JPH05133136A - Beam built-in type earthquake-proof damper part for steel frame large beam - Google Patents

Abstract

PURPOSE:To increase plasticizing region of an earthquake-proof damper part in the early level of the input of earthquake motion and to increase energy absorbing ability of the earthquake-proof damper part at a lost cost. CONSTITUTION:A steel damper 5 spans between webs 2a and 2a of a steel frame beam member end parts 3 and 3 and comprises a plate-form part 6 positioned at right angles with the web and a mounting seat part 7 positioned at the end part of the plate-form part 6 and fixed to the web. A portion 8 between the mounting parts wherein out-of-plane bending is apt to occur is provided between the mounting seat parts.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vibration control damper section for a large beam made of steel aggregate.

[0002]

2. Description of the Related Art Conventionally, as shown in FIG. 6, in a seismic damper section 1 for a girder of a steel frame structure, a pair of steel girder members 2, 2 constituting the girder a are incorporated as a girder.
Are arranged so as to abut each other at the center of the girder a, and the steel dampers 4 are attached and fixed to both sides of the web 2a of the girder member so as to extend over the ends 3 and 3 of the adjacent girder members.

As shown in FIG. 8, the steel damper 4 is in the form of a plate made of a substantially H-shaped steel material, and both sides of the mounting surface portion 40 are bolted to the web 2a of the steel girder member 2 as described above. And a continuous portion 41 having a narrowed center by connecting the mounting surface portions 40.

[0004]

However, regarding the steel frame structure adopting the seismic damper part having the above-mentioned structure, when the steel material damper is examined at the early level of the seismic motion input (elastic design area), the plasticizing area becomes small. ,
Therefore, there is a drawback that the energy absorption capacity is low. In addition, since the substantially H-shaped steel damper is cut out from the steel plate, the cost is high in terms of workability and yield.

In view of the above-mentioned circumstances, the present invention has an object to increase the plasticized region of the seismic damper at an early level of seismic motion input, and to reduce the energy absorption capacity of the seismic damper at low cost. The purpose is to raise.

[0006]

The present invention has been made in consideration of the above problems, and a pair of steel frame girder members forming a girder are arranged so as to abut at the center of the girder. In a damping damper part of a steel girder provided with a steel damper over the adjacent ends of the steel damper, the steel damper extends from one web at the end of the steel girder member to the other web and at a right angle to the web. Providing a beam built-in type vibration control damper part in a steel girder characterized in that it comprises a plate-shaped portion positioned as a position and a mounting seat portion that is fixed to the web at the end of the plate-shaped portion, The above problem is to be solved.

[0007]

In the present invention, the plate-shaped portion between the mounting seats of the steel damper is not a portion directly supported but a portion where out-of-plane bending is likely to occur. For this reason, when energy is transmitted to the plate-shaped part between the mounting seats at an early level of seismic motion input, energy is easily received at this part and plastic deformation occurs, thus improving the energy absorption capacity of the seismic damper. To do.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will now be described in detail with reference to the embodiments shown in FIGS. In the present invention, the seismic control damper portion 1 is of a beam built-in type as shown in the drawing, and the steel material dampers 5 are provided in the longitudinal direction of both sides of the girder a. This steel damper 5 is, as shown in FIG. 3, a plate-shaped portion 6 extending across the webs 2a, 2a of the steel frame girder end portions 3, 3 and a steel frame girder member located at the end portion of the plate-shaped portion 6. The mounting seat portion 7 is provided at the end portion 3 so as to face the web 2a. As shown in FIG. 2, each of the mounting seat portions 7 sandwiches the web 2a from both sides. The plate portion 6 is provided so as to be positioned at a right angle to the web 2a by being bolted to, that is, so as to project laterally from the web surface.

