JP2013249726A - Seismic strengthening structure for existing steel-frame building - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a seismic strengthening structure for an existing building, which can relatively easily increase earthquake resistance without sacrificing an existing appearance.SOLUTION: In a seismic strengthening method for an existing steel-frame building 1, a reinforcing body 10 is fixedly attached to upper and lower beams 4 of an existing steel-frame building 1. The reinforcing body 10, which comprises a pair of reinforcing members 11 and 12 connected together in series by a connection body 23, is fixed to the beam 4 via a plate 40. Additionally, flange surfaces of H-shaped steel forming the beam 4 are connected together by a reinforcing plate 45.

Description

  The present application relates to a seismic reinforcing structure in an existing steel building.

  Various seismic reinforcement structures that improve the seismic resistance of existing steel buildings by reinforcing the frame have been considered.

  As one type of such a seismic reinforcement structure, there is known a structure in which steel braces and reinforced concrete walls are added in a column beam structure in a building to improve both rigidity and strength.

  The expansion of walls requires the filling of existing windows and the need to sacrifice ventilation, lighting and design.

  In addition, the installation of the brace may cause the necessity of sacrificing the entrance / exit, and the installation on the window may obstruct the field of view, and further, the appearance may be very poor.

  Therefore, in order to eliminate an example of such a problem, the present application provides a seismic reinforcement structure or the like in an existing steel building that can improve seismic resistance relatively easily without sacrificing the existing appearance. For the purpose.

  In order to solve the above-described problem, the seismic reinforcing structure in the existing steel building according to claim 1 of the present application is configured by fixing the reinforcing body (10) to the upper and lower beams (4) of the existing steel building (1). A seismic reinforcement structure for an existing steel structure to be attached, the reinforcement being arranged in parallel with a vertically extending column (2) constituting the existing steel structure and attached to the beam ( 11 and 12) and a connecting body (26) for connecting the reinforcing members in series, and an elastic body (21) is interposed between the connecting body and one reinforcing member side. It is characterized by.

  Moreover, the existing steel building of Claim 2 is an earthquake-proof reinforcement structure in the existing steel building of Claim 1, Said pair of reinforcement member has a clearance gap (t), and is connected by the coupling body. And a guide means (27) for moving the other reinforcing member in the vertical direction with respect to the one reinforcing member.

  Further, the seismic reinforcement method for an existing steel building according to claim 3 is a seismic reinforcement method for an existing steel building in which a reinforcing body is fixedly attached to the upper and lower beams of the existing steel building and is connected in series with the connecting body. The reinforcing body composed of a pair of reinforcing members connected together is fixed to the beam via a plate, and the flange surfaces of the H-shaped steel forming the beam are connected by a reinforcing plate. And

  Moreover, the reinforcement body of Claim 4 is a reinforcement body used for the seismic reinforcement structure in the existing steel building which fixes and attaches a reinforcement body to the upper and lower beams of an existing steel structure building, The said reinforcement body is A pair of reinforcing members which are arranged in parallel with the vertically extending columns constituting the existing steel building and are attached to the beam, and a connecting body which connects the reinforcing members in series. On the member side, an elastic body is interposed between the connecting body and the member.

FIG. 1A is a front view, FIG. 1B is a plan view, and FIG. 1C is a side view of the second floor portion. It is a figure which shows the attachment state of a reinforcement body. It is a figure which shows the lower pillar part of the AA cross section of FIG. It is a front view of a 1st connection part. It is BB sectional drawing of FIG. FIG. 3 is an enlarged view of part B of FIG. 2.

  Hereinafter, an embodiment of the present application will be described with reference to the accompanying drawings. The multi-layer building 1 of this embodiment is a steel frame building, and is a building having a multi-layer hierarchy. Moreover, in the following description, the multi-layer building 1 is a three-story structure, and in particular, a structure in which the reinforcing body of the present invention is provided on the second floor part will be described as an example.

  As shown in FIGS. 1 and 2, the multi-layer building 1 has a ramen structure formed using H-shaped steel, a column 2 extending in the vertical direction, and a horizontal direction constructed between the columns 2. Each floor (layer) is constituted by the beam 4 extending in the direction.

  As shown in FIG. 1 (b), each floor in the multi-layer building 1 is a partition arranged along the crossing direction (Y direction of the multi-layer building) and the beam direction perpendicular to the crossing direction (X direction of the multi-layer building). The body 6 is divided into a plurality of regions.

  In the reinforcing method of the present invention, as shown in FIG. 1, a reinforcing body 10 is vertically arranged between upper and lower beams 4 at an arbitrary position between columns 2 of a multi-layer building 1 that is an existing steel building described above. By doing so, while reducing the stress at the beam-column joint of the existing steel building, the rigidity is increased and the displacement with respect to vibration is greatly reduced.

