JP2007023714A - Composite floor slab using shape steel, composite floor slab bridge or composite girder bridge and its construction method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a structure of a composite floor slab, a composite floor slab bridge or a composite girder bridge and a construction method using shape steel superior in economic efficiency and construction efficiency, and having high fatigue durability. <P>SOLUTION: A plurality of H shape steels 30 are juxtaposed in advance in the flange direction in a factory so that a flange is vertically positioned, and mutual lower flanges 30b of the adjacent H shape steels are connected by bolt joining or welding so that a corrugated plate or U shape steel projects upward via the corrugated plate or the U shape steel having the height of 1/2 or more of a flange interval of the H shape steel, and mutual vertical stiffening materials of the adjacent H shape steel welded in advance at a predetermined interval are connected via the bolt joining or the welding via a horizontal girder, and are carried up to a construction site thereafter. A plurality of reinforcements 36 are arranged at a predetermined interval in the axial direction of the H shape steel on an upper flange 30a of the H shape steel so as to become a right angle to the axial direction of the H shape steel, and cast-in-place concrete 38 is placed so as to cover these reinforcements. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a composite floor slab using shape steel (a plate structure that is installed on the upper surface of a main girder and forms a road surface), and a synthetic floor slab bridge composed of the synthetic floor slab (an upper surface directly forms a road surface). Bridge structure having both a slab and a floor slab), or a composite girder bridge using the composite floor slab (a bridge structure in which a floor slab installed on the main girder is also used as an upper flange of the main girder), and its construction method About.

'Patent Documents 1 to 3 are known as prior art relating to the present invention.

  As shown in FIG. 17 (corresponding to FIG. 1 of Patent Document 1) and FIG. 18 (corresponding to FIG. 2 of Patent Document 1), the technique of Patent Document 1 is a T-shaped steel 1 having a protrusion 1b on the upper surface of the upper flange upper surface 1a. Are arranged in parallel at a required interval, and each upper horizontal portion of the reinforcing bar 4 formed into a trapezoidal wave shape so as to have a height of about 1/2 to 1/3 of the height of the web 1c of the T-section steel 1 4a is placed perpendicular to each T-shaped steel 1 with projections, and the upper distribution force is perpendicular to each T-shaped steel 1 with projections at a position slightly above the upper surface of the upper flange 1a of each T-shaped steel 1 with projections. After the rebar 3 is arranged, the concrete 6 is placed on-site to the lower horizontal part 4b of the lower distribution reinforcing bar 4, and the tensile side concrete part that does not contribute to strength is made hollow, thereby reducing the weight and cross section. It provides an efficient composite floor slab bridge. In the figure, 5 is a foamed resin body.

  Further, in the technique of Patent Document 2, as shown in FIG. 19 (corresponding to FIG. 1 of Patent Document 2), the bottom plate of the linear steel sheet pile 11 and the main girder member 13 of H-shaped steel or CT-shaped steel are joined and integrated. A steel panel 21 in which a plurality of bridge axial members 14 are joined, and a PC steel material 18 is passed through the web of straight steel sheet piles 15 and side plates 16, and then cast-in-place concrete 20 is placed. Since the rigidity in the direction perpendicular to the axis can be secured, the construction of the cross beam 19 and the work of on-site joining can be eliminated, and the transportation cost can be reduced. In the figure, reference numeral 12 denotes a claw portion of the steel sheet pile 11.

  Further, as shown in FIG. 20 (corresponding to FIG. 1 of Patent Document 3), the technology of Patent Document 3 is a bridge in which the bottom plate of the lower U-shaped steel sheet pile 11A and the main girder member 13 of H-shaped steel are joined and integrated. While integrating a steel floor slab 26 in which a plurality of axial members 14 and upper U-shaped steel sheet piles 11B are combined and widened, and a frame member 17 in which a half U-shaped steel sheet pile 15 'and side plates 16 are joined together. The caster concrete 20 is cast after the cross beam member 19 is joined to the web of the main girder member 13 and the side plate 16 with bolts and the like, and the area required for assembling the steel floor slab is reduced. By adopting a vertical joining method, it is a structure that eliminates the need for steel sheet pile slide pull-in equipment. In the figure, 21 is a mesh streak.

  The synthetic effect of the inner rib H-section steel with ribs attached to the inner surface of the H-section steel is described in Patent Document 4 regarding the H-section steel and the wall body using the H-section steel. Document 1 also confirms that a high synthesis effect with concrete can be obtained. Here, the rib means a protrusion, and in H-shaped steel, a rectangular or triangular steel material is usually attached to the inside of the flange by welding or formed integrally when the H-shaped steel is rolled.

