to improve the vulnerable properties of fires such as adhesives, while the longitudinally segmented cement boards axially extend both ends in the longitudinal direction when horizontal displacement occurs in the column due to earthquakes. It has a very useful effect in that the cement board is not damaged or separated by absorbing the transmitted energy by allowing it to behave simultaneously with the pillar.

The following drawings attached to the present specification illustrate preferred embodiments of the present invention, and serve to further understand the technical idea of the present invention together with the detailed description of the present invention, so the present invention is limited to the matters described in the accompanying drawings. It is limited and should not be interpreted.
1 to 5 are diagrams showing a method of reinforcing a column using an FRP sheet and a cement board segmented in a longitudinal direction according to the construction sequence of the present invention.
6 is a cross-sectional view and a partially enlarged view of FIG. 5.
Figure 7 is an embodiment showing the behavior when a lateral force acts on a column reinforced by a column reinforcement method using an FRP sheet and a cement board segmented in the longitudinal direction of the present invention.

In the following, the present invention will be described in detail with reference to the embodiments shown in the accompanying drawings, but the disclosed embodiments are illustrative for a clear understanding of the present invention, and the present invention is not limited thereto.

Hereinafter, the technical configuration of the present invention will be described in detail according to a preferred embodiment.

1 to 5 are diagrams illustrating a method for reinforcing a column using an FRP sheet and a cement board segmented in a longitudinal direction of the present invention in the order of construction, and FIG. 6 is a cross-sectional view and a partial enlarged view of FIG. 5.

First, as shown in Fig. 1, to remove foreign substances on the surface of the pillar 1, and install the board coupling member 11 to construct the cement board 60 segmented in the longitudinal direction in the step described later (a) .

The pillar (1) may be a concrete pillar or a CFT (Concrete Filled Tube) pillar, and various contaminants that interfere with adhesion such as laitance, dust, oil, and existing old coatings on the surface of the pillar (1). This is the step of cleanly removing with a grinder, sandblast, or high-pressure water.

The board coupling member 11 is composed of an attachment plate 111 and a coupling bolt 112 formed to protrude to the outer surface of the attachment plate 111, so that the board is joined after removing foreign substances from the surface of the column 1 The member 11 is installed at the upper and lower ends in the longitudinal direction of each side of the column 1.

The attachment plate 111 is configured to have the same length as the width of the pillar 1 and is installed horizontally at the upper and lower ends of each side of the pillar 1, and the coupling bolt 112 formed on the attachment plate 111 is It is formed at regular intervals in the longitudinal direction of the attachment plate 111, that is, in the transverse direction of the pillar 1.

The distance at which the coupling bolt 112 is formed is formed to be the same as the width of the cement board 60 segmented in the longitudinal direction.

The board coupling member 11 is attached to the surface of the pillar 1 by using a separate adhesive, etc. for attachment to the pillar 1, and the corner stiffener 50 when installing the corner stiffener 50 in the step described later The mounting plate 111 may be positioned to be fixed on the inside of the board, and the anchor part 113 is formed so as to protrude to the inner surface of the board coupling member 11 and the mounting plate 111, and the column 1 An anchor hole 12 corresponding to the anchor portion 113 may be formed on the outer surface of the anchor hole 12 to be installed by inserting the anchor portion 113 into the anchor hole 12.

Thereafter, as shown in FIG. 2, after applying the epoxy 20 to the surface of the pillar 1, the FRP sheet 30 is wrapped (b).

After removing foreign substances from the surface of the pillar 1 in the above step, the epoxy 20 is applied to the surface of the pillar 1 and then the FRP sheet 30 is wrapped.

Epoxy 20 is applied to the surface of the pillar 1, and is applied to form an adhesive force with the FRP sheet 30 to be wrapped later and to form a thick film on the surface of the pillar 1.

The FRP sheet 30 is wrapped on the surface of the pillar 1, and the FRP sheet 30 is impregnated with epoxy 20 to be integrated.

