KR20170132617A - Precast composite reinforced concrete girder and method for manufacturing of the same - Google Patents

Abstract

A synthetic concrete girder of the present invention is a concrete girder provided with a flange and an abdomen plate vertically arranged on the flange, comprising: a concrete portion forming the flange and the abdomen plate by being cured on concrete; a main reinforcing bar arranged inside the concrete portion; and a wire mesh portion in which at least a portion of the wire mesh portion is arranged adjacent to the main reinforcing bar and is arranged inside the concrete portion, thereby controlling a tensile crack and a yarn tension crack of the concrete structure.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a composite concrete girder,

The present invention relates to a synthetic concrete girder and a method of manufacturing the same, and more particularly, to a synthetic concrete girder having a structure capable of controlling tensile cracks and sinusoidal heat of a concrete structure and a manufacturing method thereof.

With the development of construction technology, various studies and manufacturing of construction bridges have been made.

In addition, the durability and performance of bridges are strengthened by the development of various materials besides the structural method. Recently, for example, ultra high performance concrete has been developed which improves the performance of concrete and has improved high strength and tensile performance, and attempts to apply it as a bridge structure are continuously increasing.

This UHPC concrete has been developed to greatly reduce the compressive strength and tensile strength of concrete and to reduce the thickness of the structure to enable the construction of lightweight structures.

On the other hand, as an example of the prior art, Japanese Patent Application Laid-Open No. 10-2015-0132807 discloses a prestressed girder using a concrete girder and a tension member. However, in the case of such a conventional concrete girder, since the possibility of tensile and shear cracks is very high because the concrete portion is not reinforced, the girder section is formed to be very thick, which is an uneconomical method.

In addition, although the compressive performance of the ultra high performance concrete structure is greatly improved, the tensile strength is limited to about one tenth of the compressive strength.

Figure 1 shows cracks and fracture behavior due to conventional ultra high performance concrete structures. In the case of UHPC bridges and structures, there is a high possibility of cracking in the bottom plate of the bridge due to the momentum. In the case of UHPC bridges and structures, fracture due to cracks is dominant due to tensile stress during shear action. It is essential to develop technology that can prevent destruction.

KR 10-2015-0132807 A

SUMMARY OF THE INVENTION It is an object of the present invention to provide a structural form and a construction method of a bridge section using a wire mesh in order to control tensile cracks and sintering heat of a concrete structure.

In order to solve the above-mentioned problems, a composite concrete girder according to the present invention is a concrete girder comprising a flange and a baffle plate disposed perpendicularly to the flange, wherein the concrete girder is formed by curing concrete and forming the flange and the baffle plate. A cast iron core disposed inside the concrete portion; And a wire mesh part disposed at least partially adjacent to the cast steel and disposed inside the concrete part.

In the composite concrete girder, the wire mesh portion may include: a baffle wire mesh, at least a portion of which is disposed on the baffle plate; and a flange wire mesh disposed on the flange and connected to the baffle wire mesh.

In the composite concrete girder, the bimetallic wire mesh includes: a bumper board body wire mesh disposed inside the bumper board; a body wire mesh integrally connected to the bumper board body wire mesh, at least a part of which is different from a plane formed by the bumper board wire mesh; And a strand connecting wire mesh disposed and connected to the flange wire mesh.

In the composite concrete girder, the strand connecting wire mesh and the flange wire mesh may be connected by a binding wire.

In the composite concrete girder, the flange wire mesh may further include a flange inversion wire mesh in which ends of the flange wire mesh extend in an inverted manner.

In the composite concrete girder, the flange wire meshes are respectively disposed at both ends of the stiffener wire mesh, and the flange wire meshes disposed at both ends of the stiffener wire mesh may be substantially the same size.

In the composite concrete girder, the flange wire meshes are respectively disposed at both ends of the stiffener wire mesh, and the flange wire meshes disposed at both ends of the stiffener wire mesh may be different from each other.

In the composite concrete girder, the wire mesh portion may be a steel material or FRP.

According to another aspect of the present invention, there is provided a method of manufacturing a concrete concrete girder comprising a flange and a bumper plate disposed perpendicularly to the flange, the method comprising the steps of: forming a wire mesh comprising two or more segmented wire meshes, A wire mesh subassembly step S2 for assembling the wire mesh subassembly prepared in the wire mesh subassembly step S1, and a step for arranging the assembled wire mesh subassembly, (S4) for installing a wire mesh part in the formwork and installing the assembled wire mesh part in the formwork; and after the completion of the casting preparation step (S4), the concrete And a concrete placing step (S5) of placing a concrete concrete into the concrete concrete pavement.

