JP2828622B2 - Steel building material for seismic reinforcement of existing RC structures and method of seismic reinforcement of existing RC structures - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a building material made of steel for seismic reinforcement and reinforcement of existing reinforced concrete structures (hereinafter referred to as existing RC structures) such as road bridges and railway bridges to improve seismic resistance. The present invention relates to a method of reinforcing an existing RC structure using building materials.

[0002]

2. Description of the Related Art As a method of reinforcing an existing RC structure (generally, a pier) such as a road bridge or a railway bridge, a bending strength control type steel sheet winding method has been proposed. As shown in FIG. 7, this construction method has a thickness of 6 to 1 on the outer peripheral surface of the existing RC structure K.
A plurality of steel plates (SS400) 21 of about 2 mm are fixed with a large number of anchor bolts 22 and the steel plates 21 are connected in a ring shape to surround the existing RC structure K.
A gap g formed between the C structure K and the steel plate 21 is filled with a curable material 23 such as non-shrink mortar or epoxy resin in a fluidized state and hardened.
Is integrated with the curable material 23 to improve the toughness and proof stress of the structure. The base of the steel plate 21 is fixed to the footing Ka with an anchor bar 25 via a shaped steel 24 welded to the base, and the portion is covered with concrete 26.

[0003]

The joining of a plurality of steel plates 21 wound around the existing RC structure K is performed by welding, but has the following problems. .

(1) Since welding is performed on site, quality problems are likely to occur, and it is difficult to obtain a certain bonding strength. (2) Since almost all of the reinforcement work must be performed on site, the construction period is long. (3) On-site work is limited in time within a day (sometimes 3 to 4 hours), and the work site is often narrow, so large machines such as automatic welding machines are used. In this case, since it takes a long time to carry in and carry out, the reinforcement work cannot be performed efficiently in this regard.

[0005]

According to a first aspect of the present invention, there is provided a steel building material for seismic retrofitting of an existing RC structure, wherein the side edges of the steel material are connected to each other, and the existing RC structure is provided. A steel building material for seismic reinforcement of an existing RC structure wound around the periphery of an existing RC structure so as to form a gap between the steel member and the existing RC structure, wherein a connecting protrusion and a fitting recess are provided side by side. The members are arranged on the outer sides of the fitting recesses with the fitting projections fixed to the both side edges of the steel plate, respectively , and the surface of the steel plate has countless irregularities.
Was formed .

[0006] The seismic reinforcement of the existing RC structure according to claim 2
Steel building materials are intended to join the side edges of each other
A gap is formed between the existing RC structure and the existing RC structure.
Steel for seismic reinforcement of existing RC structures wound around the perimeter of structures
A building material, in which a fitting convex portion and a fitting concave portion are juxtaposed.
The member is arranged on the outside of the fitting concave portion with the fitting convex portion,
A number of through holes are fixed to each side edge, and
And a configuration in which the screw hole is penetrated on the front and back and formed at a predetermined interval
did. The steel building materials for seismic reinforcement of the existing RC structures
And the inclination angle of the locking surface inside the fitting convex portion of the coupling member is
An angle smaller than 90 degrees, preferably 85 degrees
No. Also, the outer surface of the fitting projection of the coupling member is tapered with a taper.
Preferably, the slope is used.

According to a fifth aspect of the present invention, there is provided a method for seismic retrofitting of an existing RC structure, comprising the steps of: connecting a plurality of steel building materials for seismic retrofitting according to any one of the first to fourth aspects to each other with connecting members adjacent to each other. The fitting protrusion and the fitting recess are fitted to each other, and a gap is formed between the fitting RC and the existing RC structure.
Wrapped around the C structure, and the steel building material for seismic reinforcement is
The gap is fixed to the existing RC structure integrally with a curable material that is filled in a fluid state and hardened.

[0008] A seismic reinforcing steel building material is inserted into a through hole of a steel plate and a tip is screwed to an anchor nut provided on an existing RC structure, and another anchor provided on the existing RC structure. It is preferable that one end is screwed to the nut, and the other end whose screw direction is reversed is fixed in a predetermined state by a reverse screw bolt screwed into a screw hole of the steel plate.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described based on embodiments with reference to the drawings. In FIG. 1, an existing RC structure K such as a road bridge or a railway bridge has a rectangular cross section. The symbol Kb is a reinforcing bar, and Kc is a band bar.

The steel building material 1 for seismic reinforcement of the existing RC structure according to the present invention is wound around the outer periphery of the existing RC structure K. As shown in FIG. The coupling member 2 having the fitting recesses 2b arranged side by side and the coupling member 3 having the fitting projections 3a and the fitting recesses 3b arranged side by side are connected to the fitting projections 2a, 3a. 3b, placed outside the steel plate 4
Are individually welded to both side edges of the. Reference numeral 5 denotes the welding portion, which is a groove welding.

