KR100713834B1 - Fiber Reinforced Polymer Bar with Polyhedral Deformation - Google Patents

Abstract

According to the present invention, in order to support the shear force acting on the nodes, the shape of the space partitioned by the nodes and the ribs is fixedly formed into a polyhedral shape, and the ribs formed on one side and the ribs formed on the other side are mutually different from each other. The present invention relates to a fiber reinforced composite reinforcing bar that effectively resists the shear force acting on the node by being staggered.

Rebar, FRP, nodes, ribs

Description

Fiber Reinforced Polymer Bar with Polyhedral Deformation

1A, 1B, 1C and 1D show a conventional Bar or Rod type FRP rebar.

FIG. 1E illustrates a bar or rod-type FRP reinforcing bar wrapped with a release protrusion formed with a conventional circular rib and node.

Figure 2 shows the working state of the fiber reinforced composite reinforcement with a multi-sided node of the present invention.

Figure 3 shows the fiber reinforced composite reinforcement of Example 1 of the present invention.

Figures 4a and 4b shows a fiber reinforced composite reinforcement of Example 2 of the present invention.

Figures 5a and 5b shows the fiber reinforced composite reinforcement of Example 3 of the present invention.

6A, 6B, 6C, 6D, 6E, and 6F illustrate the fiber reinforced composite reinforcement of Example 4 of the present invention.

<Description of the symbols for the main parts of the drawings>

100: fiber reinforced composite reinforcement with polyhedral nodes

110,111,112,113,114,115,116: nodes

120,121,122,123,124,125: rib

130: inner core 200: inner core

300a, 300b: Semicircular release protrusion

A: faceted compartment

The present invention relates to a fiber reinforced composite reinforcing bar having a polyhedral node. More specifically, the present invention relates to a fiber reinforced composite reinforcement for a structure, which is embedded in a concrete structure including a reinforced concrete structure, is installed to increase adhesion with concrete, and has a release protrusion composed of nodes and ribs.

Concrete in the conventional concrete structure (Concrete) is strong in compression but weak in tension, it is to arrange the reinforcing bar in the place where the tensile stress is generated to bear the tensile stress. In other words, by reinforcing the reinforcement to the tensile stress acting on the concrete, concrete structure design and manufacturing method that takes full advantage of the material properties of the concrete and the reinforcement is currently used.

Reinforcing bars used in such concrete structures are widely used as concrete reinforcement materials because they have high compressive strength and tensile strength, and are relatively easy to process, and are ductiles that increase in strain without additional stress after yielding due to external load. Since the fracture behavior is characteristic, brittle fracture of the concrete structure can be prevented by adjusting the amount of reinforcing bars in the concrete.

In spite of these advantages, steel reinforces easily when exposed to the outside due to damage of concrete coating, which can reduce the durability of the structure, which has a significant impact on the safety of the structure, and the weight is quite large. There was a problem that requires a lot of effort and cost for the transportation and installation.

Therefore, it was required to develop a reinforcement of a concrete structure to replace these reinforcing bars, one of the things that can meet this need is a reinforcement made of fiber reinforced polymer (Fiber Reinforced Polymer) (hereinafter referred to as "FRP reinforcement").

The FRP reinforcement is lightweight, non-corrosive, excellent in insulation, and has been developed and put into practical use as a concrete reinforcement due to the advantages of high strength. Common composite fibers used in FRP reinforcement include carbon fibers, aramid fibers, glass fibers and the like.

In particular, in the case of FRP reinforcement used as a reinforcement for concrete structures, various application methods have been developed according to the use type and application object, such as sheet type or laminate type and bar or rod type such as reinforcing bar. This is the case with FRP stiffeners.

Figures 1a, 1b, 1c and 1d show a commercially available bar or rod type FRP reinforcement with a woven release protrusion in particular.

Bar or rod-type FRP stiffener 10 of Figure 1a has a constant nominal diameter, so that the spiral rough surface 11 is formed by braiding to improve the adhesion to the concrete on the shell of the inner core material One,

The bar (Bar or Rod) type FRP reinforcement 20 of Figure 1b has a constant nominal diameter, and the woven material 21 is formed on the outer surface of the reinforcement material by twisting the rope on the outer core material,

Bar or Rod-type FRP reinforcement of Figure 1c is a hybrid FRP reinforcement is to form the woven material 31 in the form of a net on the outer shell of the inner core material,

Bar or rod-type FRP reinforcement 40 of Figure 1d is to process the outer core material to the vertical annular node 41 is continuously spaced to form a woven fabric.

In general, the attachment mechanism of the bar-shaped FRP stiffeners (10, 20, 30, 40) to the concrete is made by chemical adhesive force, friction with concrete, and bearing pressure. It has been reported to be controlled by interlocking between concrete and release protrusions formed on the shell of stiffeners.

