JP2001348997A - Metal girder element and pc girder element using corrugated web steel plate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a metal girder element and a PC girder element capable of having a simple construction, a low construction cost, and of accepting a prestress without being affected by flange and without reducing yield strength. SOLUTION: Flanges 5 are attached to the top and bottom end portions of a corrugated web steel plate 1 at predetermined intervals leaving discontinuous spacings 7 symmetrically between the top and bottom so as to position the projected portions 2 of the corrugated web steel plate 1 inside the discontinuous spacings 7.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a metal girder element and a PC girder element using a corrugated web steel plate used in the fields of civil engineering, construction and the like.

[0002]

[Prior art] Review of seismic design after the Great Hanshin Earthquake,
In response to requests for reduced construction costs and labor savings in construction, etc., studies are being made on bridge structures that are lighter and have less burden on the substructure. Among them, a corrugated web steel plate PC bridge using corrugated steel for the web of girders Has been adopted.

[0003] Corrugated web steel sheet has the property of expanding and contracting like an accordion and not resisting axial force and bending moment.
It has a high shear buckling strength and can be used for PC bridge webs to reduce the weight of the main girder, improve the efficiency of introducing prestress, save labor in construction, and reduce costs associated with these. .

As an example of a conventional bridge using a corrugated web steel sheet, there is an invention described in Japanese Patent Application Laid-Open No. 11-222811. As shown in FIG. 8, the steel composite composite bridge according to the present invention is a precast prestressed concrete slab 3 to be laid on the upper surface of a corrugated web 21.
At every interval of the position of the joint joint 31 of 0, a flange 22 made of a steel plate and provided with a stud dowel 23 on the upper surface is installed, and the upper end of the web 21 is extended between the flanges 22 to a position higher than the flange 22. An upper end portion 24 is provided, and a precast prestressed concrete floor slab 30 is laid in parallel on an upper surface of a steel girder 20 having a reinforcing bar 25 provided on the extended upper end portion 24 so as to be placed on an adjacent flange 22. The stud dowel 23 is positioned at the joint joint 31 to fill the filler from the joint joint 31 of the precast prestressed concrete slab 30.

[0005]

In the composite steel composite bridge constructed as described above, a part of the web 21 is cut and the flange 22 is joined, or a process such as drilling is performed to form the reinforcing bar 25. Due to the complicated structure such as installation, the production is complicated and the increase in production cost is unavoidable. Further, as shown in FIG. 9, the case of adding the prestressing P _3, since the deformation of the plate element to the joint end portion 26 of the web 21 and the flange 22 appears, the shape of the web 21 is no longer retained, the web 21
Might decrease the proof stress.

The present invention has been made to solve the above-mentioned problems, and has a simple structure and a low construction cost.
An object of the present invention is to provide a metal girder element and a PC girder element using a corrugated web steel sheet that can introduce a prestress without being affected by a flange and that does not lower the proof stress.

[0007]

According to the present invention, a metal girder element using a corrugated web steel sheet according to the present invention is vertically symmetrical at predetermined upper and lower ends of the corrugated web steel sheet with a discontinuous portion at a predetermined interval. The flange is attached so that the convex portion of the corrugated web steel plate is located in the portion. Further, in the above metal girder element, flanges were attached such that the convex portions of the corrugated web steel plate in adjacent discontinuous portions were located in opposite directions.

The PC girder element using the corrugated web steel sheet according to the present invention is vertically symmetrical at predetermined upper and lower ends of the corrugated web steel sheet with discontinuities at predetermined intervals, and is provided within the discontinuous part. And a metal girder element with a flange attached so that the convex part is located, concrete floor slabs are provided above and below the metal girder element and integrated to give a prestress. Further, the flanges were attached so that the projections of the corrugated web steel plate in the adjacent discontinuous portions of the PC girder elements were located in opposite directions.

[0009]

[First Embodiment] FIG. 1 is a perspective view of an example of a metal girder element according to a first embodiment of the present invention, FIG. 2 is a plan view thereof, and FIG. 3 is a front view thereof. In FIG. 1, reference numeral 1 denotes a corrugated web steel sheet (hereinafter referred to as a corrugated web) on which convex portions 2 protruding alternately back and forth at substantially equal pitches are formed.
The upper and lower ends are separated by discontinuous portions 7 at a predetermined interval,
A flat flange 5 made of a steel plate is symmetrically joined by welding or the like. Reference numeral 6 denotes a slip stopper, such as a stud dowel, joined to the upper surface (or lower surface) of the flange 5 by welding or the like.

At the time of joining the flange 5 to the corrugated web 1, as shown in FIG.
In the discontinuous portions 7 of the adjacent flanges 5, the intervals are set so as to be alternately located in opposite directions. That is,
The base 8 of the corrugated web 1 and the flange 5 is joined in such a manner that both edges of each flange 5 in the longitudinal direction of the corrugated web 1 are aligned with the corners of the convex portion 2 of the corrugated web 1 to form a metal girder element 10 is constituted.

In the metal girder element 10 according to the present embodiment configured as described above, when a prestress P ₁ is applied as shown in FIG. 4, a compressive force is applied to the discontinuous portion 7 of the flange 5 of the corrugated web 1. Is introduced, the convex portion 2 is deformed in the direction of the arrow, and this portion alternately protrudes in the direction orthogonal to the longitudinal direction of the corrugated web 1 in the opposite direction as shown in FIG. It is narrowed, to absorb the pre-stress P _1.