As described above, the plate-shaped portion 6 of the steel damper 5 is in a state in which its end is supported by the web 2a via the mounting seat 7, and between the mounting seats of the plate-shaped portion 6. 8
Is provided as a part that is not directly supported. Therefore, out-of-plane bending is likely to occur between the mounting seat portions 8,
The plasticizing region is wide and the energy absorption capacity is high at the early level of seismic input.

For example, as shown in FIG. 4, the space between the mounting seats 8 of the plate-like portion 7 can be considered as a plate having both ends fixed and a constant width W (see a in FIG. 4). In the stress distribution when deformed (the deformed shape is shown in FIG. 4B), the plate end side reaches the plasticized region (the portion reaching the plasticized region in C of FIG. 4 is indicated by the arrow b).
).

Further, the space 8 between the mounting seats in the plate-shaped portion 7 may be formed by cutting out the outer edge side. As shown in FIG. 5, in this case, it can be considered as an outer edge bow-shaped plate with both ends fixed so that the width W ′ of the portion corresponding to the end portion of the steel frame is minimized (see FIG. 5B). In the stress distribution when deformed by the application of energy (the deformed shape is shown in Fig. 5B), the entire region reaches the plasticized region (the portion reaching the plasticized region in C of Fig. 5 is indicated by the arrow b). It shows an extremely high energy absorption capacity.

In the vibration damping damper section 1 having the above structure,
The energy transmitted to the plate-shaped portion 6 at an early level of the seismic motion input makes it easy for the mounting seat space 8 to reach a shape deformation that is a plastic deformation, and the energy absorption capacity is enhanced.

[0013]

As described above, according to the present invention,
A pair of steel girder members forming a girder are arranged so as to abut each other at the center of the girder, and a steel damper is provided in the seismic damper part of the steel girder over the end portion of the steel girder member, the steel material The damper extends from one web at the end of the steel girder member to the other web and is fixed to the web at a plate-like portion positioned at a right angle to the web and at the end of the plate-like portion. Since it consists of the mounting seat, out-of-plane bending of the plate part of the steel damper can be effectively used, and at the early level of earthquake motion input, the steel part such as the plate part of the steel damper is expected to yield and the energy absorption capability is expected. A high damper part can be obtained. In addition, the shape is easier, the yield is better, and the degree of processing is smaller than that of the conventional plate-shaped steel damper that is surface-bonded to a large beam. It has a practical effect.

[Brief description of drawings]

FIG. 1 is an explanatory view showing an embodiment of a beam built-in type vibration control damper part in a steel frame large girder according to the present invention.

FIG. 2 is an explanatory diagram showing a cross section taken along the line AA of FIG.

FIG. 3 is an explanatory diagram showing a cross section taken along the line BB in FIG.

FIG. 4 is an explanatory view showing a space between the mounting seat portions of the plate-like portion in one embodiment, (a) shows a plate shape, (b) shows a deformed state, and (c) shows a stress distribution. is there.

5A and 5B are explanatory views showing a space between mounting seat portions of a plate-shaped portion in another embodiment, in which (A) shows a plate shape, (B) shows a deformed state, and (C) shows a stress distribution. Is.

FIG. 6 is an explanatory diagram showing a conventional example.

7 is an explanatory diagram showing a cross section taken along line C-c of FIG.

FIG. 8 is an explanatory view showing a steel damper in a conventional example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Seismic damper part 2 ... Steel girder member 2a ... Web a ... Girder 3 ... End part of steel girder member 5 ... Steel damper 6 ... Plate part 7 ... Mounting seat 8 ... Between mounting seats

Claims (1)

[Claims] 1. A seismic damper for a steel girder in which a pair of steel girder members forming a girder are arranged so as to abut each other at the center of the girder, and a steel damper is provided over the end portion of the steel girder member close to each other. In the section, the steel damper extends from one web of the steel girder member end portion to the other web, and a plate-shaped portion positioned at a right angle to the web, and located at the end portion of the plate-shaped portion. A beam built-in type vibration control damper part for a steel beam, comprising a mounting seat part fixed to a web.