No. 7-39927 Japanese Patent Laid-Open No. 9-221717 JP-A-11-229329 JP 2005-98059 A “Basic bending properties of SC composite underground wall” (The 58th Annual Scientific Lecture, Japan Society of Civil Engineers, V-244, pp. 487-488, September 2003)

  However, the above-mentioned composite floor slab bridge has the following problems.

  That is, in the case of Patent Document 1 using the T-shaped steel 1 having the protrusion 1b on the upper surface of the flange on the main girder, since the upper distribution reinforcing bar 3 is placed in addition to the protrusion height of the flange, The covering thickness of the concrete 6 increases. Moreover, at the time of ultimate bending strength, the protrusion 1b of the upper flange 1a exhibits a wedge action, and the covering concrete is peeled off.

  In the case of Patent Documents 2 and 3, since the integration of the steel main girder and the concrete depends on the adhesion of the steel surface (natural bond) and the displacement restraint by the laterally tightened PC steel, the adhesion increases due to an increase in load. Since the gap between the steel and the concrete is abrupt when it is cut, a stable ultimate strength cannot be obtained.

  In the case of Patent Document 3, since the upper U-shaped steel sheet pile 11B is located at a position close to the neutral axis, it hardly functions as a strength member, and mainly functions as a frame material, and has an uneconomical cross-sectional configuration. Become.

  The present invention has been made to solve the above-mentioned problems, and can consider almost the entire cross section of concrete as an effective cross section of concrete capable of resisting a positive bending moment acting on a composite floor slab bridge. The construction of a composite floor slab, a composite floor slab bridge or a composite girder bridge using shape steel, and its construction method, which has good workability, and exhibits high fatigue durability due to its behavior as a plate until reaching its final state. The purpose is to provide.

  In the present invention, a lightweight heavy filler (for example, foamed urethane, polystyrene foam, etc.) having a rectangular or trapezoidal cross-section whose height is half or more of the H-shaped steel flange interval, and the lightweight filler are convex upward. The steel plates that are joined (for example, bonded) and the flanges adjacent to each other in the direction perpendicular to the axial direction of the H-shaped steel of the flange so that the flanges are positioned vertically, A plurality of H-section steels connected (for example, by bolting or welding) and an upper flange of the H-section steel at a predetermined interval in the axial direction of the H-section steel so as to be perpendicular to the axial direction of the H-section steel. The above-mentioned problem is solved by a composite floor slab using shape steel, which is provided with a plurality of rebars installed and concrete placed so as to cover them.

  The present invention also includes a corrugated sheet or U-shaped steel having a height that is at least half of the flange interval of the H-shaped steel, and a direction perpendicular to the axial direction of the H-shaped steel of the flange so that the flange is positioned vertically. A plurality of H-section steels, which are connected to each other so that the lower flanges of adjacent H-section steels are protruded upward through the corrugated sheets or U-section steel, On the upper flange of the H-shaped steel, a plurality of reinforcing bars installed at predetermined intervals in the axial direction of the H-shaped steel so as to be perpendicular to the axial direction of the H-shaped steel, and so as to cover these The above-mentioned problems are solved by a synthetic slab using a shape steel, characterized in that it is provided with concrete.

  In addition, vertical stiffeners of adjacent H-shaped steels joined (eg, welded) at a predetermined interval (eg, in a factory in advance) are connected to each other via a cross beam (eg, by bolting or welding).

  Further, the H-shaped steel is an H-shaped steel having protrusions on the inner surface. Here, protrusions such as ribs can be attached to either or both of the flange of the H-shaped steel and the web.

  The height of the protrusions is preferably 2 mm or more and 50 mm or less, the width is preferably 1 to 5 times the height, and the distance between the protrusions is preferably 4 times or less the width.

  The present invention also provides a strip-like shape having a plurality of holes in the axial direction of the H-shaped steel on the web cutting surface of the T-shaped sectional steel obtained by cutting the H-shaped steel web in the axial direction of the H-shaped steel. It is characterized in that a plurality of T-shaped cross-section members, which are welded steel plates to extend the web height, are welded to a bottom steel plate that also serves as a formwork, and concrete is cast so as to cover the T-shaped steel cross-section members. To provide a synthetic floor slab.

  The present invention also provides a composite floor slab bridge comprising the above-described synthetic floor slab.

