KR101850498B1 - Composite part of steel girder and manufacturing method of composite part - Google Patents

Abstract

The present invention relates to a negative moment part of a steel box girder, and a reinforcing method thereof using a steel composite. In a box-type bridge constructed by steel, a girder is reinforced through a steel composite method by installing an assembled type landfill frame and casting concrete at an inner lower portion of the steel box girder, so that the long span can be possible even in the same thickness or reduced thickness. In detail, the present invention includes: a steel box girder formed of a metal and having a box-shaped section; a concrete composite part placed under the neutral axis of an inner cross section of the girder and casted by concrete; and a landfill frame accommodated in the concrete composite part. The steel box girder includes: a lower flange formed of a flat plate; an upper flange formed at a position spaced apart from the lower flange; and a web formed between the lower flange and the upper flange. The concrete composite part is a section for casting concrete into a negative moment part, curing the concrete and performing steel composite work after installing the steel box girder on a bridge. The concrete composite part includes: a casting concrete; and a welding stud coupled within the steel box girder. The landfill frame has a triangular or rectangular cross section, is formed in a truss shape in the longitudinal direction, and has a height adjusting portion at a lower portion of the landfill frame.

Description

{Composite part of steel girder and manufacturing method of composite part}

The present invention relates to a box-type bridge made of a steel material, in which a girder is reinforced by a steel composite method by using an assembled type flame-retardant frame and concrete pouring in the inner lower part of a steel box girder, And the steel composite reinforcing method of the present invention.

Patent Document 001 relates to a steel composite girder structure and a method of constructing a steel composite girder bridge, and more particularly, to a steel composite girder structure and a steel composite girder bridge construction method in which a plurality of steel composite girders are horizontally connected. The steel composite girder structure includes a plurality of steel composite girders arranged in the transverse direction; And a connecting portion provided so as to connect the steel composite girders adjacent to each other among the plurality of steel composite girders.

Patent Document 002 discloses a steel composite girder and a beam in which a steel material and a reinforcing concrete are efficiently combined, and relates to a steel composite girder and a beam in which a steel material and a reinforcing concrete are efficiently combined. In order to prevent cracks from occurring in the slab by integrally joining the slabs and to effectively support the bending moments acting on the steel composite girder and beams, the steel composite girders installed between the steel composite columns are made of steel and reinforcing bars The composite steel is combined with reinforced concrete in the central section where the flexural compressive stress and the shear stress are increased by combining the concrete, and the steel beam installed between the steel composite girders is more than 1/2 of the maximum bending moment. The bending tensile stress and shear stress To provide a steel composite girder and beam with increased structural efficiency and increased stiffness.

Patent Document 003 is an invention relating to a steel composite box girder, which comprises a steel upper flange having a longitudinally bent portion at the center, a steel lower flange spaced apart below the steel upper flange, and both sides of the steel upper flange, A steel box girder connected to the steel flange and having a height greater than the width of the steel flange; And an upper concrete 51 placed on the upper side of the steel box girder. Specifically, the steel composite box girder is formed into a narrow shape having a width smaller than the height of the abdomen of the upper and lower flanges, thereby reducing the amount of steel used, reducing the amount of reinforcement disposed in the longitudinal and transverse directions inside the girder, And the effect of simplifying the manufacturing process.

Patent Literature 004 relates to a prestressed steel composite girder integrated type fastening port, and relates to a prestressed steel composite girder integrated type fastening port, in which a fastening port head of a tension member fixed to a fusing plate is not projected by integrally forming a fastening port on a steel composite girder A lower flange connected to the upper plate, a lower flange connected to the upper plate, and a lower flange connected to the side of the upper plate. A pair of fixing plates installed on the vertical plate so that one side thereof is inserted into contact with the abdomen plate; A pair of side plates connected to the other side of the fixing plate so as to protrude from the fixing plate; And a lower plate connecting the pair of side plates at a lower end of the side plate to each other; The present invention provides a pre-stressed steel composite girder-integrated fastening port.