Wherein the wire mesh portion comprises a bend plate wire mesh at least a portion of which is disposed on the bend plate and a flange wire mesh disposed on the flange and connected to the bend plate wire mesh, The assembling step S2 includes: a step of assembling a bobbin wire mesh (S21) for assembling the bumper plate wire mesh disposed on the bumper plate; a step S23 of assembling a flange wire mesh for assembling the flange wire mesh to the bumper plate wire mesh; . ≪ / RTI >

The composite concrete girder manufacturing method may further include a prestress providing step (S41) of providing a pre-tensioning force to a cast iron disposed in the mold in the casting preparation step (S4).

The composite concrete girder according to the present invention having the above-described structure and the method of manufacturing the same are provided with a wire mesh part made of steel or FRP synthetic fiber on the inner side of the concrete to prevent tensile and shear cracks, And maximize ductility.

In addition, a composite concrete girder and a manufacturing method thereof according to the present invention include a wire mesh for controlling the longitudinal and transverse moments generated in the upper deck and the lower flange, thereby controlling cracks that may occur in the construction and use stages , The construction can be made thinner than the existing one, and an economical cross-section can be presented.

Further, in the composite concrete girder according to the present invention and the method of manufacturing the same, the wire mesh installed on the baffle plate can control the sinusoidal heat of the baffle plate, and the thin cross-section can be constructed.

In addition, the composite concrete girder and the manufacturing method thereof according to the present invention have an advantage that the ductility of the structure can be greatly increased since the coating of the concrete can be prevented by the wire mesh.

While the present invention has been described with reference to exemplary embodiments shown in the drawings, it is to be understood that various modifications and equivalents may be resorted to by those skilled in the art. Accordingly, the true scope of the present invention should be determined by the technical idea of the appended claims.

1 is a diagram showing a crack state of a girder of the prior art.
2 is a perspective view of a composite concrete girder according to an embodiment of the present invention.
3 is a plan view of a type of wire mesh portion of a composite concrete girder according to an embodiment of the present invention.
4 is a schematic enlarged cross-sectional view of a composite concrete girder according to an embodiment of the present invention.
5 is a schematic, partially enlarged cross-sectional view of a composite concrete girder according to a variant of an embodiment of the present invention.
FIG. 6 is a schematic enlarged partial cross-sectional view showing an example of a state in which a composite concrete girder is arranged in a form according to an embodiment of the present invention.
7 to 12 are schematic diagrams showing a manufacturing process of a synthetic concrete girder according to an embodiment of the present invention.

Hereinafter, a composite concrete girder according to the present invention will be described with reference to the drawings.

The composite concrete girder 10 according to an embodiment of the present invention includes flanges 10a and 10c and a baffle plate 10b. The composite concrete girder 10 is implemented as an I-shaped synthetic concrete girder when the flanges 10a and 10c at both ends have the same width as each other. And the flanges 10a and 10c at both ends have the same width, the composite concrete girder 10 is realized as an I-shaped composite concrete girder, and the flanges 10a and 10c at both ends have different widths, The composite concrete girder 10 can be realized as a T-shaped synthetic concrete girder.

The composite concrete girder 10 according to the present invention includes a concrete portion 20, a main iron core 30 and a wire mesh portion 100 to form a flange and a bumper plate which are integrated.

The concrete portion 20 may have a structure in which ultra high performance concrete (UHPC) having high strength and excellent tensile performance is placed and cured in the formwork, but general concrete may be used. Do.

The cast iron rope 30 may be disposed inside the concrete form part 20 through the placement of the concrete part 20. The main reinforcing bars 30 may be arranged in the longitudinal direction of the composite concrete girder 20, that is, in a region corresponding to the flange at the lower end in the drawing, and extend in a direction perpendicular to the ground. The number can be varied according to the design specification.

The composite concrete girder (20) of the present invention includes a wire mesh part (100) unlike a conventional girder. At least a portion of the wire mesh portion 100 is disposed adjacent to the cast iron rope 30 and disposed inside the concrete portion 20.

