JP3632760B2 - Corrugated steel web and PC deck bridges - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
TECHNICAL FIELD The present invention relates to a joint structure in a PC bridge using corrugated steel plates for webs, which increases the resistance to bending moment in the direction perpendicular to the bridge axis while ensuring the integrity of the corrugated steel plates and the upper and lower concrete slabs. It is.
[0002]
[Prior art and problems to be solved by the invention]
Upper concrete slab and the lower concrete slab, and is configured corrugated steel web PC bridge from the web of corrugated steel connecting both deck, in FIG. 5 as a displacement preventing the corrugated steel and concrete for the horizontal shear force of the bridge axis As shown in the figure, a method of welding a stud gibber to a flange plate welded to the end face of the corrugated steel plate on the floor slab side is used. Since the design is performed on the premise of maintaining a complete composite structure, the shear force that the stud gibber should bear tends to increase.
[0003]
In order to secure the resistance to the shearing force between the flange plate and the concrete when using the stud gibber, it is necessary to increase the number of stud gibels in order to increase the adhesion area of the stud diver to the concrete, In order to secure the surroundings and adhesion of concrete, there is a limit to the number of flange plates that can be protruded from the corrugated steel plate, so it is necessary to increase the width and thickness of the flange plate to satisfy both conditions. In some cases, the design of the corrugated steel sheet itself needs to be changed, for example, it is necessary to enlarge the dimensions of the corrugated steel sheet itself.
[0004]
In response to this problem, the applicant welded a perforated steel plate having a large number of holes instead of a stud diver to the flange plate, and used the shear strength of the concrete to obtain a shear resistance between the flange plate and the floor slab concrete. A method for securing the force has been proposed (Japanese Patent Laid-Open No. 2000-355906).
[0005]
In this method, as shown in FIG. 7 , the concrete wraps around the hole in the perforated steel plate, so that the horizontal shearing force acting between the concrete and the flange plate acts in the direction of the bridge axis. And the bearing pressure between the inner peripheral surface of the concrete passing through the hole, and the shear strength of the concrete located in the hole in two cross sections on the same plane as both surfaces of the perforated steel plate As a result of the resistance to the shear strength of the core portion of the concrete having a cross-sectional area corresponding to the diameter of the hole being added to the shear resistance, there is an advantage that a greater shear resistance can be expected than when stud studs are provided.
[0006]
However, the position of the cross section of the shear strength exerted by the concrete in the hole of the perforated steel sheet is determined by the thickness of the perforated steel sheet, and the distance between both surfaces of the perforated steel sheet is such that the shear strength of the concrete at that position forms a couple. Therefore, the bending moment in the direction perpendicular to the bridge axis acting on the joint between the corrugated steel plate and the concrete slab cannot be resisted as shown in FIG.
[0007]
Although there is a method of welding an angle diver as shown in FIG. 6 in place of the stud gibber, there is a problem that the amount of welding is large and initial irregularities such as residual stress of the flange plate due to an increase in welding extension become large. In addition, since the angle diver cannot exert the resistance force in the direction perpendicular to the bridge axis, it cannot resist the bending moment in the direction perpendicular to the bridge axis.
[0008]
The present invention proposes a joint structure that can resist the bending moment in the direction perpendicular to the bridge axis that acts on the joint between the corrugated steel sheet and the concrete floor slab.
[0009]
[Means for Solving the Problems]
The concrete side of the flange plate that is welded to the end surface of the concrete slab side of the corrugated steel in the present invention, corrugated steel by parallel webs plate having a through hole formed at intervals in the bridge axis direction Hashijiku perpendicular By welding to the outside across the entire width of the steel plate, a couple is formed by the shear resistance generated by the concrete located in the through holes of each web plate and acts on the joint between the corrugated steel plate and the concrete floor slab Ensure the ability to resist bending moments perpendicular to the bridge axis.
[0010]
The concrete located in the through hole of the web plate exhibits shear resistance in two cross sections on the same plane as both surfaces of each web plate, but in the direction perpendicular to the bridge axis acting on the upper and lower ends of the corrugated steel sheet. With respect to the bending moment, the concrete in the through-holes of each web plate exerts a resistance force in opposite directions to form a moment of couple and resist the bending moment.