KR 10-2012-0046479 A (Published on May 10, 2012) KR 10-1204583 B (Registration date November 19, 2012) KR 10-2016-0017881 A (Published on February 17, 2016) KR 10-1581752 B (Registration dated December 24, 2015)

The present invention relates to a box-type bridge made of a steel material, in which a girder is reinforced by a steel composite method by using an assembled type flame-retardant frame and concrete pouring in the inner lower part of a steel box girder, And the steel composite reinforcing method of the present invention.

The present invention relates to a composite girder parent mandrel having a box girder (100) having a box-like cross section and formed of a steel sheet, a lower portion of the concrete box girder ), And a filling frame (300) accommodated in the concrete combining part (200).

In the steel composite girder portion of the present invention, in the steel box girder, the concrete composite portion, and the buried frame as described above, the buried frame 300 is formed in a reinforcing structure and has a triangular or square cross- .

In the steel box girder, the concrete composing part, and the embedding mold of the present invention, the height of the steel box girder is set to a height adjusting part 310 ).

In the steel composite girder part of the present invention, in the steel box girder, the concrete composite part, and the embedding frame proposed above, the embedding frame is formed at both ends in the longitudinal direction, and connects the supporting angles, A reinforcing steel bar 322 formed in a longitudinal direction and formed as a section steel bar; and a reinforcing bars 323 for reinforcing the supporting steel bar and the lower longitudinal steel bars.

In the steel composite girder portion of the present invention, in the steel box girder, the concrete composite portion, and the embedding frame proposed previously, the embedding frame installation position is a position spaced from the inner surface of the lower flange 111 or the inner surface of the lower flange by a predetermined distance As shown in FIG.

The steel composite girder parenting part of the present invention includes a steel box girder, a concrete composite part, and a buried frame, which are previously described, and have a flat plate shape, and a plurality of pouring frame tops are contacted to the lower side.

In the steel composite girder of the present invention, in the steel box girder, the concrete composite portion, and the embedding frame, the steel box girder 100 includes a lower flange 111 formed as a flat plate, And a pair of opposing webs 113 formed between the bottom flange and the top flange.

The steel composite girder part of the present invention is a steel box girder, a concrete composing part, and an embedding frame, which are formed in the upper flange and are formed of a plurality of steel plates, And a tensioning caliper 160 formed of a plurality of steel plates, the number of which is less than or equal to the number of compression grooves.

The manufacturing process of the mandrel part includes a step of manufacturing a steel box girder and a preliminary manufacturing step (S100) of manufacturing a filling frame; a bonding step (S200) of installing a filling frame manufactured in a preliminary manufacturing step inside a steel box girder; (S300) in which the steel box girder is alternately placed at the upper end of the bridge pier after the joining step; and a pouring step (S400) of placing the concrete in the steel box girder after the placing step.

The present invention improves the bending rigidity of the inner lower part of the steel box girder due to the effect of the concrete pouring, thereby reducing the manufacturing cost and the construction cost. The concrete composite part under the steel box girder of the present invention has an effect of reducing compressive stress. The buried frame in the concrete composite part of the present invention has the effect of combining the steel box girder and the concrete.

Since the height of the embedment frame of the present invention is easily adjustable, the height of the embedment frame can be adjusted according to the height of the concrete placement. , Compressive longitudinal ribs, compressed transverse ribs, and the like can be prevented in advance to improve work safety.

Since the embedding frame of the present invention is a reinforcing structure, it is easy to manufacture and the structure can be manufactured at low cost.

Since the concrete box girder concrete section of the present invention can replace a part of the compression stirrups of the lower flange by the buried frame, it is possible to reduce the amount of compression stock, reduce the amount of horizontal stiffeners to be embedded in the concrete, .

FIG. 1 is a conceptual view of a deflection state of a girder according to the presence or absence of a parenthetical part of the present invention. FIG.
FIG. 2 is a conceptual diagram illustrating various aspects of the present invention. FIG.
3 is a perspective view of the embedding frame and height adjuster of the present invention.
4 is a cross-sectional view of the embedding frame and concrete section of the present invention.
Fig. 5 shows various embodiments of the embedment framed steel of the present invention. Fig.
6 is a cross-sectional view of a portion of a parenthetical part when the embedding frame of the present invention is installed on a lower flange;
7 is a cross-sectional view of a portion of a parenthetical part when the embedding frame of the present invention is provided on an extruded lateral rib.
8 is a flow chart of the manufacturing process of the parent mandrel part of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

(Embodiment 1-1) The steel composite girder according to the present invention comprises a steel box girder (100) having a box shape in cross section and formed of a steel plate, a concrete box A composite part 200, and a filling frame 300 accommodated in the concrete composite part.

