JPH09221853A - Earthquake energy absorbing structure of building - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the earthquake energy absorbing effect without narrowing opening parts of the periphery of a steel structure building. SOLUTION: In this earthquake energy absorbing structure, each energy absorbing member 5, which is extended in the vertical direction along a pillar 1 and of which upper and lower ends are connected to an upper and a lower beams 2 by fastening members, is provided at each position near a right and a left pillars 11 of each opening part 3 surrounded by a right and a left pillars 1 and an upper and a lower beams 2. The energy absorbing member 5 is made of a band-shaped metal plate formed along the surface of the opening part 3, and outline of a side edge thereof in the cross direction is set so that the bending stress at the time of plastic deformation in any cross section in the height direction is maintained nearly constant.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a seismic energy absorption structure of a steel structure building, which is capable of enhancing the seismic energy absorption effect without narrowing the outer peripheral opening so much.

[0002]

2. Description of the Related Art Incorporating a member that absorbs input energy during an earthquake into a steel structure can reduce the response to an earthquake input and improve seismic performance. Conventionally, the energy absorption member is installed so as to close the core (opening) of the building to absorb the seismic energy.

[0003]

However, if such an energy absorbing member is installed in the opening surrounded by columns and beams on the outer periphery of the building, the opening will be lost or narrowed. There was a problem that an effective energy absorption effect could not be achieved if an attempt was made to secure a certain amount of opening.

In view of the above circumstances, the present invention mainly provides a seismic energy absorption structure for a steel structure building, which is capable of enhancing the seismic energy absorption effect without narrowing the outer peripheral opening so much. With the goal.

[0005]

According to a first aspect of the present invention, there is provided a seismic energy absorption structure for a building, in which an opening surrounded by left and right columns and upper and lower beams is provided in the vicinity of the left and right columns along the respective columns. An energy absorbing member is provided that extends in the vertical direction and has upper and lower ends joined to the upper and lower beams by fastening members, and the energy absorbing member is made of a strip-shaped metal plate along the surface of the opening.
It is characterized in that the contour of the side edge in the width direction is set so that the bending stress at the time of plastic deformation in an arbitrary cross section in the height direction becomes substantially constant.

According to a second aspect of the present invention, in the first aspect, the contour of the side edge of the energy absorbing member on the column side is formed in a straight line, and the contour of the side edge on the opposite side is the straight line at the center in the height direction. A parabolic shape that is formed in a vertically symmetrical curved line that is recessed to the side, and that the curved line secures a predetermined width required for shear stress transmission between the straight line and the straight line at the center in the height direction, and is convex outward at the upper and lower sides. It is characterized by doing.

[0007]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a front view of a building 10 to which an embodiment of the present invention is applied, and FIG. 2 is a plan view of the building 10.
This building 10 is a steel structure building of a frame structure in which a frame is constructed with columns 1 and beams 2, and a rectangular opening surrounded by columns 1 and 1 on the left and right and beams 2 and 2 on the upper and lower sides is provided on the outer periphery of each floor. It has many parts 3.

Energy absorbing members 5 extending in the up-down direction are arranged along the columns 1 and 1 in the vicinity of the side faces of the columns 1 and 1 on the left and right sides that form the inner peripheral edge of each opening 3. These energy absorbing members 5 are made of strip-shaped steel plates (metal plates) along the surface of each opening 3, and the upper and lower ends are the upper and lower beams 2,
2 (the bottom end is the foundation beam 2a) is joined with bolts or rivets (fastening members).

FIG. 3 is a configuration diagram of the energy absorbing member 5, and FIG. 4 is an enlarged view of a portion where the energy absorbing member 5 is installed. The energy absorbing member 5 has a vertically symmetrical shape, has flange portions 5a and 5a for bolting to the beam 2 at the upper and lower ends, and has an energy absorbing region 5b at an intermediate portion thereof. It is provided. The flange portions 5a, 5a are set to the maximum width, and the region 5b for energy absorption is set to be narrower than that.
Then, in the region 5b for absorbing energy, the contour 5c of the side edge in the width direction, so that the bending stress in the horizontal direction at the time of plastic deformation in an arbitrary cross section in the height direction becomes substantially constant,
5d is set.

