JP2016223129A - Steel girder reinforcement structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a steel girder reinforcement structure which can suitably reinforce steel girders roughly having a H-shape cross section.SOLUTION: A steel girder reinforcement structure 100 comprises a belt-like member 10, which is arranged to bridge a pair of steel girders 1, each of which roughly has a H-shape cross section, and contacts with the bottom face of each lower flange 1b, and one end part 10a of which is connected to an upper flange 1a of one steel girder 1 while the other end part 10b being connected to an upper flange 1a of the other steel girder 1. Tensile force given in the belt-like member 10 reacts in a direction, in which the upper flanges of the pair of steel girders 1 move away from each other. Thus, a swinging movement of webs 1c of the pair of steel girders 1 to tilt to each other of the pair of steel girders was suppressed, enabling reinforcement of the steel girders 1.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a steel girder reinforcing structure suitable for reinforcing a steel girder having a substantially H-shaped cross section.

When a railway runs on a viaduct, repeated loads are applied to the bridge girder. When the H-section steel is used for the bridge girder, the H-section steel may be deformed in a twisting direction due to the repeated load.
For example, when the floor slab 3 is installed on the H-section steel 1 and there is a rail (loading point) inside the H-section steel 1 that makes a pair, as shown in FIG. The web 1c of the H-section steel 1 swings in the direction perpendicular to the bridge axis due to a load such that the center side of the belt 3 is bent downward, and fatigue cracks are generated due to out-of-plane deformation accompanying the swing. Sometimes.
In order to suppress the out-of-plane deformation of the web and suppress the occurrence and progression of fatigue cracks, reinforcing materials may be reinforced by welding on both sides of the web, but the welded part may become a weak point due to metal fatigue. Therefore, reinforcement without welding is also being considered.

For example, a technique is known in which a reinforcing material is joined to both sides of a web with a bolt to reinforce (for example, see Patent Document 1).
Further, in order to reinforce the H-shaped steel web, a stiffener jack is known in which the dimension is adjusted between the flanges of the H-shaped steel, and the upper end and the lower end are abutted against and fixed to the upper flange and the lower flange, respectively ( For example, refer nonpatent literature 1.).

Japanese Patent No. 5116708

Hirose Giken Co., Ltd. website, [Search on March 6, 2015], Internet <URL: https://www.hirose-giken.co.jp/products/chuck_jack.html>

However, since the technique of the above-mentioned Patent Document 1 uses an infinite number of bolts to join the reinforcing material to the web, it may take time to install the reinforcing material. It may not be applicable to places where it is difficult to finish construction outside.
In addition, if the stiffener jack is fixed between the upper flange and the lower flange and then the distance between the upper flange and the lower flange may increase due to a load or vibration acting on the bridge girder, the stiffener jack may be detached.

  The objective of this invention is providing the steel girder reinforcement structure which can reinforce suitably the steel girder which has a substantially H-shaped cross section.

In order to achieve the above object, the present invention provides:
A steel girder reinforcement structure for reinforcing a steel girder having a substantially H-shaped cross section formed by connecting an upper flange and a lower flange with a web,
The steel girders are arranged in parallel with each other in pairs,
It is arranged through the lower surface side of the lower flange of each of the pair of steel girders so as to span the pair of steel girders, one end is connected to the upper flange of one steel girder and the other end is the other With a rope-shaped member connected to the upper flange of the steel girder,
The rope is provided with a tension in a direction in which both ends of the rope are drawn together.