The girders are supported by alternating and / or piercing. The fulcrums supported by alternating and / or piercing angles form the maximum moment and maximum deformation angle. However, the momentum portion of the present invention increases the stiffness of the fulcrum portion, thereby minimizing the strain angle and achieving the maximum moment reduction. Therefore, it becomes possible to make a long span, and the effect of reducing the manufacturing cost and the construction cost can be obtained. Specifically, the lower part of the inside of the steel box girder belonging to the fulcrum part forms a large crack part. Since the concrete has a high compressive stiffness, it is located at the lower part of the neutral axis inside the steel box girder, thereby reducing the compressive stress and improving the bending rigidity of the steel box girder itself.

Concrete and steel box girders are heterogeneous materials and material separation may occur due to deformation. In order to overcome this, welded studs are welded to the web and bottom flange of steel box girders which are embedded in concrete, and a filling frame is installed on the lower flange or lateral ribs to prevent separation phenomenon by combining with concrete curing.

The concrete composing part 200 includes a welding stud 180 installed on both side webs and a lower flange and a hermetic filling frame 300 installed on the lower flange and the compressive transverse ribs together with the concrete 210 cured in the field Steel composite. Steel box girders and concrete are generally used to improve the bonding strength, but the present invention uses a flushing frame together with a welding stud to increase the strength of the thick concrete. Further, the filling frame is accommodated in the concrete composite portion, and serves as a reference for the height of the concrete pouring, and a pouring foot plate is installed at the top.

(Example 2-1) In Example 1-1, the embedding frame 300 is formed in a reinforcing structure and has a triangular or square cross-section and is formed in a truss shape.

The embedding frame is installed in the longitudinal direction below the inside of the steel box girder. The embankment frame is intended to improve not only the resistance to bending of steel box girders but also the bonding strength of concrete and steel box girders. In order to improve the productivity, the embedding frame is formed by the combination of the plural reinforcing rods and the bent reinforcing rods using the deformed reinforcing bars. The cross-sectional shape is preferably a polygonal shape, and is preferably formed in a triangular or quadrangular shape. And a truss shape in the longitudinal direction.

(Example 3-1) In Example 1-1, a height regulating portion 310 formed at a lower portion of the above-mentioned embedding frame and coupled to inside of a steel box girder is formed.

The thickness of the concrete in the concrete composite portion may be constant or may vary along the length direction. Specifically, the focal point forms a thick concrete thickness, and the farther away from the focal point, the thinner the concrete thickness. Inside the steel box girder concrete is laid up to the top of the filling frame. In order to accommodate the change in the height of the concrete pouring, the height of the pouring frame is provided through the height adjuster. That is, the height of the concrete pouring height can be changed by an artificial adjustment of the height adjuster.

(Example 3-2) In Example 3-1, the height regulating portion includes a height adjusting bolt 311 coupled to a lower flange or the like, a screw bolt screwed to the height adjusting bolt, And a height adjustment nut (312).

A bolt and nut fastening structure was applied to adjust the height of the filling frame. The height adjustment bolts are fixed on the lower flange in the steel box girder, on the transverse ribs, and on the burying frame fixing plate of the diaphragm. The bolt is inserted into the through-hole of the filling frame and the two height-adjusting nuts are screwed to the height-adjusting bolts above and below the supporting angle. Therefore, the embedding frame is fixed by a bolt and nut fastening with a steel box girder, and the installation height can be changed or fixed by rotating the nut. When the thickness of the concrete is thinner than about 500 mm, it is preferable to install the height adjusting bolt for installing the filling frame on the flange below the steel box girder. However, when the thickness of the concrete is thicker than 500 mm, it is preferable to install the height adjusting bolt on the transverse ribs and on the fixing frame attached to the diaphragm.

 (Example 4-1) In Example 3-1, the embedding frame includes a supporting angle (321) formed at both ends in the longitudinal direction, a lower longitudinal reinforcing bar (322) connecting the supporting angles and formed in plural; A supporting steel bar 324 formed in the longitudinal direction and formed of a section steel, and a connection type reinforcement bar 323 for joining the supporting steel bar and the lower longitudinal steel bar.