The connecting members 2 and 3 have the same cross-sectional shape as each other, and one connecting member 2 has the fitting convex portion 2a and the fitting concave portion 2b directed to the inner peripheral side, that is, the existing RC structure K side. At the same time, the contact surface 2c opposite to the fitting convex portion 2a and the fitting concave portion 2b is brought into contact with the inner surface of the steel plate 4 and welded to the steel plate 4, and the other connecting member 3 is connected to the fitting convex portion and the fitting concave portion. 3b
To the outer peripheral side, and the contact surface 3 d on the side of the fitting convex portion 3 a and the fitting concave portion 3 b is brought into contact with the inner surface of the steel plate 4.
Welded to.

Also, the fitting projections 2a, 3 of the coupling members 2, 3
a, that is, the surfaces on the side of the fitting recesses 2b, 3b
e, 3e, and the outer surface is a tapered inclined surface 2f, 3e.
3f. Angle of inclination θ of locking surfaces 2e and 3e in the figure
Is 85 degrees, but may be other than 85 degrees if the angle is 90 degrees or smaller. The smaller the angle θ is, the harder it is to come off.

As shown in FIGS. 1 and 2, the connecting members 2 and 3 can be connected by fitting the fitting projections 2a and 3a and the fitting recesses 3b and 2b. ing.
The inclined surfaces 2f and 3f move the coupling members 2 and 3 relatively in the direction in which the fitting projections 2a and 3a and the fitting recesses 2b and 3b are arranged (left and right directions in FIG. 2). Are connected to each other to guide the fitting protrusions 2a, 3a to the mating recesses 3b, 2b on the other side, whereby the connection of the connecting members 2, 3 becomes smooth. For the coupling members 2 and 3, hot-pressed steel, deformed steel, or the like is used.

The steel plate 4 is formed by bevel welding a flat plate 4b to both side edges of an angle member 4a, and a large number of through holes 4c and screw holes 4d are formed at predetermined intervals through the front and back. . In the drawing, only one through hole 4c and one screw hole 4d are shown. Reference numeral 6 denotes a weld between the angle member 4a and the flat plate 4b.

As shown in FIG. 1, when the steel plate 4 and the connecting members 2 and 3 of the steel building material 1 for seismic reinforcement are wound around the existing RC structure K, as shown in FIG. The size and shape are such that the gap g is formed. The shape of the steel building material 1 for seismic reinforcement is not limited to a square shape but may be an arc shape as shown in FIG. The arc-shaped steel building material 1 is usually used for reinforcing an existing RC structure K having a circular cross-sectional shape. In the case of the arc-shaped building material 1, the shapes of the coupling members 2 and 3 are not the same.

As the steel plate 4, a deck plate having a myriad of irregularities formed on its surface can be used. As shown in FIGS. 5 and 6, the steel plate 4 and the joining members 2 and 3 may be welded with their end faces abutting each other, and the joining members 2 and 3 may be attached to the outer surface of the steel plate 4 as shown in FIG. The welding may be performed so that the side is the structure K side.

A large number of anchor nuts 7 and 8 are buried at predetermined intervals on the surface of the generator of the existing RC structure K. Anchor nuts 7 and 8, through hole 4 c and screw hole 4 of steel plate 4
d is correctly opposed to the end of the fixing bolt 9 inserted into the through hole 4c of the steel plate 4 and the screw hole 4d of the steel plate 4.
The ends of the reverse threaded bolts 10 screwed into the anchor nuts 7 and 8 are individually screwed into the anchor nuts 7 and 8, respectively, so that the outer surface of the steel building material 1 for seismic reinforcement can be regulated to a predetermined state. .

As shown in FIG. 4, the reverse threaded bolt 10 is
The screw direction of one end 10a and the other end 10b is reversed, and a square hole 10c for turning the reverse screw bolt 10 is formed at one end. Anchor nuts 7, 8
Can have the same structure or different structures.

The steel building material 1 for seismic reinforcement is usually made of a steel plate 4
The main processing such as welding of the connecting members 2 and 3 or all the processing is performed at a factory to manufacture. The necessary number (four in the case of FIG. 1) of the steel building materials 1 are arranged around the existing RC structure K at the site, and the connecting members 2 and 3 are connected to each other and wound around the existing RC structure K. And fixing bolt 9
And the reverse screw 10 are screwed to the anchor nuts 7 and 8 and fixed to the existing RC structure K. A gap g is formed between the existing RC structure K and the building material 1 by winding the steel building material 1.

