KR100729370B1 - Composite beam for girder - Google Patents

Abstract

A steel-concrete composite girder is provided to have no necessity for the maintenance of a concrete member by excluding formwork and bar arrangement work for concrete such as RC beams or PSC beams for the existing construction and to secure interlayer height or clearance to the maximum by securing sufficient span length against low clearance. Disclosed is a steel-concrete composite girder(100) formed by filling concrete in box-shaped steel and installed on two columns or piers/abutments(600), which contains outer steel provided with an empty space block-outed on the lower part of a girder by forming hollow penetrations(200) connected horizontally on a web of the composite girder and separated by web columns, and inner concrete(130) filled in the outer steel except the hollow penetration and restricted by the outer steel to secure the effective strength of the composite girder. Hereon a wire tube(400) and a duct(500) are installed to penetrate the hollow penetrations not to install any obstacle on the lower part of the composite girder, an inner reinforcement member(300) including a brace or a spacer is inserted to the hollow penetration, and a steel compression plate(140) is buried under the inner concrete and manufactured to have effective section force to resist the compression stress by external force added on the composite girder.

Description

Composite girder {COMPOSITE BEAM FOR GIRDER}

1A, 1B and 1C show a conventional beam and composite girder in cross-sectional form.

2A, 2B, 2C, and 2D show examples of the assembly installation diagram and the composite girder of the external steel of the present invention.

2E, 2F, 2G and 2H are modifications of FIG. 2D according to the shape of the lower flange of the composite girder.

Figure 3a is another embodiment of a composite girder of the present invention.

3B, 3C, 3D and 3E are modified examples of the shape of the lower flange of the composite girder according to FIG. 3A.

4A and 4B illustrate a state in which the composite girder of the present invention according to FIG. 2B is installed in a pillar or a bridge undercarriage.

<Explanation of symbols for main parts of the drawings>

100: composite girder 110: outer steel sheet

111: upper flange 112: abdomen

113: lower flange 120: hollow through plate

130: inner concrete 140: compressed steel sheet

150: abdominal column 200: hollow through

300: inner reinforcing material 400: wire pipe

500: duct 600: column / bridge substructure

The present invention relates to a composite girder. More specifically, the present invention relates to a composite girder in which steel and concrete, which are installed as a girder on a beam or a civil bridge, installed between upper surfaces of pillars in a building.

In the case of a reinforced concrete beam (10, Reinforced Concrete Beam, RC beam) or prestressed concrete girder (20, PSC beam) as shown in Figure 1a and 1b used as a conventional building beam or bridge girders, Is used in large quantities, inevitably involves the installation and dismantling of the reinforcement and formwork of the reinforcing bars (11, 21),

As a result, a lot of manpower and time must be put in place, and the degradation of concrete and cracked reinforcement due to the action of the load and the environment is inevitable, which makes it difficult to maintain and shorten the service life. There was a problem that it was difficult to construct with this large span.

Furthermore, the RC beam 10 and the PSC beam 20 do not act as a structural cross section that bears the stress in the girder section around the neutral axis in supporting tensile and compressive stresses generated in the beam cross section due to the loading. There was a problem of being inefficient in supporting a load.

In order to compensate for the shortcomings of the RC beam and the PSC beam, as shown in FIG. 1C, a composite beam 30 having a formwork reinforcement 31 surrounded on the outside of the RC girder formed therein has been developed.

However, the composite beam 30 is simply a type surrounding the steel (reinforcement) outside the RC beam in which the reinforcing bar 32 is reinforced, so that the concrete inside does not resist the tension, and thus the self-weight is increased by using unnecessary tension-side concrete. It was pointed out that the reinforcement is required for internal tension side reinforcement, so that it is not suitable for supporting a large upper load as the girders between the long legs.

In addition, when it is necessary to install the ducts and conduits for ventilation inside the building for composite beams, RC beams, and PSC beams, the ceiling height between the bottom plate and the bottom plate is inevitably limited by hanging the beams under the beam. There is a need to secure efficient ceiling heights.

An object of the present invention is to provide a composite girder that does not require the maintenance of the concrete member because there is no need for formwork, reinforcement for concrete, such as existing RC beam or PSC beam for existing construction.

Another object of the present invention is to provide a composite girder capable of sufficiently securing the height between the low girder height compared to the low girder height in bridge girders.

The present invention to achieve the above technical problem,

In the composite girder 100 is filled with concrete in the box-shaped steel,

An outer steel 110 having a hollow space blocked out from the bottom of the girder by forming a hollow through part 200 which is laterally communicated between both ends; And an inner concrete 130 filled inside the outer steel 110 except for the hollow through part 200.