The wire mesh portion 100 includes a bend plate wire mesh 110 and a flange wire mesh 120. At least a portion of the bend plate wire mesh 110 is disposed on the bump plate 10b and the flange wire mesh 120 is disposed on the flanges 10a and 10c and connected to the bump plate wire mesh 110. [

The stiffener wire mesh 110 and / or the flange wire mesh 120 may be formed of a mesh type steel wire mesh, the shape of which may be a square mesh, a diamond mesh, Various variants are possible. In addition, a variety of choices are possible, such as having the mesh type of the bell-plate wire mesh 110 and the mesh type of the flange wire 120, or having the same mesh type.

The connection of the baffle wire mesh 110 and the flange wire mesh 120 may be via a separate bond line 130. The bundling line 130 may be formed of a steel wire of the same material as the bumper plate wire mesh 110 and the flange wire mesh 120, or may be formed of other different materials such as synthetic resin, Do.

The bumper board wire mesh 110 of the present invention includes a bumper board body wire mesh 111 and a bumper board connecting wire mesh 113. The bumper board wire mesh 111 and the bumper board connecting wire mesh 113 are integrally formed And may be formed in a structure having a different arrangement relationship with each other. That is, the bumper plate body wire mesh 111 is disposed in correspondence with the bumper plate between the upper and lower flanges in the longitudinal direction. At least one side of the bumper plate body wire mesh 111, And is folded in a plane perpendicular to the plane in which the connecting wire mesh 113 is formed. Bonding between the stiffener wire mesh 110 and the flange wire mesh 120 can be accomplished through the bend plate connecting wire mesh 113 of this elongated forming structure.

A plurality of the bend plate wire meshes 110 are arranged in a corresponding area of the bend plate to have an overall symmetrical configuration. The number of the bend plate wire meshes 110 may be varied according to the design specification. However, at least two bend plate wire meshes Is preferable in that it forms the connection support structure of the flange wire mesh 120. [

Meanwhile, the flange wire mesh 120 may have a simple planar structure, but in some cases, the flange wire mesh 120 may further include a flange inversion wire mesh 120c. The flange inversion wire mesh 120c has a structure in which the flange inversion wire mesh 120c is disposed in an inverse extension from the end portion to the opposite end portion. Such a flange inversion wire mesh 120c forms an increase in contact area with concrete to increase the overall size of the synthetic concrete girder It may also increase the strength.

Further, the flange wire mesh 120 may be formed only on one side of the bend plate wire mesh 110, but is preferably disposed on both ends of the same. In addition, when the flange wire mesh 120 is disposed at both ends of the bimetallic wire mesh 110, the flange wire mesh 120 may have substantially the same size as the I-type composite concrete girder, have. In addition, the flange wire mesh 120 at both ends may have different sizes and the flange wire mesh 120 at the upper side may have a larger size. The T-shaped composite concrete girder may be realized.

In the case of forming a T-shaped synthetic concrete girder, the above-described flange inversion wire mesh may be applied in the same manner as described above.

Although the wire mesh portion 100 has been described mainly with respect to the steel material, the wire mesh portion 100 may be partially or wholly formed of a synthetic resin material such as FRP.

Hereinafter, a manufacturing process of a synthetic concrete girder according to an embodiment of the present invention will be described with reference to the drawings.

The method for manufacturing a composite concrete girder according to the present invention comprises the steps of preparing a wire mesh part S1, a wire mesh part assembling step S2, a molding step S3, a placing preparing step S4 and a concrete placing step S5 ).

First, a wire mesh portion preparation step S1 is executed. In the wire mesh portion preparation step S1, two or more segmented wire meshes are formed, for example, the flange wire mesh 120 and the baffle wire mesh (described above) The wire mesh part 100 is prepared. The structure and shape of the wire mesh part 100 are the same as described above.

Then, a wire mesh subassembling step S2 for assembling and connecting the segmented wire meshes is executed. In the wire mesh subassembling step S2, the individualized abdominal wall wire mesh 110 and the flange wire mesh 120 are connected.

More specifically, the wire mesh part 100 assembled in the wire mesh subassembling step S2 may be subjected to the following assembling process. That is, the wire mesh subassembly step S2 may include a step S21 of assembling the baffle plate wire mesh and a step S23 of assembling the flange wire mesh.

In the step of assembling the stiffener wire mesh S21, the stiffener wire mesh is assembled in a region where the stiffener 10b is formed. When a plurality of stiffener wire meshes are arranged, a separate binding spacer or the like May be further equipped.