However, in the case of the FRP reinforcement (10, 20, 30) of Figures 1a to 1c to form a protrusion (Interforming) that can be sufficiently interlocking with the concrete in the form of protrusion of the woven fabric formed around the inner core material (Deformation) There was a problem that is difficult to make,

In the case of Fig. 1d, although the vertical annular section of the FRP material is formed to protrude considerably, in the manufacturing process, since the outer circumferential surface of the inner core material is deformed into a convex and concave shape using a roller, a large pressure is applied to the inner core material. It is pointed out that the cutting phenomenon of the inner core material may occur, and above all, the tensile strength and stiffness of the overall reinforcement may be reduced due to the bend from the outer circumferential surface of the inner core material.

Bar or rod-type FRP stiffener 50 of Figure 1e is a release projection 60 made of a circular synthetic resin formed integrally with the node 61 and the rib 62 on the outer shell of the inner core similar to the reinforcing bar It will be wrapped to form.

However, the task of completely attaching the release protrusion 60 integrally to the entire inner circumferential surface of the inner core material is very difficult, and in view of the characteristics of the release protrusion made of synthetic resin (polystyrene, vinyl chloride, polyester, etc.), shear strength It was pointed out that compared to the reinforcing bar is very low, the shear failure of the node of the FRP stiffener occurs even at a very low load compared to the deformed bar.

It is an object of the present invention to provide a bar or rod-type FRP reinforcement manufacturing method formed on the outer shell with a release protrusion consisting of nodes and ribs that can effectively resist shear strength.

The present invention to achieve the above technical problem,

In the fiber reinforced polymer body reinforcement (100) formed by continuously forming a plurality of ribs formed between the node, the node and the node in the inner core material,

In order to support the shear force acting on the node 110, the shape of the space partitioned by the node 110 and the rib 120 is fixed to the polygonal shape (A), to one side relative to the node 110 The formed ribs and ribs formed on the other side are formed to form a release protrusion on the inner core material 130 to allow the ribs to be staggered to each other, thereby effectively dispersing the shear force acting on the node 110.

The operation of the node 110 and the rib 120 of the present invention will be described below with reference to FIG.

The fiber reinforced polymer body reinforcement 100 of FIG. 2 is formed with an inner core 130, a vertically formed node 110 and a horizontally formed rib 120, by the node 110 and the rib 120. The shape of the partitioned space is formed in a rectangular shape.

Based on the node 110, the left and right ribs 120a and 120b are horizontally formed at predetermined intervals on the left side, and the left and right ribs are formed between the upper and lower ribs on the right side. The ribs 120c are horizontally formed while being staggered at right angles.

At this time, when the shear force F due to mechanical interlocking with concrete acts on the node 110 from the left side, the ribs 120a and 120b formed up and down on the left side of the node 110 are compressed support members. As a result, the shear force is resisted.

In this case, the node 110 receives a force pushing in the left direction, and thus, in the case of the rib 120c formed on the right side of the node, the node 110 resists shear force as a tension supporting member.

As a result, the ribs 120a, 120b, and 120c, which are alternately formed on the left and right sides of the node 110, efficiently support the shear force as the compressive support and the tension support member, so that the release protrusions composed of the multi-faceted nodes and the ribs more efficiently. It can be made to resist the shear force acting.

As described above, the ribs are alternately arranged on both sides with respect to the nodes (hereinafter referred to as "crossing arrangement method"). In the present invention, the shape A of the space partitioned by the nodes and the ribs is fixedly formed into a multi-sided shape. A method is adopted, and the present invention introduces the following three embodiments with respect to the shape A of the space partitioning into these polyhedrons.

<Example 1>

In the first embodiment, when the release protrusion is formed around the inner core 130 of the FRP reinforcement, the shape A of the space partitioned by the node 110 and the rib 120 is formed in a rectangular shape.

Figure 3 shows a perspective view and a front view of a fiber reinforced composite reinforcement having a multi-faceted node according to the first embodiment.

Accordingly, the nodes 111, 112, 113, 114, 115, 116, 117 and 118 are vertically spaced apart in the longitudinal direction from the inner core 130 in the longitudinal direction and are continuously formed in the shape of an annular node is wound around the inner core 130 is installed in a ring shape.

Based on the node 115 located at the center of the node 110, ribs 121, 122, and 123 are horizontally formed on both sides of the node 115, and each rib 121, 122, and 123 is formed based on the node 115. It is formed while stepping at right angles to each other up and down.

As a result, the fiber reinforcement composite reinforcing bar having the multi-faceted node of Example 1 can be installed in the staggered arrangement method according to the action of the present invention, the node 110 and the rib 120 described above.

The node 110 and the rib 120 installed by the staggered arrangement method may be continuously manufactured integrally with the inner core material or continuously attached to the inner core material 130 by an adhesive such as an epoxy resin.

<Example 2>

In the second embodiment, as a modification of the first embodiment, in forming a release protrusion around the inner core 130 of the FRP reinforcement, the shape A of the space partitioned by the node 110 and the rib 120 is hexagonal. In the case of forming in the form.

4A and 4B show a perspective view and a front view of the fiber reinforced composite reinforcement 100 having a multi-faceted node according to the second embodiment.

Accordingly, the nodes 110; 111, 112, 113, 114, and 115 are vertically spaced apart in the longitudinal direction from the inner core member 130 in a zigzag in the vertical direction, and are also formed in the shape of an annular node, which is wound around the inner core member and installed in a ring shape.