In the present invention, a thermosetting composite material, FRP sheet, is used.FRP (Fiber Reinforced Plastics) refers to fiber-reinforced plastics, by adding various inorganic substances (Fiber-based) to synthetic polymer materials to improve specific properties and functions. It refers to a polymer composite material used for purposes such as imparting.

Depending on the type of resin used, FRP is largely divided into thermosetting composite materials (FRTs; Fiber Reinforced Thermosets) and thermoplastic composite materials (FRTp; Fiber Reinforced Thermoplastics). In the 1960s, as fibers having excellent strength and elasticity, such as glass fiber, carbon, and aramid fiber, as well as thin fibers with a diameter of 6 to 10 μm were developed, polymer materials with strength and elasticity comparable to metals appeared. The thermosetting composite material is usually a combination of glass fiber and unsaturated polyester resin.

Preferably, the FRP sheet 30 may be made of an aramid fiber sheet (Aramid Fiber Reinforced Polymer, AFRP), and the aramid fiber has a stiffness of about 1/2 to 2/3 compared to steel, but the tensile strength is 1.5 compared to steel. It is more than twice as high and has excellent ductility among fiber-based reinforcements.

The FRP sheet 30 may be configured to adjust the amount of reinforcing strength through the thickness, the number of times the column 1 is wrapped, and the attachment range.

Thereafter, as shown in FIG. 3, the mortar 40 is applied to the surface of the FRP sheet 30 at a predetermined thickness (c).

The mortar 40 is used to attach the corner stiffener 50 and the cement board 60 segmented in the longitudinal direction in the steps to be described later, and the mortar 40 with a predetermined thickness on the surface of the FRP sheet 30 To apply.

Thereafter, as shown in FIG. 4, to attach the corner stiffener 50 of the b-shaped cross section to each corner of the column (1) (d).

Corner stiffener 50 is made to have a b-shaped cross section to improve the workability of the corner of the column (1), may be made of a semi-incombustible material, preferably made of the same material as the cement board 60 segmented in the longitudinal direction. I can.

The corner stiffener 50 is installed in the entire length on the pillar 1, and may be attached in an unsegmented state, or may be segmented into a predetermined length to be installed.

In particular, the corner stiffener 50 has a buffer member 51 having a certain thickness at the outer end thereof, so that the elasticity of the buffer member 51 causes the cement board 60 and the corner stiffener 50 to be segmented in the longitudinal direction. You can also try to keep the space tight at all times.

The buffer member 51 may be made of a rubber material or may be made of a refractory material made of EVA (ETHYLENE VINYL ACETATE) as a main material.

Finally, as shown in FIG. 5, the surface of the column 1 in the section between the corner stiffener 50 and the corner stiffener 50 includes a cement board 60 segmented in the longitudinal direction in the transverse direction of each side of the column 1 (E).

The cement board 60 segmented in the longitudinal direction is to protect the epoxy 20 adhesive applied to the surface of the FRP sheet 30 and the column 1 from a heat source, and is a cement board made of a semi-non-combustible material. Consists of

As shown, the cement board 60 segmented in the longitudinal direction is formed of a unit member in the shape of a long plate so that a plurality of them can be continuously attached to each side of the column 1 in the transverse direction.

The board coupling member 11 allows the coupling bolt 112 to protrude to the outside even after steps (b) to (c), and in step (e), the coupling of both ends in the longitudinal direction of the cement board 60 segmented in the longitudinal direction The ball 61 can be inserted into the coupling bolt 112 so that it is coupled with the nut 13.

At this time, a nut groove 62 having a size larger than the diameter of the coupling hole 61 is formed at a predetermined depth on the outer surface where the coupling hole 61 of the cement board 60 segmented in the longitudinal direction is formed, and the nut 13 ) When coupled, the nut 13 may be embedded in the nut groove 62 so that it does not protrude to the outside.

Figure 7 is an embodiment showing the behavior when a lateral force acts on a column reinforced by a column reinforcement method using an FRP sheet and a cement board segmented in the longitudinal direction of the present invention.

With this configuration, as shown in FIG. 7, when the seismic lateral force is generated, the cement board 60 segmented in the longitudinal direction acts by twisting the coupling bolts 112 fixed to the upper and lower portions, respectively, to absorb energy. There is.