  The present invention also provides a composite girder bridge comprising the above-described composite floor slab.

  In the present invention, a plurality of H-section steels are installed in the flange direction in advance so that the flanges are positioned vertically, and the lower flanges of adjacent H-section steels are spaced apart from each other by the height of the H-section steel. Adjacent H-shapes that are connected by bolting or welding so that the corrugated sheet or U-shaped steel is convex upward through one-half or more corrugated sheets or U-shaped steel, and previously welded at predetermined intervals in the factory Steel vertical stiffeners are connected to each other by bolting or welding via cross beams, and then transported to the construction site. At the construction site, the axial direction of the H-shaped steel is placed on the upper flange of the H-shaped steel. A composite floor slab using section steel, characterized in that a plurality of rebars are installed at predetermined intervals in the axial direction of the H-section steel so as to form a right angle, and cast-in-place concrete is cast to cover them. For construction methods of composite floor slab bridges or composite girder bridges Ri is obtained by solving the above problems.

  According to the present invention, when a positive bending moment is applied to the composite slab, the portion other than the vicinity of the H-shaped steel in the concrete cross section is also the lower corrugated sheet or U-shaped steel, the reinforcing bar and the cross beam, and the H-shaped steel. Since this part receives the restraining force of 2 axes from this, and this part is located above 1/2 of the height of H-section steel, most of this part becomes a compression area | region. As a result, almost the entire cross section of the concrete becomes an effective cross section, and high strength is obtained with respect to a positive bending moment. H-shaped steel with protrusions on the inner surface of the H-shaped steel (the dimensions of the protrusions are preferably 2 mm or more and 50 mm or less in height, and the width is preferably 1 to 5 times the height. 3), it is desirable that the width be less than 4 times the width, and a triaxial compression state that is constrained also in the axial direction of the H-section steel is formed, and higher bending strength is obtained. In addition, compared with the case of obtaining a composite effect by installing a stopper such as a stud, it is not necessary to consider the fatigue durability of the stopper welded portion, so an economical design is possible. In addition, since the steel members are composed of small pieces, if they are all assembled on site, they are highly transportable and can be installed in a limited work space because heavy equipment used on site may be small. .

  Furthermore, since it has a simple structure in which the stopper and the reinforcing bar do not converge, the workability is also good.

  The corrugated plate includes a corrugated plate and a liner plate. Further, the corrugated plate material includes concrete.

  In addition, the above describes that the present invention is effective for a positive bending moment, but a structure that is also effective for a negative bending moment by reversing the structure of the present invention upside down. It becomes.

  The effect of this invention is shown below.

(1) When a positive bending moment is applied to the composite floor slab, the portion other than the vicinity of the H-shaped steel in the concrete section is also biaxial from the lower corrugated sheet or U-shaped steel, the reinforcing bar and the cross beam, and the H-shaped steel. Since this part is located above half of the height of the H-section steel, most of this part becomes the compression region. As a result, almost the entire cross section of the concrete becomes an effective cross section, and high strength is obtained with respect to a positive bending moment.

(2) H-shaped steel with protrusions on the inner surface of the H-shaped steel (the dimensions of the protrusions are preferably 2 mm or more and 50 mm or less in height, and the width is preferably 1 to 5 times the height. Is preferably 4 times or less of the width), a triaxial compression state that is constrained also in the axial direction of the H-section steel is formed, and higher bending strength can be obtained.

(3) Moreover, compared with the case where a slip stopper such as a stud is provided to obtain a composite effect, it is not necessary to consider the fatigue durability of the slip welded portion, so that an economical design is possible. In addition, since the steel members are composed of small pieces, if they are all assembled on site, they are highly transportable, and the heavy equipment used on site can be small, so construction can be performed within a limited work space. .

(4) Furthermore, since it has a simple structure in which the stopper and the reinforcing bar do not converge, the workability is also good.

(5) Since the section steel is covered with concrete, it is not necessary to consider the buckling phenomenon of the section steel, and since the painted area is small, a more economical design is possible.

(6) Since unnecessary lower concrete where tensile force is generated is lost, it is light in weight so that it is possible to make a long span. In addition, concrete cracks are less likely to occur.

  Embodiments of the present invention will be described below with reference to the drawings.

  FIG. 1 shows a bridge structure having an embodiment of the present invention, wherein D is a floor slab to which the present invention is applied, P is a bridge pier, B is a cross beam, F is a footing, and G is the ground.

