JPH0791813B2 - How to build a synthetic slab bridge - Google Patents

Description

TECHNICAL FIELD The present invention relates to a method for constructing a synthetic slab bridge.

"Prior Art" As shown in FIGS. 5 and 6, the present applicant arranges CT section steels 21 having projections 22a on the surface of a flange 22 in parallel at required equal intervals, and the CT section steels with respective projections. The bottom steel plate 24 is welded between the lower end faces of the webs 23 of 21 and the upper distribution reinforcing bars 25 are provided at a position slightly higher than the flange 22 of each CT-shaped steel 21 with protrusions, at a position orthogonal to each CT-shaped steel 21 with protrusions. Arranged, and placing concrete 26 in the so-called parallel open-section steel box girder from the upper surface of the bottom steel plate 24 to a position slightly above the upper distribution reinforcing bar 25, for example, constructing a composite slab bridge such as a road bridge. Already filed (Japanese Patent Laid-Open No. 58-58
-33611 reference).

[Problems to be Solved by the Invention] The CT-section steel with protrusions is a rolled H-section steel having protrusions on the upper and lower flange surfaces, which is half-cut at the center line in the longitudinal direction of the web. The dimensions of the attached CT section steel are determined in accordance with the JIS standard for general H section steel, and the maximum dimensions are 459 mm in height, 303 mm in flange width, 19 mm in web thickness, and 37 mm in flange thickness. Since the second moment of area is 36,800 cm ⁴ , the applicable span length of the current composite deck slab is restricted to 24 m or less.

The present invention has developed a method for constructing a composite slab bridge that solves the disadvantages of the conventional composite slab bridge using the CT-section steel with protrusions.

[Means for Solving the Problems] The gist of the method for constructing a composite deck slab according to the present invention is that an H-shaped steel web having projections on the upper and lower flange surfaces is formed along a corrugated line in its longitudinal direction. Of the corrugated web in the CT section steel with protrusions on the flange surface formed by cutting into two equal parts is welded to one side end surface of the corrugated web bottom end surface along the longitudinal entire length in the longitudinal direction. The CT shaped steels with projections having web height supplementing strip steel plates are arranged in parallel at required equal intervals, and the bottom steel plate is welded across the lower end faces of the web height supplementing strip steel plates in the above-mentioned projection CT strip steels, A parallel open-section steel box girder is formed, and expansive concrete is placed in the parallel open-section steel box girder.

[Operation] As described above, the height of the CT section steel having projections on the flange surface formed by cutting the web of H-section steel having projections on the upper and lower flange surfaces in half along the corrugated line in the longitudinal direction. Is
350 more than the height of conventional 459 mm height CT section steel with protrusions
mm is increased to 809 mm, and further, the one side end face of the web height supplemental strip steel plate of the required plate width is welded over the entire length in the longitudinal direction of the corrugated bottom end face of the corrugated web in the above-mentioned protrusion with the web height. , The CT section steels with projections having this web height supplementing strip steel plate are arranged in parallel at the required equal intervals, and the bottom is spanned between the lower end faces of the web height supplementing strip steel sheet in each of the above projections CT section steels. Welding steel plates to form parallel open-section steel box girders, placing expansive concrete in the parallel open-section steel box girders, and constructing a composite floor slab bridge, thereby maximizing the application of the composite floor slab bridge. It is possible to extend the span length to 38m or more.

Moreover, the expansive concrete placed in the parallel open-section steel box girder is uniformly wound around the entire parallel open-section steel box girder through the cutouts of the corrugated web in the CT section steel with protrusions, and the expansive concrete is poured. Dispersibility is improved.

[Example] Next, an example of a method for constructing a composite slab bridge according to the present invention will be described below with reference to the drawings.

First, as shown in FIG. 1, protrusions are formed on the surfaces of the upper and lower flanges 2.
The web 3 of the H-section steel 1 having 2a is cut in half in the longitudinal direction thereof along, for example, a trapezoidal corrugated line (i), and from one H-section steel 1 with protrusions, as shown in FIG. 2 has a projection 12a on the surface of and a trapezoidal corrugated web 13
Manufactured a set of CT shaped steel 11, and in the same way, CT with the required number of protrusions
Shaped steel 11 is manufactured.