The steel girder reinforcing structure having such a structure is arranged in contact with the lower surface of each lower flange so as to cross over a pair of steel girders, and one end is connected to the upper flange of one steel girder and the other end The steel member is provided with a rope-like member connected to the upper flange of the other steel girder, and the tension applied to the rope-like member acts in the direction of separating the upper flanges of the pair of steel girders from each other. Therefore, the steel girder can be reinforced so that the swing of the web of the pair of steel girders tilted toward the opposite steel girder is suppressed, and fatigue cracks are generated and progressed due to out-of-plane deformation of the web Can be suppressed.
For example, even when a load is applied such that the center side of the floor slab installed on the pair of steel girders is bent downward, and the load acts on the web of the pair of steel girders, Fatigue cracking caused by out-of-plane deformation of the web by suppressing the swinging of the web of the pair of steel girders that tilts toward the opposite steel girder as the tension applied to the rope-shaped member becomes a resistance force Occurrence and progression can be suppressed.
With such a steel girder reinforcement structure, a steel girder having a substantially H-shaped cross section can be suitably reinforced.

Also, preferably
The rope-like member is provided with tension adjusting means for adjusting the tension of the rope-like member.

If tension adjusting means capable of adjusting the tension of the rope-shaped member is provided, after the end of the rope-shaped member is connected to the upper flange of the steel beam, post-stress is applied to the rope-shaped member. The tension in the direction in which both ends are attracted to the rope-shaped member can be applied, and the strength of the tension can be adjusted.
If the steel girder reinforcement structure with tension adjusting means is used, the tension of the rope-like member is adjusted to an appropriate value, and the swinging of the pair of steel girder webs tilting toward the opposite steel girder is suppressed. Suitable reinforcement can be performed.

Also, preferably
The lower flange of one steel girder of the pair of steel girders is provided with a projecting member projecting in a direction away from the other steel girder,
The lower flange of the other steel girder is provided with a projecting member that projects in a direction away from the one steel girder,
The rope-shaped member is arranged through the lower surface side of the projecting member and the lower flange.

A projecting member that protrudes outward from the pair of steel girders is provided on the lower flange of the steel girder, and the tug-like member is hung on the projecting member, and both ends of the tug-like member are respectively attached to the upper flange. If connected, it will become easy to make the tension | tensile_strength provided to the rope-shaped member act in the direction which spaces apart the upper flange of the steel girder which makes a pair.
That is, if it is a steel girder reinforcement structure provided with an overhang member, reinforcement that suppresses swinging such that the web of the pair of steel girders tilts toward the opposite steel girder can be performed more suitably. Generation and progression of fatigue cracks due to out-of-plane deformation of the web can be suppressed.

Also, preferably
The upper flange of one steel girder of the pair of steel girders is provided with a projecting member projecting in a direction away from the other steel girder,
The upper flange of the other steel girder is provided with a projecting member that projects in a direction away from the one steel girder,
Each end of the rope-shaped member is fixed to the projecting member, and is connected to the upper flange via the projecting member.

If the steel girder's upper flange is provided with a projecting member that projects outward from the pair of steel girders, and both ends of the tug-shaped member are fixed to the projecting member, The applied tension can be easily applied in the direction in which the upper flanges of the pair of steel girders are separated from each other.
That is, if it is a steel girder reinforcement structure provided with an overhang member, reinforcement that suppresses swinging such that the web of the pair of steel girders tilts toward the opposite steel girder can be performed more suitably. Generation and progression of fatigue cracks due to out-of-plane deformation of the web can be suppressed.

Also, preferably
Biasing means comprising elastic members that can be expanded and contracted between the first member and the second member are respectively installed on opposite sides of the surfaces of the pair of steel girder webs facing each other, and the first member Is brought into contact with the upper flange, the second member is brought into contact with the lower flange, and an urging force in a direction to separate the upper flange and the lower flange is applied by an elastic restoring force of the elastic member. .

The biasing means respectively installed on the opposite side of the surface where the web of the pair of steel girders is facing biases the upper flange and the lower flange away from each other. The steel girder can be reinforced so as to suppress swinging in a direction away from the opposing steel girder, and the occurrence and progression of fatigue cracks due to out-of-plane deformation of the web can be suppressed.
In other words, with this steel girder reinforcement structure, the biasing means can suppress swinging such that the pair of steel girder webs are tilted away from the opposing steel girder, and by the rope-shaped member, Since the swinging of the web of the pair of steel girders that tilts toward the opposite steel girder can be suppressed, the out-of-plane deformation of the web is further suppressed, and the occurrence of fatigue cracks due to the out-of-plane deformation And progress can be suppressed.