[0011]
The magnitude of the shear resistance generated by the concrete for each web plate is the sum of the shear strength in two cross sections located on the same plane as both sides of the web plate. The magnitude of the moment of the couple is determined by the distance between the parallel web plates, and increases as the web plates are separated.
[0012]
The addition Rukoto to penetrate the reinforcing bar into the through hole of the web plate, even after exceeding the shear strength of the concrete to remain rebar is engaged with the through hole, to continue to exert a resistive force to the reinforcing bar, the flange plate and the toughness against bending moment at the junction between the concrete Ru improved.
[0013]
In Rukoto is inserted reinforcing bars into the through hole of the web plate, although rebar size of shear strength of the concrete is eroded, since shear strength of rebar is added to the shear resistance of the concrete in the through hole of the web plate, bending The moment of the couple that resists the moment increases.
[0014]
In particular, the size Kusuru it than the diameter through hole of the reinforcing bar of the web plate, ullage rebar size of Shear Strength of concrete substantially eliminated, as such shear resistance sum of shear strength and shear strength of the reinforcing bars of the concrete It will resist the bending moment.
[0015]
In the present invention, since the bending moment in the direction perpendicular to the bridge axis is resisted by the moment of the couple due to the shear strength of the concrete in the through hole, it is sufficient that at least two web plates are integrated with the flange plate.
[0016]
DETAILED DESCRIPTION OF THE INVENTION
As shown in FIG. 1, the present invention relates to a PC bridge composed of an upper concrete floor slab 1 and a lower concrete floor slab 2 and a corrugated steel plate 3 of a web connecting both concrete floor slabs 1 and 2, and a concrete floor of the corrugated steel plate 3 The web plates 5 and 5 having through holes 5a formed on the concrete side of the flange plate 4 welded to the end faces of the plates 1 and 2 are aligned in a direction perpendicular to the bridge axis and integrated.
[0017]
PC Bridge to bridge axis direction of the bending moment due to dead load and live load, the upper concrete slab 1 and the lower concrete slab 2 to resist in pairs, corrugated steel 3 or corrugated steel as shown in FIG. 4, 3 and web concrete 6, the upper end of the corrugated steel plate 3 is joined to the upper concrete floor slab 1, and the lower end is joined to the lower concrete floor slab 2.
[0018]
As shown in FIGS. 3 and 4 , the PC bridge web gradually increases from the central part of the support to the fulcrum side or near the fulcrum. In particular, FIG. 4 uses a corrugated steel plate 3 having a constant length over the entire length of the span in order to simplify the production of the corrugated steel plate 3 and the joining with the lower concrete floor slab 2. The case where it comprises only the corrugated steel plate 3 and the web near the fulcrum is constituted by the corrugated steel plate 3 and the web concrete 6 below it is shown.
[0019]
As shown in FIG. 1 showing the cross section of the PC bridge, the flange plate 4 has a width that can accommodate the entire width of the corrugated steel plate 3 and is welded to the upper and lower ends of the corrugated steel plate 3. The web plates 5 and 5 are welded to the lower surface of 4 respectively. The flange plate 4 and the web plates 5 and 5 at the upper end of the corrugated steel plate 3 are embedded in the upper concrete floor slab 1, and the flange plate 4 and the web plates 5 and 5 at the lower end are embedded in the concrete of the lower concrete floor slab 2. The web plate 5 may be a striped steel plate.
[0020]
In FIG. 2, the flange plate 4 and the web plates 5 and 5 are continuous in the bridge axis direction, but may be intermittently arranged.
[0021]
Through holes 5a are formed in the web plates 5 and 5 at intervals in the bridge axis direction. In FIG. 2, in order to resist the horizontal shear force in the bridge axis direction and the bending moment in the direction perpendicular to the bridge axis acting between the flange plate 4 and the concrete by the shear strength of the concrete and the shear strength of the reinforcing bar 7, each through hole 5a is used. Reinforcing bars 7 are inserted into the concrete of the upper concrete floor slab 1 or the lower concrete floor slab 2. In this case, it is not necessary to insert the reinforcing bars 7 through all the through holes 5a, and the shape of the through holes 5a is not limited to a circle.