  FIG. 2 is a composite floor slab bridge according to the first embodiment using a section steel according to the present invention. In the first embodiment, a plurality of H-section steels 30 are perpendicular to the axial direction (longitudinal direction) of the H-section steel of the flange so that the flanges 30a and 30b are positioned vertically (referred to as the flange direction). In parallel, the lower flanges 30b of adjacent H-shaped steels have a rectangular or trapezoidal cross-section lightweight filler 34 whose height is ½ or more of the H-shaped steel flange interval. A plurality of rebars 36 are connected to the H-shaped steel 30 on the upper flange 30a of the H-shaped steel 30 so as to be perpendicular to the axial direction of the H-shaped steel 30 after being joined by bolted bonding or welding through the bonded steel plates 32. These are installed at predetermined intervals in the axial direction, and concrete 38 is cast so as to cover them, and the steel materials constituting the composite slab bridge D are integrated. The arrow a in the figure is the stress direction.

  As the lightweight filler 34, lightweight concrete can be used in addition to urethane foam and polystyrene.

  In the second embodiment of the present invention, as shown in FIG. 3, vertical stiffeners 40 of adjacent H-section steels 30 previously welded in a factory at predetermined intervals are connected to each other by bolting or welding via a cross beam 42. It is what I did. Since other points are the same as those of the first embodiment, description thereof is omitted.

  In the third embodiment of the present invention, instead of connecting the lower flanges 30b of the adjacent H-shaped steels 30 via the steel plate 32, the height is 1/2 of the flange interval of the H-shaped steel 30 as shown in FIG. The corrugated sheet or U-shaped steel 50 is connected by bolting or welding so that the corrugated sheet or U-shaped steel 50 is convex upward.

  Further, in the fourth embodiment of the present invention, as shown in FIG. 5, the vertical stiffener 40 and the cross beam 42 similar to those of the second embodiment shown in FIG. 3 are added to the third embodiment shown in FIG. It is provided.

  As the H-section steel 30, for example, an inner rib H-section steel 31 having protrusions such as ribs 31c on the inner surface as shown in FIG. 6 can be used. The construction procedure of the composite slab or the composite slab bridge of the fifth embodiment of the present invention using the inner rib H-section steel 31 is shown in FIGS.

  At the time of construction, as shown in FIG. 7, a plurality of inner rib H-sections 31 are pre-installed at the factory in the flange direction so that the flanges 31a and 31b are positioned vertically, and adjacent inner ribs as shown in FIG. The corrugated sheet or U-shaped steel 50 is located above the lower flanges 31b of the H-shaped steel 31 with the corrugated sheet or U-shaped steel 50 having a height that is at least half the flange interval of the inner rib H-shaped steel 31. Adjacent inner rib H-section steel 31 connected by bolting or welding so as to be convex and welded in advance at predetermined intervals in the factory (the inner rib 31c has a height of 2 mm to 50 mm in height and a high width. The vertical stiffeners 40 are preferably 1 to 5 times the height, and the interval between the inner ribs is preferably 4 times the width or less), as shown in FIG. , Connect by bolting or weldingThereafter, the steel sheet is transported to the construction site. At the construction site, as shown in FIG. 10, a plurality of reinforcing bars are placed on the upper flange 31a of the inner rib H-section steel 31 so as to be perpendicular to the axial direction of the inner rib H-section steel 31. 36 are installed at predetermined intervals in the axial direction of the inner rib H-shaped steel 31, and cast-in-place concrete 38 is placed so as to cover them as shown in FIG.

  FIG. 12 shows a sixth embodiment of the present invention in which an inner rib H-section steel 31 is used instead of the normal H-section steel 30 in the third embodiment shown in FIG.

  FIG. 13 shows a seventh embodiment in which a steel plate 32 and a lightweight filler 34 are added to the sixth embodiment.

  FIG. 14 shows an eighth embodiment in which a vertical stiffener 40 and a cross beam 42 are added to the seventh embodiment.

  FIG. 15 shows a ninth embodiment in which the U-shaped steel 50 of the sixth embodiment shown in FIG. 12 is changed to a corrugated plate 52 and a vertical stiffener 40 and a cross beam 42 are added.