  As shown in FIG. 2, the reinforcing body 10 is configured by connecting a pair of reinforcing members 11 and 12 arranged in series in the vertical direction via a connecting portion 15 with a predetermined gap t. As shown in FIG. 3, the reinforcing members 11 and 12 are preferably made of H-shaped steel composed of a base body 10a and side bodies 10c having flange surfaces 10b on both sides of the base body 10a. This H-shaped steel is arranged so as to act in the strong axis direction. Specifically, as shown in FIG. 1B, the H-shaped steel is arranged so that the flange surface 10b faces the column 2 direction of the multi-layer building 1. The

  The connecting portion 15 is provided on the first connecting portion 16 provided on the left and right sides (flange surface 10b) of the reinforcing members 11 and 12, and on the front and rear sides (or both sides) of the base body 10a of the reinforcing members 11 and 12. A second connecting portion 17.

  The first connecting portion 16 is disposed on the flange surface 10b of the reinforcing members 11 and 12 and connects both the reinforcing members 11 and 12, as shown in FIG. In order to avoid receiving an axial force, the cushioning material 21 (for example, formed in a plate shape) indicated by a hatched portion in FIG. 2 is arranged so as to be superimposed on one reinforcing member side (reinforcing member 12 in FIG. 2). And an auxiliary plate 22 having substantially the same thickness as the cushioning material 21 disposed so as to overlap the other reinforcing member side (reinforcing member 11 in FIG. 2). The main plate 23 (the connecting body of the present application) that connects the buffer material 21 and the auxiliary plate 22 is provided. The main plate 23 is fixed to the reinforcing members 11 and 12 by a fixture 24 such as a bolt and nut, and the buffer material 21 and the auxiliary plate 22 are sandwiched between the main plate 12 and the reinforcing members 11 and 12. The

  Further, the first connecting portion 16 has, for example, guide means 27 for moving one reinforcing member 12 in the vertical direction with respect to the other reinforcing member 11 when the column 2 or the beam 4 is deformed in an earthquake or the like. Is provided. The guide means 27 includes a long hole 26a formed in the main plate 23 and the cushioning material 21 and extending in the vertical direction, and a protrusion 28 inserted into the long hole 26a. The protrusion 28 is provided so as to protrude from the flange surface 10b of one reinforcing member 12 by welding or the like.

  Further, as shown in FIG. 4, the projection 28 is inserted and arranged in the substantially central portion of the long hole 26 a when the main plate 23 is attached.

  In the event of an earthquake, the protrusion 28 moves in the long hole 26a, whereby the reinforcing member 12 is guided in the vertical direction with respect to the reinforcing member 11, and buckling due to the moving of the reinforcing members 11, 12 in the horizontal direction occurs. To prevent.

  As shown in FIG. 2, the second connecting portion 17 is disposed on the surface of the base body 10 a of the reinforcing members 11 and 12 (or both the front and back surfaces of the base body 10 a) to connect both the reinforcing members 11 and 12. It connects and is provided with the substantially plate-shaped connection body 26. Further, on one side of the reinforcing member (reinforcing member 12 in FIG. 2), as shown in FIGS. 2 and 3, the axial force is not provided between the connecting body 26 and the reinforcing member 12. A cushioning material 21 (for example, an elastic member made of rubber or the like formed in a plate shape) indicated by a hatched portion is provided. As shown in FIG. 2, the connecting body 26 is fixed to the reinforcing members 11 and 12 by a fixture such as a bolt and nut.

  Further, as shown in FIGS. 2 and 6, the reinforcing body 10 has the ends of the reinforcing members 11, 12 attached to the beams 4, 4 arranged above and below via a plate 40. The plate 40 is attached to the beam 4 by a welding method generally referred to as butt welding, and the plate 40 is fixed to the reinforcing body 10 by a fixture 42 such as a bolt and nut, so that the reinforcing body 10 and the beam are fixed. 4 are connected.

  Further, since the strength of the beam 4 is insufficient due to the provision of the reinforcing body 10, a plate-like reinforcing plate 45 is attached so as to connect the flange surfaces 10b inside the beam 4 and the beam 4 is reinforced. The The reinforcing plate 45 is arranged in a substantially vertical line shape of the plate 40 and is fixed to the beam 4 by welding. Further, if necessary, the reinforcing plate 45 may be fixed so as to overlap the base of the beam 4 between the pair of reinforcing plates 45 provided in parallel by fillet welding.

  Next, an earthquake-proof reinforcement method using the above-described reinforcing body 10 will be described.

  First, regarding the multi-layer building 1 that is an existing steel building, the installer determines the installation position of the reinforcing body 10 in consideration of the opening and the like. Moreover, the reinforcement body 10 is arrange | positioned so that it may act on a strong axis direction using H-shaped steel.

  Next, according to the determined installation position, the wall surface is cut out to expose the beams 4 and 4 extending in the horizontal direction above and below the hierarchy, and the wall surface on which the reinforcing body 10 is to be installed.

  Next, as shown in FIG. 2, a plate 40 for fixing the reinforcing body 10 to the beam 4 is fixed to the outer upper portion of the beam 4 by welding, and a reinforcing plate 45 that reinforces the beam 4 is provided inside the beam 4. Attach to.

  Next, the reinforcing body 10 composed of the first and second reinforcing members 11 and 12 connected by the connecting body 15 is fixed to the upper and lower sides of the beams 4 and 4 using the fixtures 42 via the plates 40. Is done.