The hollow through part 200 is formed in a plurality of divided by the abdominal column 150 formed between the hollow through part.

In the composite girder 100 of the present invention, the upper flange 111 and the inner concrete 130, which are steel materials, are synthesized so as to support the compressive stress against the load.

By forming a hollow through portion 200 in the lower portion of the abdomen 112 (WEB) to be able to exclude concrete vulnerable to tensile stress, the hollow through portion 200 can be penetrated through the installation ducts, etc. Usability was improved according to

In the case of lower lead, the lower flange 113, which is a steel material, can sufficiently resist tensile stress due to the load, and in particular, the lower flange 113 can be formed in various types of I-type, tube, and circular tube forms to provide more effective loads. Resistance was made possible.

In addition, the composite girder 100 having a rectangular cross section can be provided in consideration of the reduction of the I-shaped cross section or the steel and the increase of its own weight.

Hereinafter, the synthesis girder 100 according to the present invention will be described in detail with reference to the embodiment shown in the drawings.

Figure 2a is an assembled view of the outer steel 110 constituting the composite girder 100 according to the present invention, Figures 2b, 2c and 2d is a completed state of the composite girder according to the upper surface,

2E to 2H are examples of the composite girder 100 according to the shape of the lower flange 113,

3A illustrates another embodiment of a compound girder.

3B to 3E are examples of the composite girder 100 according to the shape of the lower flange 113 based on FIG. 3A.

4A and 4B show an example of installation of a compound girder.

External steel 110 of the present invention is as shown in Figure 2a

Lower flange 113;

The upper surface of the lower flange 113 protrudes upwards and is installed to face each other, so that the inner abdominal space is formed, and the hollow through part plates 121, 122, and 123 are formed below the inner abdominal space so that the hollow through part 200 is formed. ; And

It may be configured to include; the upper flange 111.

Basically, since the external steel 110 serves as a concrete formwork, the concrete 130 is filled and synthesized inside, and is designed as a structural member to prevent additional reinforcement from being reinforced. To make a fundamental structural difference

The batch production at the factory is advantageous for quality control.

In addition, the concrete 130 by the external steel 110 may have the effect of being constrained to be able to have a more effective strength of the composite girder 100.

The lower flange 113,

2A and 3A, but the steel sheet having a predetermined width is shown in a state extending in the longitudinal direction, the width and length can be changed, it is preferable to be formed at least about the upper flange width.

The lower flange 113 has a function to ensure that the composite girder 100 of the present invention is stably supported on the ground or column top surface and to effectively resist the tensile stress to the load, Figures 2e to 2h Or it may be configured in various forms such as 3b to 3e.

That is, the lower flange 113 structurally resists the tensile stress against the load, and the lower flange made of steel and the abdomen formed with a hollow through portion to exclude the concrete as described below to resist the tensile stress,

In essence, it has a function to prevent cracking in concrete that is susceptible to tensile stress.

The abdomen 112 is protruded vertically upwards on the upper surface of the lower flange 113 to be spaced apart from each other so as to form an abdominal inner space, it is produced using two steel sheets.

The abdomen 112 cuts both sides thereof into a predetermined shape as shown in FIG. 2A and 3B, and installs both side plates 121 and 122 by welding to the cut sides, and the upper plate 123 is formed on the top surfaces of the side plates 121 and 122. By also forming by welding, so that the hollow through-hole 200 of the present invention as shown in Figure 2b.

Accordingly, the side plates 121 and 122 and the upper plate 123 are referred to as hollow through plate 120 in the sense of forming the hollow through part 200.

The hollow through part 200 serves as a transverse passage through which the conduit tube 500 and / or the ventilation duct 400 penetrates as shown in FIGS. 4A and 4B.

That is, the conduit 500 and / or the ventilation duct 400 is conventionally installed by hanging the wire under the girder / beam, and thus there is a problem that the use of floors is unreasonable since the ceiling distance is reduced by the space occupied by the wire. In the case of the present invention, it is installed to penetrate the hollow through part 200 formed in the composite girder abdomen, and thus becomes very efficient in using the interlayer height.

Since only a duct or the like may not always be inserted into the hollow through part 200, the inner reinforcing member 300 including the bracing material or the spacer may be further installed therein as shown in FIGS. 4A and 4B.

The hollow through part 400 may be formed in various shapes to occupy a predetermined space in one space as one body, but to be formed spaced apart from each other naturally the abdominal column 150 between the hollow through part 400 ) Is preferably formed so as to be divided into a plurality by the abdominal column.

The number, separation distance, size of space, shape, etc. of the hollow through parts 200 may be designed in an optimal state in consideration of the use, construction, and manufacturing cost of the composite girder.

The inner concrete 130 is filled in the abdominal inner space formed by the abdomen 112.