Then, a flange wire mesh assembly step (S23) is performed. In the flange wire mesh assembly step (S23), the flange wire mesh 120 can be connected to the bumper plate wire mesh 110 by assembling. Bonding between them may take a structure to bind each elongated portion to each other or may include a process such as welding according to circumstances, but may be structured to be connected through separate binding members depending on the case.

In other words, the wire mesh unit prepared in the wire mesh unit preparation step S1 is assembled. In this case, such a connection is made through a connection line 130 connecting the baffle wire mesh 110 and the flange wire mesh 120 .

In the mold setting step S3, the wire mesh part 100, which is assembled in a segmented manner, is installed in the formwork H. An example of the form H is shown in FIGS. 6 and 12, but the form can be modified in various ways according to the design specification for the purpose of explaining the present invention.

Then, in the preparation preparation step S4, the assembled wire mesh part 100 is installed with the cast iron 30 inside the form H.

A wire mesh portion in which the form H is installed and assembled to the mold H, and a structure in which the cast iron rods are individually disposed may be used.

Then, a concrete casting step in which the concrete is placed in the form H is executed. Then, when a predetermined curing process is performed and the form is removed, a composite concrete girder according to the present invention is formed.

Meanwhile, it is possible to further provide a process of imparting a prestress state to improve the durability and performance of the synthetic concrete girder as the case may be.

That is, the putting preparation step S4 may further include a prestress providing step S41, in which the prestressing force may be provided to the cast iron rods 30 disposed inside the form H in the prestress providing step S41 .

10 ... Synthetic concrete girder
20 ... Concrete
30 ... Cast iron rods
100 .. Wire mesh part
110 ... staple board wire mesh part
120 ... flange wire mesh part
130 ... binding line

Claims (11)

A concrete girder comprising a flange and a baffle plate disposed perpendicular to the flange,
A concrete part cured by concrete casting to form the flange and the bumper plate;
A cast iron core disposed inside the concrete portion; And
And a wire mesh portion disposed at least partially adjacent to the cast steel and disposed inside the concrete portion.
The method according to claim 1,
The wire mesh portion includes:
At least a part of which is disposed in the baffle plate,
And a flange wire mesh disposed on the flange and connected to the bend plate wire mesh.
3. The method of claim 2,
The baffle wire mesh comprises:
A bobbin body wire mesh disposed inside the bumper plate,
And a strand connecting wire mesh integrally connected to the strand body wire mesh and at least a part of which is disposed in a plane different from a plane defined by the stranded wire mesh and connected to the flange wire mesh.
The method of claim 3,
Wherein the bumper connecting wire mesh and the flange wire mesh are connected by a connecting line.
3. The method of claim 2,
Wherein the flange wire mesh further comprises a flange inversion wire mesh having an end inverted and extending.
3. The method of claim 2,
Wherein the flange wire mesh is disposed at both ends of the bobbin wire mesh,
Wherein the flange wire meshes disposed at both ends of the stiffener wire mesh are substantially the same size.
3. The method of claim 2,
Wherein the flange wire mesh is disposed at both ends of the bobbin wire mesh,
Wherein the flange wire meshes disposed at both ends of the stiffener wire mesh are different in size from each other.
The method according to claim 1,
Wherein the wire mesh portion is made of steel or FRP.
A composite concrete girder manufacturing method for manufacturing a concrete girder comprising a flange and a baffle plate disposed perpendicularly to the flange,
A wire mesh portion preparation step S1 for preparing a wire mesh portion including two or more segmented wire meshes,
A wire mesh assembling step S2 of assembling the wire mesh part prepared in the wire mesh part preparing step S1,
A mold setting step (S3) for installing a mold in which the assembled wire mesh part is disposed,
(S4) for installing a cast iron wire inside the mold and installing the assembled wire mesh part,
And a concrete placing step (S5) of placing the concrete into the mold after the placing preparation step (S4) is completed.
10. The method of claim 9,
Wherein the wire mesh portion includes a bend plate wire mesh at least a portion of which is disposed on the bend plate and a flange wire mesh disposed on the flange and connected to the bend plate wire mesh,
The wire mesh assembling step (S2) includes:
A step of assembling a bend plate wire mesh (S21) for assembling the bend plate wire mesh disposed on the bend plate,
And a flange wire mesh assembling step (S23) of assembling and connecting the flange wire mesh to the bumper plate wire mesh.
10. The method of claim 9,
And a prestress providing step (S41) for providing a pre-tensioning force to the cast iron bars disposed in the mold in the casting preparation step (S4).

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