When the fixing bolt 9 is screwed deeply into the anchor nut 7, the gap g is narrowed, and the reverse screw 10 is
Since the size of the gap g can be freely changed depending on the rotation operation direction, the steel building material 1 can be operated by operating both bolts 9 and 10.
The outer surface of the can be flattened, for example flat. In addition, the reverse screw bolt 10 has one end previously screwed slightly into the screw hole 4d or into the anchor nut 8, and the reverse screw bolt 1 is inserted in a direction in which the gap g is narrowed.
0 is rotated to screw the other end into the anchor nut 8 or the screw hole 4d.

An ordinary bolt may be screwed into the screw hole 4d and its tip may be abutted against the surface of the existing RC structure K to cooperate with the fixing bolt 9 to bring the steel building material 1 into a predetermined state.

As described above, the connecting members 2 and 3 are connected by moving the steel building material 1 in the direction in which the fitting projections 2a and 3a and the fitting recesses 2b and 3b are arranged (lateral direction) by a machine or the like. Do
In some cases, the connecting members 2 and 3 may be connected by moving the steel building material 1 vertically.

When the existing RC structure K is high, the steel building material 1 is divided into two or more upper and lower stages and wound around the existing RC structure K,
They are welded horizontally and integrated.
In this case, the positions of the connecting members 2 and 3 of the steel building materials 1 and 1 connected vertically can be vertically aligned at the same position, or they can be staggered.

After winding and fixing the steel building material 1 around the existing RC structure K, the gap g is filled with a curable material 23 such as non-shrink mortar, epoxy resin or concrete in a fluid state and cured. The steel building material 1 is integrally fixed to the existing RC structure K by hardening of the hardenable material 23, and enhances the toughness and the proof stress of the existing RC structure K to reinforce the existing RC structure K. When the steel plate 4 is used as a deck plate, the contact area with the curable material 23 is increased by the countless irregularities formed on the surface thereof, and the plate is more firmly fixed.

The end face of the steel building material 1 for seismic reinforcement is
Since it is generally matched to the outer shape of the C structure K, it is not limited to those shown in FIGS. Also,
Since the number of windings of the steel building material 1 around the existing RC structure K is two or more, the shape changes depending on the number.
Although the steel building material 1 is fixed to the footing Ka as shown in FIG. 7, another structure may be adopted.

[0026]

As described above, the steel building material for seismic reinforcement of the existing RC structure according to claim 1 connects the side edges of each other to each other and forms a gap between the existing RC structure and the existing RC structure. Existing R formed and wound around the outer circumference of the existing RC structure
A steel building material for earthquake-resistant reinforcement of a C-structure, wherein a connecting member having a fitting projection and a fitting recess arranged side by side disposes the fitting projection outside the fitting recess, and forms both side edges of the steel plate. each is fixed to, or
3. A steel for seismic reinforcement of an existing RC structure according to claim 2, wherein the steel plate has a structure in which countless irregularities are formed on a surface thereof.
The building material is a connecting member in which a fitting convex portion and a fitting concave portion are juxtaposed.
However, the fitting projection is arranged outside the fitting recess so that both sides of the steel plate
Each of the steel plates is fixed to the edge, and the steel plate has many through holes.
And screw holes penetrated on the front and back and formed at predetermined intervals
Since all of them can be manufactured in a factory using an automatic welding machine or the like, it is possible to efficiently and cost-effectively produce a high quality steel building material 1 for seismic reinforcement. Further, at the work site, it is only necessary to mainly perform operations such as winding a steel building material produced at the factory and injecting a curable material into the gap, so that the construction period can be significantly reduced.

In addition, the seismic retrofit of the existing RC structure according to claim 1 is provided.
As described above, the heavy steel building material uses a steel plate having a myriad of irregularities formed on its surface as described above, so that the steel plate is firmly fixed by the irregularities. An existing RC structure according to claim 2
As mentioned above, steel building materials for seismic retrofitting use steel plates formed at predetermined intervals through a large number of through holes and screw holes as described above .
As a result, the steel building material can be correctly fixed in a predetermined state using a fixing bolt or a reverse screw bolt.

According to a fifth aspect of the present invention, there is provided a method for seismic retrofitting of an existing RC structure, comprising the steps of: connecting a plurality of steel building materials for seismic retrofitting according to any one of the first to fourth aspects to each other by connecting connecting members adjacent to each other. The fitting protrusion and the fitting recess are fitted to each other, and a gap is formed between the fitting RC and the existing RC structure.
Wrapped around the C structure, and the steel building material for seismic reinforcement is
It is configured to be integrally fixed to the existing RC structure by a curable material filled and hardened in the gap in a fluid state,
Since the toughness and proof stress are greatly improved by the steel building material for seismic reinforcement, the strength of the existing RC structure is sufficiently enhanced. Also, the workability is improved.