In the method for reinforcing a column using the FRP sheet and the cement board of the present invention as described above, the FRP sheet is attached to the surface of the concrete column or CFT (Concrete Filled Tube) column to increase the strength, and the unit segmented in the longitudinal direction A plurality of member-shaped cement boards are attached to each side of the column in a horizontal direction to improve the vulnerable properties of fires such as adhesives, while the cement boards segmented in the longitudinal direction when horizontal displacement occurs due to earthquakes, etc. There is a very useful effect of preventing the cement board from being damaged or separated by absorbing the energy transmitted by allowing both ends to move simultaneously with the pillar by the axis.

Until now, the present invention has been described in detail with reference to the presented embodiments, but those of ordinary skill in the art can make various modifications and modifications without departing from the technical spirit of the present invention with reference to the presented embodiments. will be. The present invention is not limited by such modifications and modifications, but is limited by the claims appended below.

1: pillar
11: board coupling member
111: attachment plate
112: coupling bolt
113: anchor part
12: anchor hole
13: nut
20: epoxy
30: FRP sheet
40: mortar
50: Corner stiffener
51: buffer member
60: cement board segmented in the longitudinal direction
61: coupling hole
62: nut groove

Claims (6)

(a) Remove foreign substances from the surface of the pillar (1),
A board coupling member 11 comprising the coupling bolts 112 at regular intervals in the transverse direction so as to protrude to the outer surface of the attachment plate 111 and the attachment plate 111 in the longitudinal direction upper and lower ends of each side of the column 1 Installing;
(b) wrapping the FRP sheet 30 after applying the epoxy 20 to the surface of the pillar 1;
(c) applying a mortar 40 to a predetermined thickness on the surface of the FRP sheet 30;
(d) attaching the corner stiffener 50 of the b-shaped cross section to each corner of the column (1);
(e) On the surface of the column (1) in the section between the corner stiffener 50 and the corner stiffener 50,
The cement board 60, which is formed to have the same length as the length of the column 1 and has the coupling holes 61 at both ends in the longitudinal direction, is connected to the coupling bolt 112 of the board coupling member 11 FRP sheet and a cement board segmented in the longitudinal direction, characterized in that comprising; and installing the ball (61) by inserting it and connecting it with a nut (13) to continuously attach in the transverse direction of each side of the column (1) Column reinforcement method using. The method according to claim 1,
In step (b),
The FRP sheet 30 is an aramid fiber sheet (Aramid Fiber Reinforced Polymer, AFRP), characterized in that the FRP sheet and the column reinforcement method using a cement board segmented in the longitudinal direction. The method according to claim 1,
In step (d),
Corner stiffener 50 is a column reinforcement method using the FRP sheet and the cement board segmented in the longitudinal direction, characterized in that made of the same material as the cement board 60 segmented in the longitudinal direction. The method according to claim 1,
In step (d),
The corner stiffener 50 is characterized in that a buffer member 51 of a certain thickness is formed at the outer end, so that the space between the cement board 60 and the corner stiffener 50 divided in the longitudinal direction is always tightly maintained. Post reinforcement method using FRP sheet and cement board segmented in the longitudinal direction. The method according to claim 1,
In step (a),
An anchor portion 113 is formed so as to protrude to the inner surface of the board coupling member 11 attachment plate 111,
An FRP sheet, characterized in that the anchor hole 12 corresponding to the anchor part 113 is formed on the outer surface of the column 1, and the anchor part 113 is inserted into the anchor hole 12 to be installed. A method for reinforcing columns using cement boards segmented in the longitudinal direction. The method according to claim 1,
In step (a),
A nut groove 62 having a size larger than the diameter of the coupling hole 61 is formed at a predetermined depth on the outer surface where the coupling hole 61 of the cement board 60 segmented in the longitudinal direction is formed,
In step (e),
When the nut 13 is coupled, the nut 13 is embedded in the nut groove 62 so that it does not protrude to the outside. A method for reinforcing a column using an FRP sheet and a cement board segmented in a longitudinal direction.

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