  FIG. 16 shows a tenth embodiment corresponding to claim 7, and in the case where the length of the support is long or the load applied is large, the rigidity of the inner rib H-section steel alone is high in strength, deformation limitation, and design. This is an example when it is difficult. A T-shape in which a strip steel plate 62 having a plurality of holes in the longitudinal direction is welded to a web cutting surface 60a of a T-shaped cross-section steel 60 obtained by cutting a web of inner rib H-section steel in the longitudinal direction to extend the web height. After the cross-section member is joined to the bottom steel plate 64 by welding, the cross-section member is installed on site, and concrete 38 is placed so as to cover the T-shaped cross-section member. At this time, in order to reduce the dead load, a light filler 34 is installed on a part of the concrete tension side before placing the concrete to minimize the concrete cross section. In the figure, 36 is a reinforcing bar.

  In addition, the kind of protrusion is not limited to a rib.

  Although the specifications of the bridge according to the present embodiment vary depending on the type and scale of the bridge, in the fifth embodiment shown in FIGS. 7 to 11, the corrugated plate 52 is used instead of the U-shaped steel 50. An example of dimensions in the configuration of the used example is as follows.

  The cross-sectional dimension of the inner rib H-section steel 31 is 600 mm × 300 mm × 12 mm × 25 mm, and the length is 12 m. The dimensions of the inner rib 31d are 2 mm or more and 50 mm or less in height, and the width is 1 to 5 times the height. The interval between the inner ribs 31d is not more than four times the width. The interval with the inner rib H-section steel 31 provided side by side is 600 mm. The size of the vertical stiffener 40 is 600 mm × 150 mm × 12 mm, and the installation interval is 5 m in the bridge axis direction. The dimension of the cross beam (I-shaped cross section) 42 for connecting the adjacent inner rib H-shaped steel is 250 mm × 200 mm × 12 mm × 9 mm, and the installation interval is 5 m in the bridge axis direction. The corrugated plate 52 is an 8 mm thick steel plate having a height of 300 mm. The reinforcing bar 36 sets D25 at an interval of 250 mm.

The perspective view which shows the bridge structure which comprises embodiment of this invention The perspective view which shows the composite floor slab bridge of 1st Embodiment using the shape steel by this invention. The perspective view which similarly shows the composite floor slab bridge of 2nd Embodiment The perspective view which similarly shows the synthetic floor slab of 3rd Embodiment The perspective view which similarly shows the synthetic floor slab of 4th Embodiment (A) Front view and (b) Perspective view showing the structure of the inner rib H-section steel used in the composite floor slab bridge of the fifth embodiment. The perspective view which similarly shows the first construction procedure of 5th Embodiment The perspective view which similarly shows the next construction procedure of 5th Embodiment The perspective view which similarly shows the next construction procedure of 5th Embodiment The perspective view which similarly shows the next construction procedure of 5th Embodiment The perspective view which similarly shows the next construction procedure of 5th Embodiment The perspective view which similarly shows the composite floor slab bridge of 6th Embodiment The perspective view which similarly shows the composite floor slab bridge of 7th Embodiment The perspective view which similarly shows the composite floor slab bridge of 8th Embodiment The perspective view which similarly shows the composite floor slab bridge of 9th Embodiment The perspective view which similarly shows the composite floor slab bridge of 10th Embodiment The perspective view which shows the principal part of the composite floor slab bridge using the conventional shape steel described in patent document 1 Similarly, a cross-sectional view along line AA in FIG. The perspective view which shows the principal part of the composite floor slab bridge using the conventional shape steel described in patent document 2 The perspective view which shows the principal part of the composite floor slab bridge using the conventional shape steel described in patent document 3

Explanation of symbols

D ... Synthetic floor slab using shape steel (bridge)
B ... Beam P ... Pier F ... Footing G ... Ground a ... Stress direction 30 ... H section steel 30a, 31a ... Upper flange 30b, 31b ... Lower flange 31 ... Inner rib H section steel 31c ... Web 31d ... Inner rib 32 ... Steel plate 34 ... Non-shrink material 36 ... Reinforcement 38 ... Concrete 40 ... Vertical stiffener 42 ... Cross girder 50 ... U-shaped steel 52 ... Corrugated sheet 60 ... T-shaped cross-section steel 60a ... Web cut surface 62 ... Strip steel plate 64 ... Bottom steel plate

Claims (12)