At this time, in the case of the abdominal column 150 may be to be filled with the inner concrete 300, it may be formed as a hollow portion instead of the inner concrete.

To this end, the upper plate 124 may be formed on the upper surface of the abdominal column 150. In addition, the upper plate 124 may be installed to fill the abdominal column fillers of concrete and other materials such as urethane and epoxy resin, and to form the internal reinforcement material 300 as shown in FIGS. 2A, 3A, 4A, and 4B. It may be.

The abdomen 112 inside the concrete 130 is filled to be synthesized, but the hollow through-hole 200 is formed at the bottom to form a natural form of the blotting out a kind of bleeding out of the concrete vulnerable to tensile stress is excluded In addition to being able to play a role so that the conduit, ducts and the like has a passage forming function that can be penetrated in the transverse direction.

The upper flange 113 is formed by bending the upper end of the abdomen 112 to the outside, and both ends are bent inward to form the upper central opening S1 as shown in FIG. Only a portion of the upper surface of the can be opened.

The upper central opening S1 may serve as a space for placing the inner concrete 130 and a space for allowing the compressed steel plate 140 to be buried in the upper side of the inner concrete 300.

The compressed steel plate 140 is to be made of a member having a more efficient cross-sectional force by resisting the compressive stress due to the external force acting on the composite girder.

The compressed steel plate 140 may be installed in the longitudinal direction in the form of an integral plate 141, but may be installed as a divided steel plate 142 for ease of transportation and installation.

Eventually, the outer steel 110 has a function as a formwork for the inner concrete 130, but is combined with the inner concrete 130 to function as a structural member capable of integrally resisting the inner concrete against the external load.

Due to this function, there is an advantage in that the fatigue stiffness is increased while the vibration and sagging of the synthetic girder are reduced, and thus, the external steel of the present invention may be referred to as an external formwork or an external reinforcement.

Although not shown on the inner surface of the outer steel 110, a plurality of studs are installed by welding or the like to increase the synthetic action with the inner concrete.

In addition, a plurality of studs are also attached to the upper surface of the upper flange 111 of the outer steel 110 for coupling with the bottom plate concrete.

Figure 2c shows in particular that the entire outer surface of the outer steel 110 of the present invention can be manufactured in an open state.

That is, the upper flange 111 is bent to prevent the upper central opening S1 from being formed so that the upper surface of the outer steel 110 is maintained in a completely open state.

Figure 2d shows in particular that the outer surface of the outer steel 110 of the present invention can be manufactured in a closed state.

That is, the lower flange 113, the abdomen 112 and the upper flange 111 is to be formed in a closed box shape. As a result, the upper surface of the outer steel is closed, thereby forming a through hole for placing the inner concrete.

2E to 2H illustrate that the lower flange 113 may be configured in a shape other than a plate shape in FIG. 2C.

In the case of FIG. 2E, the lower flange 113 may be configured in the form of an I-type or H-type beam, and the height may be adjusted to have a predetermined height according to the design of the composite girder. This form can be said to be able to effectively respond to the tensile stress in the lower edge of the composite girder.

In the case of FIGS. 2F and 2G, in particular, the lower flange 113 may be configured in the form of a square tube. In the case of FIG. 2F, the lower flange 113 may be configured in the form of a square tube. It is shown that it can be configured in the form of a flat rectangular tube. When the lower flange 113 is configured in the form of such a tube, it is possible to effectively cope with the tensile stress more effectively in the lower edge of the composite girder, and in particular, it is possible to have the effect of further enhancing the stiffness.

In the case of Figure 2h, as shown that the lower flange 113 can be configured in the form of a circular tube may have the same technical effect produced in the form of a square tube basically.

In addition, the upper flange 111 of the composite girder 100, as shown in Figure 3a, so that both ends are bent inward without bending the upper end of the abdomen 112 to the outside in the state where the upper surface of the outer steel 110 formed through holes It is manufactured to be closed to show that the cross-sectional shape of the composite girder 100 as a whole can be produced in a rectangular shape.

Although not shown, the upper surface of the composite girder, as shown in Figure 2b and 2c may be partially opened by the upper central opening (S1) is formed, it may be to open the whole.

As described above, when the cross-sectional shape of the composite girder 100 is made in a rectangular shape as a whole, it is shown in Figure 3b to 3e showing the various shapes according to the lower flange 113.

That is, in the case of Figure 3b shows that the lower flange 113 may be configured in the form of I-type or H-shaped beam

In the case of Figures 3c and 3d, in particular, it shows that the lower flange 113 can be configured in the form of a square tube, in the case of Figure 3c has been shown that it can be configured in a square tube shape, in the case of Figure 3d It is shown that it can be configured in the form of a flat rectangular tube, in the case of Figure 3e, it shows that the lower flange 113 can be configured in the form of a circular tube.