  According to the present invention, a steel girder having a substantially H-shaped cross section can be suitably reinforced.

It is a front view which shows the steel girder reinforcement structure of this Embodiment 1. It is a perspective view which shows the principal part of the steel girder reinforcement structure of this Embodiment 1. It is a front view which shows other embodiment of the steel girder reinforcement structure. It is a front view which shows other embodiment of the steel girder reinforcement structure. It is a front view which shows the steel girder reinforcement structure of this Embodiment 2. It is a front view which shows the steel girder reinforcement structure of this Embodiment 3. It is a front view (a) and (b) which show the steel girder reinforcement structure of this Embodiment 4. It is explanatory drawing regarding the out-of-plane deformation | transformation of the web of H-section steel.

  Hereinafter, embodiments of a steel girder reinforcing structure according to the present invention will be described in detail with reference to the drawings. However, the embodiments described below are given various technically preferable limitations for carrying out the present invention, but the scope of the present invention is not limited to the following embodiments and illustrated examples.

(Embodiment 1)
FIG. 1 is a front view showing a steel girder reinforcement structure 100. FIG. 2 is a perspective view showing a main part of the steel girder reinforcement structure 100.
The steel girder reinforcing structure 100 is a structure for reinforcing a steel girder 1 having a substantially H-shaped cross section formed by connecting an upper flange 1a and a lower flange 1b with a web 1c.
The steel girder 1 is disposed on a support structure 2 such as a pier or an abutment via a gutter 4, and a floor slab 3 on which a track can be laid is laid on the steel girder 1.

The steel girder reinforcement structure 100 of this embodiment forms a pair in order to reinforce the steel girder 1 arranged in pairs in parallel directions as shown in FIGS. 1 and 2, for example. A rope-like member 10 is provided across the steel girder 1.
The rope-like member 10 is arranged through the lower surface side of each lower flange 1b of the pair of steel girders 1, the one end 10a is connected to the upper flange 1a of one steel girder 1, and the other end 10b is the other. Is connected to the upper flange 1a of the steel girder 1.
A tension (tension) in a direction in which both ends of the rope-shaped member 10 are attracted to each other is applied to the rope-shaped member 10.

Specifically, the rope-shaped member 10 is arranged in contact with the lower surface of the lower flange 1b of the steel girder 1, and the lower surface and the outer end surface of the lower flange 1b of the steel beam 1 which are paired at both ends of the rope-shaped member 10 are provided. It is bent so as to change its direction upward at the intersecting edge portion, and both ends (one end portion 10a and the other end portion 10b) of the rope-shaped member 10 are connected to the outer end surface of the upper flange 1a.
And the tension | tensile_strength of the rope-shaped member 10 acts in the direction which spaces apart the upper flange 1a of the steel girder 1 which makes a pair.

In this embodiment, the rope-shaped member 10 is disposed in the vicinity of the place where the rod 4 is installed. For example, as shown in FIG. 2, the two rope-shaped members 10 are attached in an arrangement sandwiching the rod 4. .
Note that the rope-like member 10 spanned between the pair of steel girders 1 extends in a direction perpendicular to the bridge axis and is arranged in a direction perpendicular to the steel girders 1.

The rope-like member 10 is, for example, a cable or a wire having a large tensile strength and flexibility, and specifically, a PC strand can be used.
Both end portions (one end portion 10a and the other end portion 10b) of the rope-shaped member 10 are fixed to the outer end surface of the upper flange 1a of the steel beam 1 by a fixing member 11 such as an anchor bolt.

  For example, the rope-shaped member 10 has a slightly shorter size than the path spanned by the pair of steel girders 1. When the end of the rope-shaped member 10 is fixed to the upper flange 1a of the steel girder 1, the rope-shaped member 10 is prestressed and extended by using predetermined equipment or the like. By removing the equipment after fixing the one end portion 10a and the other end portion 10b to the upper flange 1a, it is possible to apply tension in a direction in which both ends are attracted to the rope-shaped member 10.