  Finally, the column base is returned to its original position using a mortar or the like, the wall surface treatment is performed, and the installation process of the reinforcing body 10 is finished.

  As described above, the seismic reinforcement structure in the multi-layer building 1 of the present embodiment attaches the reinforcement body 10 to the upper and lower beams 4 of the existing multi-layer building 1 in the vertical direction. A pair of reinforcing members 11, 12 that are arranged in parallel to the vertically extending pillars 2 constituting the multi-layer building 1 and are attached to the beam 4, and a connecting body 23 that connects the reinforcing members 11, 12 in series. The elastic body 21 is interposed between the connecting member 23 and the one reinforcing member 12 side.

  According to the seismic reinforcement structure configured in this way, the rigidity can be increased while reducing the stress at the beam-column joint of the existing steel building, so the displacement against vibration can be greatly reduced, It is possible to easily increase the safety of multi-story buildings against earthquakes with a simple configuration.

  In addition, the reinforcing body 10 used in the seismic reinforcing structure of the present embodiment is provided when there is no room for large braces between the columns when increasing the rigidity of the floor that is vulnerable to deformation when performing seismic reinforcement having a plurality of floors. It is particularly effective. In addition, in the case of reinforcement with braces, the frame rigidity of this reinforcement part becomes extremely high, and it is considered that stress increases from directly under the related pillar to the foundation, causing a large load locally. Since the reinforcing body of the embodiment does not bear an axial force due to its structure, the basic structure model is not changed and the above-described problem does not occur.

  And the reinforcement body 10 of this embodiment fixes and inserts up and down between the large beams which comprise each floor, and is the distance between the fulcrum of a large beam arrange | positioned up and down the floor with a large deformation amount (between a large beam and a reinforcement body). By reducing the distance and the distance between the reinforcing bodies, the rigidity of these beams can be easily increased, and the amount of deformation of the layer including the reinforcing body 10 and the layers above and below the reinforcing body 10 can also be reduced. At the same time, the stress is distributed to the joints on both sides of the reinforcing body 10, and the seismic strength can be increased while reducing the stress of each member that is affected by the insertion of the studs.

  Further, by using such a reinforcing body 10, it is possible to tackle seismic reinforcement design without requiring a particularly advanced investigation or the like with the most general structural calculation method.

  In addition, unlike general braces, it can be installed almost freely, and can be reinforced according to the seismic target by balancing the number and location of installation locations.

  In addition, this embodiment is one form and is not limited to this form. For example, the steel member used in the multilayer building 1 of the present embodiment uses a steel frame generally referred to as H steel, but other forms may be substituted. In this embodiment, as the guide means, the projection 28 moves through the long hole 26a formed in the vertical direction. However, the guide means is not particularly limited to this form, and generally known guide means are used. Can be applied. In the present embodiment, the protrusion 28 is provided on one reinforcing member 12, but may be provided on the other reinforcing member 11.

  In the present embodiment, the multi-layer building 1 has been described as an example. However, the multi-layer building 1 is not necessarily a multi-layer building and may be a one-story building.

  Moreover, when attaching the reinforcement body 10 of this embodiment to the 1st floor part, a chemical anchor etc. is embedded in the concrete material which functions as a beam, and what is necessary is to compensate for the lack of strength below that by attaching the reinforcement body 10. .

DESCRIPTION OF SYMBOLS 1 Multi-story building 2 Pillar 4 Beam 10 Reinforcement bodies 11 and 12 Reinforcement member 21 Elastic body 23 Main plate 40 Plate 45 Reinforcement plate

Claims (4)

A seismic reinforcement structure for an existing steel building that is fixed and attached to the upper and lower beams of the existing steel building,
The reinforcement is
A pair of reinforcing members disposed in parallel to the vertically extending columns constituting the existing steel building and attached to the beam;
A connecting body for connecting the reinforcing members in series,
On one side of the reinforcing member, an elastic body is interposed between the connecting body and the seismic reinforcing structure in the existing steel building. The pair of reinforcing members are connected by a connecting body with a gap,
The earthquake-resistant reinforcing structure in an existing steel building according to claim 1, further comprising guide means for moving the other reinforcing member in the vertical direction with respect to the one reinforcing member. It is a seismic strengthening method for existing steel buildings that fixes and attaches reinforcements to the upper and lower beams of existing steel buildings,
The reinforcing body composed of a pair of reinforcing members connected in series by a connecting body is fixed to the beam via a plate, and the flange surfaces of the H-shaped steel forming the beam are connected by a reinforcing plate. Seismic reinforcement construction method characterized by doing. Reinforcing body used for seismic reinforcing structure in existing steel building, fixing and attaching the reinforcing body to the upper and lower beams of the existing steel building,
The reinforcement is
A pair of reinforcing members disposed in parallel to the vertically extending columns constituting the existing steel building and attached to the beam;
A connecting body connecting the reinforcing members in series,
A reinforcing body characterized in that an elastic body is interposed between the one reinforcing member side and the connecting body.

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