[0022]
When the horizontal shear force acting on the bridge axis acting between the flange plate 4 and the concrete and the bending moment in the direction perpendicular to the bridge axis are resisted only by the shear strength of the concrete passing through the through hole 5a, the reinforcing bar 7 is placed in the through hole 5a. Although it is not necessary to make it penetrate, the through-hole 5a is given a size of about several tens of millimeters to several tens of millimeters at which concrete can exhibit a shear strength.
[0023]
On which is inserted the reinforcing bars 7 into the through-hole 5a, the influence of loss of shear strength of the cross-section integral of concrete corresponding to the diameter of the reinforcing bars 7 so as to exert a shear strength of the concrete in the through-hole 5a is shown in FIG. 2 The through hole 5a is formed to be larger than the diameter of the reinforcing bar 7 to the extent that there is not.
[0024]
【The invention's effect】
On the concrete side of the flange plate welded to the end surface of the corrugated steel plate on the concrete floor slab side, the web plates with through holes formed at intervals in the bridge axis direction are arranged in parallel in the direction perpendicular to the bridge axis. Bending in the direction perpendicular to the bridge axis acting on the joint between the corrugated steel plate and the concrete slab in order to form a couple of shear strength in the two cross sections on the same plane as both sides of the web plate. The ability to resist the moment can be ensured.
[0025]
By inserting the reinforcing bar through the through hole of the web plate, the shearing strength of the reinforcing bar is added to the shearing strength of the concrete, so the moment of the couple that resists the bending moment increases.
[0026]
Since the reinforcing bar penetrates the through hole of the web plate, the reinforcing bar keeps engaging with the through hole even after exceeding the shear strength of the concrete, and the resistance plate continues to exert resistance. Toughness against bending moment at the part is improved.
[0027]
In addition, by making the through hole of the web plate larger than the diameter of the reinforcing bar, the reduction in the shear strength of the concrete is substantially eliminated, so the sum of the shear strength of the concrete and the shear strength of the reinforcing bar resists the bending moment. It can be expected as shear resistance.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view showing a configuration of a corrugated steel web PC bridge.
FIG. 2 is a perspective view showing a relationship between a corrugated steel plate, a flange plate, and a web plate in a case where a concrete shear strength and a reinforcing bar shear strength are exhibited in a through hole of the web plate.
FIG. 3 is an elevational view showing the appearance of a corrugated steel web PC bridge when the web is composed only of corrugated steel.
FIG. 4 is an elevation view showing the appearance of a corrugated steel web PC bridge when the web is composed of corrugated steel and web concrete.
FIG. 5 is a perspective view showing a conventional joint when a stud gibber is welded to a flange plate.
FIG. 6 is a perspective view showing a conventional joint when an angledivel is welded to a flange plate.
FIG. 7 is a perspective view showing a conventional joint when a perforated steel plate is welded to a flange plate.
[Explanation of symbols]
1 …… Upper concrete floor slab, 2 …… Lower concrete floor slab, 3 …… Corrugated steel plate, 4 …… Flange plate, 5 …… Web plate, 5a …… Through hole, 6 …… Web concrete, 7 …… Rebar .

Claims (1)

An upper concrete slab and the lower concrete slab, with the PC bridge composed of corrugated steel web connecting the two concrete slabs, the flange plate is welded to the end surface of the concrete slab side of corrugated steel, concrete flange plate on the side, welded web plate penetrations holes are formed at intervals in the bridge axis direction, the diameter of the through hole in the two cross-section on both sides the same surface of the web plate of the concrete located in the through-hole In the joint structure in which the shear strength of the core portion of the concrete having a cross-sectional area corresponding to is added to resist the horizontal shear force in the bridge axis direction acting between the concrete and the flange plate, the flange plate against, welding the web plate on the outside across the entire width of the corrugated steel by parallel bridge axis perpendicular The Rukoto, so as to resist bending moments of bridge axis perpendicular direction acting on the junction of the corrugated steel and the concrete slab, rebar is inserted into the through hole of the web plate, the diameter of the through hole, through to case of resistance only by shear strength of concrete through the hole, to the extent there is no loss of shear strength the cross-sectional diameter of the integral of the corresponding concrete of the reinforcing bar, corrugated steel web is formed larger than a diameter of the reinforcing bar Joint structure of corrugated steel plate and concrete slab in PC bridge.

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