  Moreover, it is preferable to perform well-known surface treatments, such as a fluorine coating, in order to reduce the frictional resistance of the lower surface of the lower flange 1b of the steel girder 1 which the rope-shaped member 10 contacts. In particular, it is preferable to perform a polishing process such as chamfering so that an edge portion where the lower surface 1b of the lower flange 1b of the steel girder 1 and the outer end surface contact with the rope-shaped member 10 forms a curved surface.

As described above, the steel girder reinforcing structure 100 of the present embodiment is arranged in a state where it is in contact with the lower surface of the lower flange 1b of the steel girder 1 forming a pair, and the one end 10a and the other end 10b form a pair. 1 is provided with a rope-like member 10 fixed to the outer end face of each upper flange 1a, and the tension applied to the rope-like member 10 separates the upper flanges 1a of the pair of steel girders 1 from each other. Therefore, the steel girder 1 can be reinforced so as to suppress the swinging of the web 1c of the steel girder 1 forming a pair toward the opposite steel girder 1. The occurrence and progression of fatigue cracks due to out-of-plane deformation can be suppressed.
For example, even when a load is applied such that the center side of the floor slab 3 installed on the pair of steel girders 1 is bent downward, and the load acts on the web 1c of the pair of steel girders 1, this steel The tension applied to the rope-like member 10 of the girder reinforcing structure 100 becomes a resistance force, and the swinging of the web 1c of the steel girder 1 forming a pair toward the opposing steel girder 1 is suppressed. Generation and progression of fatigue cracks due to the out-of-plane deformation of 1c can be suppressed.
With such a steel girder reinforcing structure 100, the steel girder 1 having a substantially H-shaped cross section can be suitably reinforced.

In particular, this steel girder reinforcing structure 100 fixes both ends (one end 10 a and the other end 10 b) of the rope-shaped member 10 to the outer end face of the upper flange 1 a of the steel girder 1 using the fixing member 11. Therefore, there is no place to be welded, and the steel girder 1 can be reinforced in a short time.
Moreover, since the rope-shaped member 10 is not welded to the steel girder 1, the work of replacing the broken rope-shaped member 10 or replacing the rope-shaped member 10 having a different tension can be easily performed. .
Further, even if the distance between the upper flange 1a and the lower flange 1b varies due to a load or vibration acting on the steel girder 1, the rope-like member 10 does not come off unlike the conventional stiffener jack.

The present invention is not limited to the above embodiment.
For example, as shown in FIG. 3, the rope-shaped member 10 may be provided with tension adjusting means 12 that adjusts the tension of the rope-shaped member 10.
The tension adjusting means 12 is, for example, a turnbuckle, and the tension applied to the rope-shaped member 10 can be switched by adjusting tightening of bolts on both sides of the turnbuckle.
In the case of the rope-like member 10 provided with the tension adjusting means 12, after fixing the end of the rope-like member 10 to the upper flange 1a of the steel girder 1, the bolt of the turnbuckle is tightened, for example. By applying post-stress to 10, tension in a direction in which both ends are attracted to the rope-shaped member 10 can be applied.
If it is the steel girder reinforcement structure 100 which has such a tension adjustment means 12, the tension | tensile_strength member 10's tension | tensile_strength is adjusted to an appropriate value, and the web 1c of the steel girder 1 which makes a pair is toward the steel girder 1 which opposes. A suitable reinforcement that suppresses tilting swinging can be performed.

Moreover, the tension adjusting means 12 provided in the rope-shaped member 10 is not limited to a turnbuckle, and may be a hydraulic jack as shown in FIG.
The hydraulic jack as the tension adjusting means 12 includes a rod 12b that moves up and down from a cylinder 12a installed in the support structure 2, and supports the rope-like member 10 at the tip of the rod 12b. By raising the rod 12b of the hydraulic jack and applying post stress to the rope-like member 10, tension in a direction in which both ends are attracted to the rope-like member 10 can be applied.
If it is the steel girder reinforcement structure 100 which has such a tension adjustment means 12, the tension | tensile_strength member 10's tension | tensile_strength is adjusted to an appropriate value, and the web 1c of the steel girder 1 which makes a pair is toward the steel girder 1 which opposes. A suitable reinforcement that suppresses tilting swinging can be performed.