Burying frame The base structure consists of two bearing angles. The supporting angle may be a steel shape or a metal block. Preferably, the L-shaped steel is provided so as to face the longitudinal direction. Bottom reinforcement is joined between two support angles. The lower longitudinal reinforcing bars may be formed of one or a plurality of reinforcing bars, but it is preferable that two reinforcing bars are provided symmetrically. The connecting reinforcing bars are fabricated by bending in a triangular, rectangular, or tapered shape in the longitudinal direction, one side being joined with the lower longitudinal reinforcing bars, and the other side being joined with the supporting beams. The connecting reinforcing bars are placed facing each other and joined with two lower longitudinal reinforcing bars and one bearing steel so that the cross-sectional shape of the filling frame is triangular or rectangular. The bearing steel is welded to the top of the two connecting bars.

(Example 4-2) In Example 4-1, the bearing steel includes those formed in "C shape ".

(Example 4-3) In Example 4-1, the bearing steel includes those formed in "T shape ".

(Example 4-4) In Example 4-1, the bearing steel includes those formed in an "O-shape ".

(Example 4-5) In Example 4-1, the bearing steel includes those formed in "L-shape ".

(Example 4-6) In Example 4-1, the bearing steel includes those formed in a "box shape ".

The uppermost part of the filling frame forms a bearing steel. The lower part of the support beam is coupled with the connection reinforcing bars, and the upper part of the support beam stably installs the below-mentioned pivot plate to serve as a reference of the height of the concrete pouring. To this end, the shape of the bearing steel is formed in the shape of "U", "T", "O", "L"

 (Example 4-7) In Example 4-1, a lower transverse reinforcing bar 325, which is coupled between the lower longitudinal reinforcing bars and formed in plural, is included.

The present invention joins the lower transverse reinforcement between two lower longitudinal bars. This is to form a stable structure. In particular, to prevent deformation of the lower longitudinal reinforcement when the longitudinal bending deformation of the embedding frame is prevented.

(Examples 4-8) In Example 4-1, an intermediate transverse reinforcing bar 326 for joining the connecting reinforcing bars is included.

One embedding frame installs two connecting reinforcing bars symmetrically. Each connecting reinforcing bar is joined to the intermediate reinforcing bar. This is to improve the deformation resistance of the connecting reinforcing bar to the bending load of the filling frame.

(Embodiment 5-1) In Embodiment 4-1, the embedment frame installation position is provided at a position spaced a certain distance from the inner surface of the lower flange 111 or the inner surface of the lower flange.

For example, when the concrete thickness is less than 500 mm, the installation position of the filling frame is installed on the lower flange 111 of the steel box girder. When the thickness of the concrete is thicker than 500 mm, the compression lateral rib 142 and the filling frame And is mounted on the fixing plate 143. This is judged based on the lateral ribs.

 (Embodiment 6-1) In Embodiment 4-1, a flat footboard 330 is provided and a plurality of flushing frame tops are brought into contact with the lower side.

During the concrete casting process, the operator works inside the steel box girder. Therefore, it is necessary to secure the work space of the operator during the concrete casting process. For this purpose, a floating footrest is installed at the top of the filling frame. The putting footrests are placed on the top of a plurality of embedding frames, and the worker can work on the putting footrests. Since the scaffold is disassembled after the concrete is poured, the scaffold is formed so as not to be fixed to the upper end of the frame.

(Example 7-1) In Example 1-1, the steel box girder 100 includes a lower flange 111 formed as a flat plate, an upper flange 112 formed at a distance from the lower flange, And a pair of opposing webs (113) formed between the lower flange and the upper flange.

The steel box girder of the present invention is formed in a box shape, specifically, an upper and a lower flange are formed, and a web is formed therebetween. Each flange and web is welded. Not only a box shape but also an open form steel girder can be used for an equal purpose.

(Example 7-2) In Example 7-1, a diaphragm 120, which is formed inside the girder and formed in a plurality of spaces, shields a space, and is formed inside the diaphragm 120, (121).