Then, in order to further increase the web height of the CT section steel 11 with protrusions, as shown in FIGS. 3 and 4, the CT section steel 11 with protrusions 11
Of the trapezoidal corrugated web 13 over the entire length in the longitudinal direction of the bottom surface of the corrugated bottom, one side end face of the web height supplementing strip steel plate 17 having a required strip width is welded, and the CT type with projection having the web height supplementing strip steel plate 17 is formed. Steels 11 are arranged in parallel at required equal intervals, and a bottom steel plate 14 is welded across the lower end faces of the strip steel plates 17 for supplementing the web height in each of these projections with CT projections, and each projection with CT projections.
At a position slightly higher than the flange 12 of 11, the upper distribution reinforcing bar 15 is arranged orthogonally to the CT section steel 11 with each protrusion, from the upper surface of the bottom steel plate 14 to a position slightly above the upper distribution reinforcing bar 15. Expansive concrete 16 is placed in the parallel open-section steel box girder to construct a composite slab bridge.

In addition, as shown in FIGS. 3 and 4, outside the upper distribution reinforcing bar 15, if necessary, between the CT section steels 11 with projections, and perpendicularly to the upper distribution reinforcing bar 15. Disposing rebar 18 and / or trapezoidal corrugated web in CT section 11 with each protrusion
Approximately 1/2 of the total height of 13 and the web height supplement strip 17
It is optional to dispose the lower distribution reinforcing bar 19 at a required interval in the longitudinal direction of the portion.

Further, in the embodiment shown in FIG. 3 and FIG. 4, the expansive concrete 16 is placed in the entire parallel open-section steel box girder. From a position slightly lower than approximately half of the total height of the trapezoidal corrugated web 13 and the web height supplemental strip steel plate 17 to a position slightly above the upper distribution reinforcing bar 15 in the parallel open-section steel box girder. A composite deck slab may be constructed so that it is placed only on the compression area side and the tension area side in the parallel open-section steel box girder is hollow, or a foamed resin material is placed in the hollow area on the tension area side. It may be filled to build a synthetic deck bridge.

[Advantages of the Invention] As described above, according to the present invention, a web of H-section steel having projections on the upper and lower flange surfaces is cut into two halves along the corrugated line in the longitudinal direction. The height of the CT-section steel with protrusions is 809 mm, which is 350 mm higher than the height of the conventional maximum-size CT-section steel with protrusions, which is 809 mm. Along the entire length in the direction, one side end face of the strip steel plate for supplementing the required web width is welded to further increase the web height. The steel plates are arranged in parallel at intervals and welded to the bottom steel plate across the lower end faces of the strip steel plates for supplementing the web height of the above-mentioned CT section steels to form parallel open-section steel box girders. Placing expansive concrete inside to build a composite slab bridge And makes it possible to increase the maximum applicable span length of the composite floor slab bridge above 38m.

Moreover, the expansive concrete placed in the parallel open-section steel box girder is uniformly wound around the entire parallel open-section steel box girder through the cutouts of the corrugated web in the CT section steel with protrusions, and the expansive concrete is poured. Dispersibility is improved.

[Brief description of drawings]

FIG. 1 is a perspective view of a H-section steel with protrusions for producing a CT-section steel with protrusions used in the method for constructing a composite deck slab according to the present invention, and FIG. Fig. 3 is an exploded perspective view showing an example of manufacturing a CT-shaped steel with protrusions, Fig. 3 is a cross-sectional view of a composite slab bridge showing an example of the method of the present invention, and Fig. 4 is a line AA in Fig. 3. A sectional view, FIG. 5 is a transverse sectional view of a conventional composite floor slab bridge, and FIG. 6 is a sectional view taken along line AA of FIG. Explanation of symbols 11 …… CT shaped steel with protrusions, 12 …… Flange 12a …… Protrusions, 13 …… Trapezoidal corrugated web 14 …… Bottom steel plate, 15 …… Upper distribution reinforcing bar 16 …… Expanded concrete, 17 …… Web Steel strip for height supplement 18 …… Reinforcing bar, 19 …… Lower distribution reinforcing bar

Claims (2)

[Claims] 1. A corrugated web of a CT section steel having projections on a flange surface obtained by cutting an H-section steel web having projections on upper and lower flange surfaces in half along a corrugated line in a longitudinal direction thereof. The bottom end surface of the corrugated part is welded to one end surface of the strip steel plate for supplementing the web height of the required strip width over the entire length in the longitudinal direction, and the CT section steels with protrusions having the strip steel strip for supplementing the web height are arranged in parallel at required intervals. Then, the bottom steel plate is welded between the lower end surfaces of the strip steel plates for supplementing the web height in the above-mentioned CT-section steel with projections to form a parallel open-section steel box girder, and expanded concrete in the parallel open-section steel box girder. A method for constructing a composite slab bridge, which is characterized by placing. 2. The method for constructing a composite deck slab according to claim 1, wherein the expansive concrete is cast only on the compression region side in the parallel open-section steel box girder.