Based on one node 113 located at the center of the node 110, ribs 121, 122, and 123 are horizontally formed on both sides of the node 113, but each rib 121, 122, and 123 is a node 113. As a reference, they are inclined alternately up and down to form a step.

As a result, the fiber reinforced composite reinforcing bar having the multi-faceted node of Example 2 may be installed in the staggered arrangement method of the node 110 and the rib 120 described above.

The node 110 and the rib 120 installed by the staggered arrangement method may be continuously manufactured integrally with the inner core material or continuously attached to the inner core material 130 by an adhesive such as an epoxy resin.

In addition, if one side rib 122 of the ribs formed to cross each other as a reference, unlike the first embodiment, because the nodes 113, 113a, 113b is formed to be inclined in a jig zag in the form of an arch for the shearing force acting local form There is an effect that the resistance is more effective to enable the resistance of the shear force.

<Example 3>

The third embodiment is a modification of the first and second embodiments to form a release protrusion around the inner core 130 of the FRP reinforcement, the shape (A) of the space partitioned by the node 110 and the rib 120 In the case of forming a rhombus.

Figures 5a and 5b shows a perspective view and a front view of the fiber reinforced composite reinforcement having a multi-faceted node according to the third embodiment.

Accordingly, the nodes 110; 111, 112, 113, 114, and 115 are vertically spaced apart in the longitudinal direction from the inner core member 130 in a zigzag, and are continuously formed in the shape of an annular node, and are wound around the inner core member and are installed in a ring shape.

Based on the node 113 located at the center of the node 110, the ribs 121, 122, and 123 are formed on both sides of the node 113, respectively, and each rib 121, 122, and 123 is based on the node 113. As the up and down to cross each other to be also inclined to form a step, as a whole, as if the node 110 is formed continuously to form the appearance.

As a result, the fiber reinforcement composite reinforcement composite having a multi-faceted node of Example 3 can also be installed in the staggered arrangement method described above.

The node 110 and the rib 120 installed by the staggered arrangement method may be continuously manufactured integrally with the inner core material or continuously attached to the inner core material 130 by an adhesive such as an epoxy resin.

In addition, when one side rib 123 of the ribs formed to cross each other as a reference, as in the second embodiment, since the nodes (113; 113a, 113b) is inclined in a jig zag resistance in the arch form against the shear force acting in the local form There is an effect that it is possible to have a more effective resistance of the shear force.

<Example 4>

In the case of the embodiments 1, 2, and 3 described above, it may be difficult to continuously form the multi-faceted compartment A in the outer core of the inner core. 6a to 6f, the semicircular release protrusions 300a and 300b formed with the nodes and the ribs, respectively, may be installed while wrapping the inner core member 130, and the ends of the release protrusions may be compressed and connected to each other.

6A and 6B, the semicircular release protrusions 300a and 300b are applied in Example 1, and there is no separate rib-shaped connection junction in the connection portion of each semicircular release protrusion. The case of FIG. 6B is a case where there is a separate rib-shaped connection junction portion 300c.

6C and 6D, the semicircular release protrusions 300a and 300b are applied in Example 2,

6E and 6F, the semicircular release protrusions 300a and 300b are applied in the third embodiment.

According to the fiber reinforced composite reinforcing bar having a multi-bar node of the present invention, since the rib is installed as a tension and compression support member based on the bar can be a more effective shear force resistance form, the shear resistance of the release protrusion can be increased Will be

It is possible to maximize the shear resistance by the arch action of the nodes connected to each other, it is possible to have the largest adhesion strength as FRP reinforcement,

When manufactured by attaching the semi-circular release protrusions can have a rationality of production.

An embodiment of the present invention described above and illustrated in the drawings should not be construed as limiting the technical spirit of the present invention. The protection scope of the present invention is limited only by the matters described in the claims, and those skilled in the art can change and change the technical idea of the present invention in various forms. Therefore, such improvements and modifications fall within the protection scope of the present invention as long as it will be apparent to those skilled in the art.

Claims (4)

In the fiber reinforced polymer body reinforcing bar in which a plurality of ribs formed between the nodes and the nodes between the inner core material outer shell, In order to support the shear force acting on the node, the shape of the space partitioned by the node and the rib is fixed in a polyhedral shape so that ribs formed on one side and ribs formed on the other side are alternately positioned with respect to the node. To effectively resist the shear force acting, the nodes and ribs are formed integrally around the inner core material continuously, or the semi-circular release protrusions formed with the nodes and ribs are wrapped around the inner core material, so as to be crimped and connected. Fiber reinforced composite reinforcement with polyhedral nodes. The fiber reinforced composite reinforcement according to claim 1, wherein the convex space is formed in a quadrangular shape and horizontal ribs are alternately formed on both sides at right angles with respect to the nodes, with vertical gaps intersecting each other. The fiber reinforced composite reinforcement composite according to claim 1, wherein the partitioned space is formed in a rhombus shape or a hexagonal shape so that the nodes and the ribs are connected to each other by being inclined to each other so that they cross each other to resist the shear force in the shape of an arch. . delete

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