The inside of the steel box girder of the present invention forms a diaphragm. The diaphragm is formed of a steel plate. In the diaphragm, a manhole is formed in which the operator and the inspector can move. Particularly, the diaphragm of the fulcrum where the girder base is installed can be combined with the stiffener and the jack-up stiffener for maintenance.

 (Example 7-3) In Example 7-1, two transverse sections formed between the diaphragm 120 and the diaphragm 120, two vertical plates facing each other, one side in the longitudinal direction of the diaphragm 120 facing each other And a first vertical stiffener 130 formed on the web 113 and having opposite ends coupled to the upper flange 112 and the other end coupled to the lower flange 111.

To improve the bending and torsional stiffness of the steel box girder, a first vertical stiffener is formed in the transverse section inside the girder. The first vertical stiffener is formed at two positions at 1/4 and 3/4 of the distance between the diaphragm and the diaphragm, and connects the upper flange, the lower flange, and the web, and is symmetrically coupled to both the webs.

(Example 7-4) In Example 7-1, a transverse section formed at an intermediate portion between the diaphragm 120 and the diaphragm 120, and a T-shaped transverse transverse rib 141 was attached to the upper flange Shaped lateral ribs 142 are coupled to the lower flange, and a T-shaped compression transverse rib 142 is coupled to the lower flange. Two vertical plates are opposed to each other between the T-shaped transverse ribs, And a vertical stiffener 140.

In order to improve the bending and torsional stiffness of the steel box girder, a rectangular transverse section composed of a tension transverse rib, a compression transverse rib and a second vertical stiffener is formed at a middle position between the diaphragm inner diaphragm and the diaphragm distance. The tensile transverse ribs are T-shaped in cross section and are provided with through holes as many as the number of tensioning ribs described later and are welded to the upper flange. The compressive transverse ribs are T-shaped in cross-sectional shape and are provided with through-holes by the number of compression ribs described later and welded to the lower flange. The second vertical stiffener is formed at a position where the two vertical plates contact the tension transverse ribs and both ends of the compressed transverse ribs and both webs. One longitudinal side of the vertical plate contacts the web and both ends are welded to the tension transverse ribs and the compressive transverse ribs.

(Example 7-5) In the example 7-1, a plate-shaped horizontal stiffener 170 formed in a longitudinal direction of a steel box girder on both side webs in a steel box girder and composed of one or more stages is included .

In order to increase the rigidity of the web plate constituting the steel box girder, the web forms a single-stage or multi-stage horizontal stiffener. Horizontal stiffeners are joined to the web by welding. In the case of uniform cross-section girders, they are arranged at regular intervals and at constant intervals in the case of cross-section girders.

(Examples 7-6) In the example 7-1, a welding stud 180 formed in the lower flange of the inside of the steel box girder, and disposed at regular intervals in the lateral direction and the longitudinal direction, respectively.

Concrete is filled in the box girder of the steel box, and a plurality of welding studs are formed on the both side webs and the lower flange of the steel box girder to increase the coupling force between the concrete and the steel box girder. It is preferable that the welding stud is formed at a place where a large amount of bonding force between the concrete and the steel sheet is required.

(Embodiment 7-7) In Embodiment 7-1, a work hole 191 formed in the upper flange and formed to penetrate is included.

(Examples 7-8) In Examples 7-7, a finishing plate 193 covering the work holes and being easily welded by welding is provided.

The concrete pouring inside the steel box girder of the present invention proceeds after installing the steel box girder. Therefore, the upper flange requires a concrete inlet pipe for concrete pouring, a work tool, and an entry opening for the operator's movement. For this purpose, a work hole is formed in the upper flange. Before the reinforcement and concrete pouring of the bottom plate slab on the upper part of the steel box girder, the work hole is covered with finishing plate and finished by welding.

(Example 8-1) In Example 7-1, a compression stem 150 formed on the lower flange and formed of a plurality of steel plates, formed on the upper flange, formed in plural, And a tensioned longitudinal rib 160 formed of the same material.