Specifically, as shown in FIG. 3, the contour of the side edge 5c of the energy absorbing member 5 on the column side is formed in a straight line, and the opposite side (the side facing the center of the opening 3) side. Edge 5
The contour of d is formed in a vertically symmetrical curve that is recessed toward the straight line side at the center in the height direction. Further, the curved line secures a predetermined width S necessary for transmitting shear stress between the straight line at the recessed portion 5e at the center in the height direction, and has a parabolic shape convex outward at the upper and lower sides thereof. The parabolic region 5f is a range in which the stress state is uniform during plastic deformation. Further, an appropriate R (curve) is given to the central recessed portion 5e and the connecting portion between the region 5f and the flange 5a so that stress is not concentrated.

The energy absorbing member 5 having such a structure
Are arranged along the pillar 1 and have flanges 5 at the upper and lower ends.
a and 5a are fastened to the steel brackets 6 and 6 provided on the upper and lower beams 2 and 2 with bolts via joint plates 7 and 7, respectively. The beam 2 is made of H-shaped steel, and a reinforcing rib 8 is attached between the upper and lower flanges of the beam 2.

In this building 10, since the energy absorbing member 5 is installed in each opening 3 as described above, when each layer of the building 10 is horizontally deformed during an earthquake, the energy absorbing member 5 made of each steel plate is promptly released. It bends and yields to absorb seismic energy. At that time, the energy absorption efficiency is high because the substantially entire cross section in the height direction of the energy absorbing member 5 is plasticized. Further, since it is only connected to the beam 2 with bolts, it can be easily replaced if it is damaged excessively.

Particularly, in the case of this energy absorbing member 5,
Due to its high energy absorption efficiency, it can be compactly housed near the pillars on the outer periphery in buildings where it is difficult to incorporate conventional energy absorbing members (for example, pure ramen structure etc.), and the opening 3 is made narrower. Never. Further, since a compact housing can be realized, a large number can be installed, and the energy absorption performance of the entire building can be adjusted by increasing or decreasing the number.

[0014]

As described above, according to the invention of claim 1, in the vicinity of the left and right columns of the opening surrounded by the left and right columns and the upper and lower beams, the columns extend vertically along the columns and the upper and lower ends Is provided with an energy absorbing member that is joined to the upper and lower beams with fastening members, and this energy absorbing member is composed of a strip-shaped metal plate along the surface of the opening, and plastic deformation at any cross section in the height direction. Since the contours of the side edges in the width direction are set so that the bending stress during bending is almost constant, when each layer of the building is horizontally deformed during an earthquake, the energy absorbing member will bend and yield early, thereby contributing to the seismic energy. Can be absorbed. At that time, since the substantially entire cross section in the height direction of the energy absorbing member is plasticized, the energy absorbing efficiency is high and a large seismic energy can be absorbed. Also, since the energy absorption efficiency of each energy absorption member is high,
It can be compactly housed near the pillars on the outer periphery of the building, and the strength at the time of an earthquake can be increased without making the opening on the outer periphery of the building narrow. Further, since it can be housed compactly, it can be installed from a small opening to a large opening, and the energy absorption performance of the entire building can be adjusted by increasing or decreasing the total number of installations.

Further, by setting the shape of the energy absorbing member as in the invention of claim 2, the effect of claim 1 can be reliably brought out.

[Brief description of drawings]

FIG. 1 is a front view of an entire building to which an embodiment of the present invention is applied.

FIG. 2 is a plan view of the entire building to which the embodiment of the present invention is applied.

FIG. 3 shows an energy absorbing member used in the embodiment of the present invention, (a) is a front view and (b) is a side view.

FIG. 4 is a partially enlarged view of the embodiment of the present invention.

[Explanation of symbols]

 1 Pillar 2 Beam 3 Opening 5 Energy absorbing member 5c, 5d Side edge 10 Building

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI Technical display location F16F 15/02 8312-3J F16F 15/02 K

Claims (2)

[Claims] 1. Energy that extends in the vertical direction along each pillar and has upper and lower ends joined to the upper and lower beams by fastening members in the vicinity of the left and right pillars in an opening surrounded by the left and right pillars and the upper and lower beams. An absorbing member is provided, and the energy absorbing member is made of a strip-shaped metal plate along the surface of the opening so that the bending stress at the time of plastic deformation in an arbitrary cross section in the height direction becomes substantially constant, Seismic energy absorption structure for buildings, characterized in that the contours of the side edges in the width direction are set. 2. The contour of the side edge of the energy absorbing member on the side of the column is formed in a straight line, and the contour of the side edge on the opposite side is formed in a vertically symmetrical curve that is recessed toward the straight side at the center in the height direction. And a predetermined width required for shear stress transmission between the curved line and the straight line at the center in the height direction, and a parabolic shape that is convex outward at the upper and lower sides thereof. Item 1. The seismic energy absorption structure of the building according to item 1.