A lightweight filler with a rectangular or trapezoidal cross-section that is at least half the height of the H-shaped steel flange;
Steel plates joined so that the lightweight filler is convex upward;
A plurality of H-section steels that are provided side by side in the direction perpendicular to the axial direction of the H-section steel of the flange so that the flanges are positioned above and below, and the lower flanges of adjacent H-section steels are connected via the steel plate;
A plurality of reinforcing bars installed at predetermined intervals on the upper flange of the H-shaped steel so as to be perpendicular to the axial direction of the H-shaped steel;
Concrete placed to cover these,
A composite floor slab using section steel, characterized by comprising: Corrugated sheet or U-shaped steel whose height is half or more of the H-shaped steel flange interval;
The flanges are arranged in the direction perpendicular to the axial direction of the H-shaped steel in the flange direction so that the flanges are positioned above and below, and the lower flanges of adjacent H-shaped steels, A plurality of H-sections connected so that the U-section is convex upward;
A plurality of reinforcing bars installed at predetermined intervals in the axial direction of the H-shaped steel so as to be perpendicular to the axial direction of the H-shaped steel on the upper flange of the H-shaped steel;
Concrete placed to cover these,
A composite floor slab using section steel, characterized by comprising:   The composite floor slab using a section steel according to claim 1 or 2, wherein vertical stiffeners of adjacent H-section steel joined at a predetermined interval are connected via a cross beam.   The composite floor slab using a section steel according to claim 1 or 2, wherein an interval between adjacent H-section steels is equal to or less than a flange interval of the H-section steel.   The composite floor slab using a section steel according to any one of claims 1 to 4, wherein the H section steel is an H section steel having a protrusion on an inner surface.   The composition using the structural steel according to claim 5, wherein the height of the protrusion is 2 mm or more and 50 mm or less, the width is 1 to 5 times the height, and the interval between the protrusions is 4 times or less the width. Floor slab. A strip-like shape having a plurality of holes in the axial direction of the H-shaped steel on the cut surface of the T-shaped cross-sectional steel obtained by cutting the H-shaped steel web according to claim 5 or 6 in the axial direction of the H-shaped steel. Welding a plurality of T-shaped cross-section members that are welded to a steel plate and extending the web height to a bottom steel plate that also serves as a formwork;
A composite floor slab characterized in that concrete is cast so as to cover the T-shaped steel cross-section member.   A synthetic floor slab bridge comprising the synthetic floor slab according to claim 1.   A composite girder bridge comprising the composite floor slab according to claim 1. Pre-installed multiple H-shaped steel bars in the factory so that the flanges are positioned above and below,
Bolts such that the corrugated sheet or U-shaped steel protrudes upward through the corrugated sheet or U-shaped steel whose height is ½ or more of the flange interval of the H-shaped steel. Connected by welding or welding,
In addition, the vertical stiffeners of adjacent H-section steel welded in advance at a predetermined interval in the factory are connected to each other by a bolt joint or welding via a cross beam.
Then transport to the construction site,
At the construction site, on the upper flange of the H-shaped steel, a plurality of reinforcing bars are installed at predetermined intervals in the direction of the H-shaped steel so as to be perpendicular to the axial direction of the H-shaped steel,
A method for constructing a composite slab using shape steel, wherein cast-in-place concrete is cast so as to cover these. Pre-installed multiple H-shaped steel bars in the factory so that the flanges are positioned above and below,
Bolts such that the corrugated sheet or U-shaped steel protrudes upward through the corrugated sheet or U-shaped steel whose height is ½ or more of the flange interval of the H-shaped steel. Connected by welding or welding,
In addition, the vertical stiffeners of adjacent H-section steel welded in advance at a predetermined interval in the factory are connected to each other by a bolt joint or welding via a cross beam.
Then transport to the construction site,
At the construction site, on the upper flange of the H-shaped steel, a plurality of reinforcing bars are installed at predetermined intervals in the axial direction of the H-shaped steel so as to be perpendicular to the axial direction of the H-shaped steel,
A method for constructing a composite slab bridge using shaped steel, wherein cast-in-place concrete is cast so as to cover these. Pre-installed multiple H-shaped steel bars in the factory so that the flanges are positioned above and below,
Bolts such that the corrugated sheet or U-shaped steel protrudes upward through the corrugated sheet or U-shaped steel whose height is ½ or more of the flange interval of the H-shaped steel. Connected by welding or welding,
In addition, the vertical stiffeners of adjacent H-section steel welded in advance at a predetermined interval in the factory are connected to each other by a bolt joint or welding via a cross beam.
Then transport to the construction site,
At the construction site, on the upper flange of the H-shaped steel, a plurality of reinforcing bars are installed at predetermined intervals in the axial direction of the H-shaped steel so as to be perpendicular to the axial direction of the H-shaped steel,
A method for constructing a composite girder bridge using shaped steel, wherein cast-in-place concrete is cast so as to cover these.

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