[0029] A seismic strengthening steel building material is inserted into a through hole of a steel plate and a tip is screwed to an anchor nut provided on the existing RC structure, and another anchor provided on the existing RC structure. When one end is screwed to the nut and the other end whose screw direction is reversed is fixed in a predetermined state by a reverse screw bolt screwed into the screw hole of the steel plate, a steel building material is used. Since the winding state can be easily adjusted to a predetermined state, the existing RC structure can be reinforced as designed.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing an example of an existing RC structure reinforced with a steel building material for earthquake-resistant reinforcement according to the present invention.

FIG. 2 is a diagram illustrating a coupling state of a coupling member.

FIG. 3 is a diagram showing a coupling state of another coupling member.

FIG. 4 is a view showing an example of a reverse threaded bolt with a part broken.

5 is a view showing a welding example different from FIG. 2 of the steel plate and the coupling member.

FIG. 6 is a view showing a welding example different from FIG. 3 of the steel sheet and the coupling member.

FIG. 7 is a longitudinal sectional view for explaining a bending strength control type steel sheet winding method.

[Explanation of symbols]

 K Existing RC structure Ka Footing Kb Reinforcing bar Kc Stirrup g Gap 1 Steel building material for seismic reinforcement 2, 3 Connecting member 2a, 3a Fitting convex portion 2b, 3b Fitting concave portion 2c, 3d Contact surface 2e, 3e Locking surface 2f, 3f Inclined surface 4 Steel plate 4a Angle material 4b Flat plate 4c Through hole 4d Screw hole 5,6 Welded part 7,8 Anchor nut 9 Fixing bolt 10 Reverse screw bolt 10a One end 10b Other end 10c Square hole

──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Akio Miki 1-51-7-106, Minami, Suginami-ku, Tokyo (72) Inventor Ikiyuki Kanzawa 2-20-13, Hiramachi, Meguro-ku, Tokyo (72) Invention Hiroshi Nakayama 1-16-14 Shibuya, Shibuya-ku, Tokyo Tokyu Construction Co., Ltd. (72) Inventor Kunito Sakai 1-16-114 Shibuya, Shibuya-ku, Tokyo Tokyu Construction Co., Ltd. (72) Inventor Seiichi Naito 1-4-12 Kozono, Ayase City, Kanagawa Prefecture (72) Inventor Noriyuki Kawabata 2-3-6 Otemachi, Chiyoda-ku, Tokyo Inside Nippon Steel Corporation (56) References JP-A-9-41565 (JP, A) (58) Field surveyed (Int. Cl. ⁶ , DB name) E01D 22/00 E01D 19/02 E04G 23/02

Claims (6)

(57) [Claims] 1. A steel for seismic reinforcement of an existing RC structure wound around an outer periphery of an existing RC structure by connecting side edges of each other to each other and forming a gap between the existing RC structure. A building material, wherein a coupling member having a fitting convex portion and a fitting concave portion arranged side by side is arranged on the outer side of the fitting concave portion , and is fixed to both side edges of the steel plate. A steel building material for seismic reinforcement of existing RC structures, characterized by having a myriad of irregularities formed on the surface . 2. A steel for seismic reinforcement of an existing RC structure wound around an outer periphery of an existing RC structure by connecting side edges of each other to each other and forming a gap between the existing RC structure. A building material, wherein a coupling member having a fitting convex portion and a fitting concave portion arranged side by side is arranged on the outer side of the fitting concave portion , and is fixed to both side edges of the steel plate , and is fixed to the steel plate. Has many through holes and screw holes
Seismic reinforcement steel building materials already set RC structures you characterized in that it is formed at a predetermined interval Te. 3. The inclination of the locking surface inside the fitting projection of the coupling member.
The angle of inclination is less than 90 degrees, preferably 85 degrees
The steel building material for seismic reinforcement of an existing RC structure according to claim 1 or 2, wherein the building material is made of steel. 4. The outer surface of the fitting projection of the connecting member is tapered.
4. An inclined surface as defined in claim 1, 2 or 3.
A steel building material for seismic reinforcement of the existing RC structure described in the above. 5. A plurality of seismic retrofitting steel building materials according to any one of claims 1 to 4 , wherein a fitting convex portion and a fitting concave portion of adjacent coupling members are fitted to each other. Together with the existing RC structure to form a gap
Wrapped around the C structure, and the steel building material for seismic reinforcement is
A seismic retrofitting method for an existing RC structure, wherein the space is integrally fixed to the existing RC structure with a curable material that is filled in a flow state and hardened. 6. A fixing bolt having a seismic strengthening steel building material inserted into a through hole of a steel plate and having a tip screwed to an anchor nut provided on an existing RC structure, and a fixing bolt provided on the existing RC structure. 6. An anchor nut according to claim 5 , wherein one end is screwed to said anchor nut and said other end is fixed in a predetermined state by a reverse screw bolt screwed into a screw hole of a steel plate. The seismic retrofitting method of the existing RC structure described in the above.