The deformation of the projection 2 is caused by the corrugated web 1
Since the strain is concentrated on the corner bent portion of the corrugated web 1 which is the base 8 with the flange 5 and the shape of the corrugated web 1 is maintained, the corrugated web 1 maintains its original strength. be able to. Further, since the directions of the protruding portions 2 of the corrugated web 1 in the discontinuous portions 7 of the adjacent flanges 5 are opposite to each other, the protruding directions due to the prestress are alternated, and therefore, as shown in FIG. Web 1
Does not cause any displacement between the flanges 5 even if the flanges shrink.

The metal girder element 10 according to the present embodiment has a simple structure, and therefore, the construction cost is low, and the accordion effect of the corrugated web can be exerted by the prestress without being affected by the flange 5. . Also,
Since the prestress is absorbed by the original deformation of the corrugated web, local deformation is less likely to occur in the corrugated web 1, so that the prestress can be introduced without lowering the proof stress.

Second Embodiment FIG. 6 is a front view of a PC girder element according to a second embodiment of the present invention. In the present embodiment, a concrete floor slab 16 is cast by cast-in-place or the like so as to embed the flanges 5 provided above and below the metal girder element 10 according to the first embodiment. by integrating slab 16 were synthesized, as shown in FIG. 7, it is obtained by building the PC digit element 15 prestressed P _2.

In the PC girder element configured as described above, a prestressing compressive force is introduced into the discontinuous portion 7 of the flange 5, and the corrugated web 1 has its convex portion 2, as described in the first embodiment. Can alternately protrude and shrink in the direction orthogonal to the bridge axis, and prestress can be effectively introduced from the discontinuous portion 7 of the flange 5 to the concrete slab 16. The PC girder element 15 according to the present embodiment has a simple structure, and therefore, the construction cost is low, and the concrete floor slab 16 is effectively prestressed by the accordion effect of the corrugated web 1 without being affected by the flange 5. Can be introduced.

In the above description, the case where a corrugated web having a substantially trapezoidal convex portion 2 is used has been shown. Other cross-sectional shapes may be used.

[0017]

The metal girder element using the corrugated web according to the present invention is characterized in that the upper and lower ends of the corrugated web steel plate are separated from each other by predetermined discontinuous portions, and the convex portions of the corrugated web steel plate are provided in the discontinuous portions. Since the flanges are mounted such that they are located, the structure is simple and the construction cost is low, and the accordion effect of the corrugated web steel sheet can be exerted by prestress without being affected by the flanges. In addition, since the prestress is absorbed by the original deformation of the corrugated web steel sheet, local deformation is unlikely to occur, so that the prestress can be introduced without lowering the proof stress.

In the above-mentioned metal girder element, the flange is mounted so that the convex portions of the corrugated web steel sheet in the adjacent discontinuous portions are located in opposite directions, so that the above-mentioned effects are obtained and the convex portions due to prestress are provided. The protruding directions are alternated, so that even if the corrugated web steel sheet contracts, no deviation occurs between the flanges.

The PC girder element according to the present invention is provided with concrete floor slabs above and below the above-mentioned metal girder element and integrated to apply a prestress thereto, so that the structure is simple and the construction cost is low. The prestress can be effectively introduced into the floor slab by the accordion effect of the corrugated web steel sheet without being affected by the flange.

In the above-mentioned PC girder element, the flange is mounted so that the projections of the corrugated web steel sheet in the adjacent discontinuous portions are located in opposite directions. Even if the steel sheet shrinks, no deviation occurs between the flanges.

[Brief description of the drawings]

FIG. 1 is a perspective view of a metal girder element according to Embodiment 1 of the present invention.

FIG. 2 is a plan view of FIG.

FIG. 3 is a front view of FIG. 1;

FIG. 4 is an operation explanatory diagram of the first embodiment.

FIG. 5 is an operation explanatory view of the first embodiment.

FIG. 6 is a front view of a PC girder element according to the second embodiment of the present invention.

FIG. 7 is an operation explanatory view of the second embodiment.

FIG. 8 is an exploded perspective view of a bridge using a conventional corrugated web steel plate.

FIG. 9 is an operation explanatory view of FIG. 8;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Corrugated web steel plate (corrugated web) 2 Convex part 5 Flange 6 Slip stopper 7 Discontinuous part 8 Base 10 Metal girder element 15 PC girder element 16 Concrete floor slab

Claims (4)

[Claims] 1. A flange is mounted on upper and lower ends of a corrugated web steel plate vertically and symmetrically with a discontinuous portion at a predetermined interval therebetween so that a projection of the corrugated web steel plate is located in the discontinuous portion. A metal girder element using a corrugated web steel sheet. 2. A metal girder element using a corrugated web steel sheet according to claim 1, wherein a flange is mounted such that the projections of the corrugated web steel sheet in adjacent discontinuous portions are located in opposite directions. 3. A metal having a flange attached to upper and lower ends of a corrugated web steel plate vertically and symmetrically with a discontinuous portion at a predetermined interval therebetween so that a convex portion of the corrugated web steel plate is located in the discontinuous portion. A PC girder element using a corrugated web steel sheet, comprising a girder element, and prestressing the metal girder element by providing concrete floor slabs above and below the metal girder element. 4. The PC girder element using a corrugated web steel sheet according to claim 3, wherein a flange is mounted such that the projections of the corrugated web steel sheet in adjacent discontinuous portions are located in opposite directions.