(Embodiment 2)
Next, Embodiment 2 of the steel girder reinforcement structure according to the present invention will be described. In addition, the same code | symbol is attached | subjected to the same part as Embodiment 1, and only a different part is demonstrated.

As shown in FIG. 5, the steel girder reinforcing structure 100 of the second embodiment has a structure in which a protruding member 20 is provided on each of the lower flanges 1 b of the steel girder 1 forming a pair.
The overhang member 20 is a steel plate-like member, for example, and is fixed to the outer end surface of the lower flange 1b with a bolt or the like.

Specifically, the lower flange 1b of one steel girder 1 is provided with a projecting member 20 that projects in a direction away from the other steel girder 1, and the lower flange 1b of the other steel girder 1 has An overhang member 20 is provided that projects in a direction away from one steel girder 1.
And the rope-shaped member 10 is distribute | arranged through the lower surface side of the overhang | projection member 20 and the lower flange 1b, and both ends (one end part 10a, the other end part 10b) of the rope-shaped member 10 are fixed by the fixing member 11. The steel girder 1 is fixed to the outer end face of the upper flange 1a.

In this way, if the projecting member 20 that projects outward from the pair of steel girders 1 is provided and the tug member 10 is hung on the projecting member 20, the tension applied to the tug member 10 Are easily acted in the direction in which the upper flanges 1a of the pair of steel beams 1 are separated from each other.
In other words, if the steel girder reinforcement structure 100 provided with the projecting member 20 is used, the reinforcement that suppresses the swinging of the web 1c of the steel girder 1 that forms a pair toward the steel girder 1 that faces is more preferable. It is possible to suppress the occurrence and progression of fatigue cracks due to out-of-plane deformation of the web 1c.
Therefore, the steel girder reinforcing structure 100 can suitably reinforce the steel girder 1 having a substantially H-shaped cross section.

(Embodiment 3)
Next, Embodiment 3 of the steel girder reinforcement structure according to the present invention will be described. In addition, the same code | symbol is attached | subjected to the same part as Embodiment 1, and only a different part is demonstrated.

As shown in FIG. 6, the steel girder reinforcing structure 100 of the third embodiment has a structure in which an overhang member 30 is provided on each of the upper flanges 1 a of the steel girder 1 forming a pair.
The overhang member 30 is a steel plate-like member, for example, and is fixed to the outer end surface of the upper flange 1a with bolts or the like.

Specifically, the upper flange 1a of one steel girder 1 is provided with a projecting member 30 that projects in a direction away from the other steel girder 1, and the upper flange 1a of the other steel girder 1 has An overhang member 30 is provided to project in a direction away from one steel girder 1.
And each end part (one end part 10a, the other end part 10b) of the rope-shaped member 10 is being fixed to the end surface of the overhanging member 20 by the fixing member 11, and the rope-like member 10 is interposed via the overhanging member 30. And is connected to the upper flange 1a.

In this way, if the projecting member 30 projecting outward from the pair of steel girders 1 is provided and the tug member 10 is fixed to the projecting member 30, the tension applied to the tug member 10 Are easily acted in the direction in which the upper flanges 1a of the pair of steel beams 1 are separated from each other.
That is, if the steel girder reinforcement structure 100 provided with the projecting member 30 is used, the reinforcement that suppresses the swinging of the web 1c of the steel girder 1 that forms a pair toward the opposing steel girder 1 is more preferable. It is possible to suppress the occurrence and progression of fatigue cracks due to out-of-plane deformation of the web 1c.
Therefore, the steel girder reinforcing structure 100 can suitably reinforce the steel girder 1 having a substantially H-shaped cross section.