In the composite girder 100 by removing the upper flange of a kind of haunch shape to form only the abdomen, by reducing the amount of steel occupied by the upper flange of the haunch type and the corresponding inner concrete, it is unnecessary according to the design. While it is possible to eliminate the increase in the weight of the composite girder, it is possible to reduce the amount of expensive steel sheet used.

As a result, the cross-sectional shape of the composite girder of the present invention is introduced in the form of I-shaped, rectangular cross section, in addition to various forms such as circular cross section is not excluded.

4A and 4B show a state in which the composite girder 100 according to FIGS. 2D and 3A is mounted on the upper surface of the piers / shifts 600 which are both pillars or bridge substructures. In other words,

It can be seen that the conduit pipe 400 is installed through the hollow through part 200 formed in the abdomen 112 of the synthetic girder 100, and it can be seen that the duct 500 is installed through the synthesis. It can be seen that no obstacles are installed in the lower part of the girder.

In addition, it can be seen that the hollow through part 200 may be placed in an empty state, and the inner reinforcement material 300, which is a bracing material, may be inserted and installed.

According to the present invention, the outer side is composed of steel and the inner side of which is filled with inner concrete composite girders on the compression side of the upper side of the neutral shaft, the compressive steel plate bears the compressive force according to the structural characteristics, the tension member located under the neutral shaft bears the tensile force By acting as a composite girder that can maximize the advantages of each component such as concrete, steel, and tension material, and offset the load caused by the self-weight generated during the manufacture of external steel by tensioning the tension material installed in the lower part of the composite girder step by step. In the case of making it possible, the composite girders between the long sections can be installed even with the same section size.

In addition, compared to steel box girders made of steel only, the concrete is filled with less noise, and vibration and welding amount are less, resulting in excellent fatigue performance, high rigidity, low risk of local buckling, no need for reinforcement, and no corrosion. Is low.

Since the inner concrete is wrapped in the outer steel, there is no need for reinforcement in the inner concrete, no need for maintenance, such as cracking, and facility pipes and conduits including ducts are formed to penetrate the abdomen of the composite girder to maximize the use of building floors. And it is possible to manufacture and construct a composite girder for construction or civil engineering, especially bridges, which is very economical.

As described above, the present invention is capable of long span at low mold height by supplementing weaknesses of existing girder and utilizing its strengths, and is economical girder type which is advantageous in terms of life cycle cost as well as initial construction cost and low maintenance cost. Not only the advantages but also the beautiful appearance make it aesthetically advantageous form of girders.

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. Those skilled in the art of the present invention 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 (9)

In the composite girder that is filled with concrete in the box-shaped steel, An outer steel having a hollow space blocked out from the bottom of the girder by forming a hollow through portion that is laterally communicated between both ends; And inner concrete filling the inside of the outer steel except for the hollow through portion, wherein the reinforcing bar is not disposed. The composite girder according to claim 1, wherein the hollow penetrating portion is formed in plural numbers by being divided by an abdominal column formed between the hollow penetrating portions. According to claim 2, The outer steel is to be formed in the overall shape of the I-shaped cross-section box or rectangular cross-sectional shape, Lower flange; An abdominal inner space formed protruding upward from the upper surface of the lower flange so as to face each other, and having a hollow through plate formed below the inner abdominal space such that a hollow through portion is formed; And And an upper flange bent so that the upper inner space is formed in the longitudinal direction from the abdominal plate material. According to claim 3, wherein the upper flange upper surface Open top surface; A partially open upper surface formed by bending an upper end of the abdomen inwardly to form an upper central opening; And Shear surface closed upper surface is formed concrete filling hole; Synthetic girder, characterized in that any one of. The bottom flange of claim 3 or 4, wherein the lower flange is at least I-beam; Square tube; And Round tube; Synthetic girder, characterized in that formed in any one of. The composite girder according to any one of claims 1 to 4, wherein a compressed steel sheet is further embedded in the upper flange in the longitudinal direction. The composite girder according to any one of claims 1 to 4, wherein the hollow penetrating portion is further provided with a transverse through member including a building internal pipe. The method according to any one of claims 2 to 4, wherein the interior of the abdominal column formed between the through portion is filled with an empty space or the abdominal column filler including the inner concrete, but to form the empty space Synthetic girder, characterized in that the upper plate is further formed on the top of the abdominal column so that the abdominal column is closed. The composite girder according to claim 8, further comprising an inner stiffener including a bracing member or a spacer in the hollow through portion or the abdominal pillar portion in which the transverse through member is not provided.

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