Steel Box Girders In order to improve the bending rigidity, the inside of the steel box girder is joined to the flange by a vertical rib formed of a plate material. The steel box girder is subjected to a bending load and the lower part of the neutral axis of the cross section of the steel box girder is compressed. Therefore, to prevent buckling by the compressive force acting on the lower flange and to increase the rigidity of the panel, the compression flange is welded to the compression flange. Also, the upper part of the neutral axis of the cross section of the steel box girder is pulled. Therefore, in order to increase the rigidity of the panel due to the tensile force acting on the upper flange, the tensioning sleeve is welded to the upper flange.

(Example 8-2) In Example 8-1, the number of the compression evaporation ribs is formed to be more than or equal to the number of the tension evaporation ribs.

The bending stresses are generated at the fulcrum of the box girder and the lower portion of the neutral axis of the cross section of the steel box girder is under compressive stress and the upper portion is subjected to tensile stress. Also, the number of the compression ribs attached to the flange is about twice as many as that of the tension ribs to prevent the buckling of the steel plate by the compressive force. The present invention can sufficiently cope with compressive stress even if the number of compression sheaves is reduced by the number of tension sheaves by placing concrete on the lower portion of the neutral axis of the cross section of the steel box girder. This is effective in reducing construction cost through steel reduction.

(Example 9-1) The parent matter manufacturing process according to the present invention comprises the steps of manufacturing a steel box girder and a prefabrication step (S100) for preparing a filling frame; (S300) for placing the steel box girder alternately or at the top of the pier after the joining step; placing the concrete in the steel box girder (S400) after the placing step; ).

(Embodiment 9-2) In Embodiment 9-1, a height adjustment step (S250) of the embedding frame height to adjust the height of the embedding frame after the combining step.

(Embodiment 9-3) In Embodiment 9-1, a step (S350) of setting the placement foot on the top of the filling frame after the above-mentioned seating step is included.

(Embodiment 9-4) In Embodiment 9-1, a separating step (S450) of separating the floating scaffold at the upper end of the embedding frame after the placing step is performed.

100: Steel box girder 111: Lower flange
112: upper flange 113: web
120: diaphragm 121:
130: first vertical stiffener 140: second vertical stiffener
141: Tension transverse ribs 142: Compression transverse ribs
143: Filling frame reinforcing plate 150: Compression vertical rib
160: Tension caliper 170: Horizontal stiffener
180: Welding stud 191: Working hole
193: Finishing plate
200: Concrete composite part 210: Concrete
300: embedding frame 310: height adjusting section
311: height adjusting bolt 312: height adjusting nut
321: Supporting angle 322: Lower longitudinal reinforcement
323: connection type reinforcement bar 324: support beam steel
325: lower transverse reinforcement 326: intermediate transverse reinforcement
330:

Claims (9)

In the steel composite girder part,
A steel box girder 100 formed of a steel plate and having a box shape in cross section;
A concrete mixer 200 located below the steel box girder and made of concrete 210;
A filling frame 300 accommodated in the concrete composite portion;
The steel box girder 100 includes a lower flange 111 formed as a flat plate;
An upper flange 112 formed at a distance from the lower flange;
A web (113) formed between the lower flange and the upper flange;
A height regulating unit 310 formed at a lower portion of the embedding frame and coupled to the inside of the steel box girder,
The supporting frame has supporting angles (321) formed at both ends in the longitudinal direction;
A plurality of lower longitudinal reinforcing bars 322 connecting the supporting angles;
A bearing steel 324 formed in a longitudinal direction and formed of a section steel;
A connecting diaphragm 323 for joining the supporting beam steel and the lower longitudinal steel bar;
The support-type steel is formed in a "T shape ";
A lower transverse reinforcement 325 coupled between the lower longitudinal reinforcing bars,
And a middle transverse reinforcement (326) joining between the connection reinforcing bars.

The method according to claim 1,
Wherein the embedding frame (300) is formed in a reinforcing structure and has a triangular or square cross section and is formed in a truss shape.
delete delete The method according to claim 1,
Wherein the embedment frame installation position is installed at a position spaced apart from the inner surface of the lower flange (111) or the inner surface of the lower flange.
The method according to claim 1,
And a putting step (330) having a flat plate shape and a plurality of upper end portions of the landing frame contacted to the lower side.
delete The method according to claim 1,
A compression stem 150 formed in the lower flange and formed of a plurality of steel plates;
And a tensile caliper (150) formed on the upper flange and formed of a plurality of steel plates.
delete

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