(Embodiment 4)
Next, Embodiment 4 of the steel girder reinforcement structure according to the present invention will be described. In addition, the same code | symbol is attached | subjected to the same part as Embodiment 1, and only a different part is demonstrated.

For example, as shown in FIGS. 7 (a) and 7 (b), the steel girder reinforcing structure 100 of the fourth embodiment is provided with urging means 50 on the opposite side of the surface where the web 1c of the steel girder 1 forming a pair faces. It has a structure where is installed.
In addition, the steel girder reinforcement structure 100 shown to Fig.7 (a) adds the biasing means 50 to the steel girder reinforcement structure 100 of Embodiment 2. FIG.
Moreover, the steel girder reinforcement structure 100 shown in FIG.7 (b) adds the urging means 50 to the steel girder reinforcement structure 100 of Embodiment 3. FIG.

The biasing means 50 is arranged between the cylinder 51 that is the first member, the shaft 52 that is the second member attached to the cylinder 51 so as to be able to appear and retract, and the cylinder 51 and the shaft 52. And an elastic member 53 that can be expanded and contracted.
The cylindrical body 51 has a cylindrical shape whose upper end is closed by the top surface portion, and a shaft body 52 is inserted into the cylindrical body 51 from the opening on the lower end side.
The shaft body 52 is disposed in the cylinder body 51 so as to be able to advance and retract in the axial direction.
The elastic member 53 is a spring member (here, a coil spring), for example, and has one end abutted against the cylindrical body 51 and the other end abutted against the shaft body 52. The elastic member 53 biases the cylindrical body 51 and the shaft body 52 in a direction in which they are separated from each other.

The urging means 50 presses the upper surface (top surface portion) of the cylindrical body 51 against the upper flange 1a by a repulsive force (elastic restoring force) that the elastic member 53 inserted in the cylindrical body 51 expands, and thereby the shaft body. The lower surface of 52 is pressed against the lower flange 1b, the cylinder body 51 is pressed toward the upper flange 1a, and the shaft body 52 is pressed toward the lower flange 1b.
That is, the urging means 50 applies the urging force in the direction in which the upper flange 1a and the lower flange 1b are separated from each other by bringing the cylindrical body 51 into contact with the upper flange 1a and the shaft body 52 in contact with the lower flange 1b. Yes.

Thus, the urging means 50 installed on the opposite side of the surface where the web 1c of the pair of steel girders 1 is opposed is urged in the direction of separating the upper flange 1a and the lower flange 1b. Therefore, the steel girder 1 can be reinforced so that the web 1c of the pair of steel girders 1 is tilted in a direction away from the opposing steel girder 1 and is caused by out-of-plane deformation of the web 1c. Generation and progression of fatigue cracks can be suppressed.
In particular, the urging means 50 can be installed between the upper flange 1a and the lower flange 1b using the force (repulsive force) that the elastic member 53 expands. The steel girder 1 can be reinforced in a short time without welding.

That is, in this steel girder reinforcement structure 100, the urging means 50 can suppress swinging such that the web 1c of the steel girder 1 forming a pair is inclined away from the opposing steel girder 1; Since the swaying of the web 1c of the pair of steel girders 1 tilting toward the opposing steel girder 1 can be suppressed by the member 10, the out-of-plane deformation of the web 1c is further suppressed, Generation and progression of fatigue cracks due to external deformation can be suppressed.
Therefore, according to this steel girder reinforcing structure 100, the steel girder 1 having a substantially H-shaped cross section can be reinforced more suitably.

The urging means 50 installed between the upper flange 1a and the lower flange 1b presses the cylindrical body 51 toward the upper flange 1a by the repulsive force of the elastic member 53, and the shaft body 52 is pressed against the lower flange 1b. Since the distance between the upper flange 1a and the lower flange 1b may slightly increase due to the load or vibration acting on the steel girder 1, the cylinder 51 is pressed against the upper flange 1a. Since the shaft body 52 can be press-contacted to the lower flange 1b, it does not come off like the conventional stiffener jack.
Further, since the urging means 50 is not welded to the steel beam 1, it is possible to easily perform the work of exchanging the urging means 50 in which a problem has occurred or exchanging the urging means 50 with a different spring force. it can.

  In the above embodiment, the floor slab 3 is installed on the two steel girders 1, and the rope-like member 10 is bridged between the steel girders 1 forming a pair. It is not limited. For example, when the floor slab 3 is erected on three steel girders 1, the steel girder 1 on both sides forms a pair, that is, the outermost two steel girders 1 have ropes. The structure spanning 10 is also a steel girder reinforcement structure of the present invention.

Further, in the above embodiment, the protruding members 20 are provided on the lower flanges 1b of the pair of steel girders 1, but the present invention is not limited to this, and the pair of steel girders is provided. 1, the overhang member 20 may be provided on at least one of the lower flanges 1b. Even in the steel girder reinforcement structure 100 including the projecting member 20 on one lower flange 1b, the steel girder 1 having a substantially H-shaped cross section can be suitably reinforced by the tension applied to the rope-shaped member 10. it can.
Moreover, in the above embodiment, although the overhanging member 30 was each provided in the upper flange 1a of the steel girder 1 which makes a pair, this invention is not limited to this, The steel girder which makes a pair 1, the overhang member 30 may be provided on at least one of the upper flanges 1a. Even in the steel girder reinforcement structure 100 having the overhanging member 30 on one upper flange 1a, the steel girder 1 having a substantially H-shaped cross section can be suitably reinforced by the tension applied to the rope-shaped member 10. it can.

  In addition, it is needless to say that other specific detailed structures can be appropriately changed.

DESCRIPTION OF SYMBOLS 1 Steel girder 1a Upper flange 1b Lower flange 1c Web 2 Support structure 3 Floor slab 4 Tensile member 10a One end part 10b Other end part 11 Fixing member 12 Tension adjusting means 20 Overhang member 30 Overhang member 50 Energizing means 51 cylinder (first member)
52 Shaft body (second member)
53 Elastic member 100 Steel girder reinforcement structure

Claims (5)

A steel girder reinforcement structure for reinforcing a steel girder having a substantially H-shaped cross-section formed by connecting an upper flange and a lower flange with a web and arranged in parallel with each other,
It is arranged through the lower surface side of the lower flange of each of the pair of steel girders so as to span the pair of steel girders, one end is connected to the upper flange of one steel girder and the other end is the other With a rope-shaped member connected to the upper flange of the steel girder,
A steel girder reinforcing structure characterized in that a tension in a direction in which both ends of the rope-shaped member are attracted is applied to the rope-shaped member.   The steel girder reinforcement structure according to claim 1, wherein the rope-shaped member is provided with tension adjusting means for adjusting the tension of the rope-shaped member. The lower flange of one steel girder of the pair of steel girders is provided with a projecting member projecting in a direction away from the other steel girder,
The lower flange of the other steel girder is provided with a projecting member that projects in a direction away from the one steel girder,
3. The steel girder reinforcing structure according to claim 1, wherein the rope-shaped member is disposed through a lower surface side of the projecting member and the lower flange. The upper flange of one steel girder of the pair of steel girders is provided with a projecting member projecting in a direction away from the other steel girder,
The upper flange of the other steel girder is provided with a projecting member that projects in a direction away from the one steel girder,
3. The steel girder reinforcement according to claim 1, wherein each end of the rope-shaped member is fixed to the projecting member and connected to the upper flange via the projecting member. Construction.   Biasing means comprising elastic members that can be expanded and contracted between the first member and the second member are respectively installed on opposite sides of the surfaces of the pair of steel girder webs facing each other, and the first member Is in contact with the upper flange, the second member is in contact with the lower flange, and an urging force in a direction to separate the upper flange and the lower flange is applied by an elastic restoring force of the elastic member. The steel girder reinforcement structure according to any one of claims 1 to 4.

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