JP3451327B2 - Unbonded steel brace stiffened with steel pipe - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is used as a seismic element of the beam-column Frames in Steel or steel reinforced concrete building, it has been the seat屈補Tsuyoshi in steel pipe Unbond Related to steel frame braces. [0004] Conventionally, various shapes as seismic elements Hashiraharika configuration, brace structure is employed. Especially, in recent years prevents buckling of steel braces, unbonded steel braces frequently that stiffen the steel braces seat屈補Tsuyoshizai the purpose of increasing the reduction with plastic deformation capacity of <br/> Frames of steel weight It was started. For example, Japanese Unexamined Patent Publications Nos. 64-80641 and 5-44254 disclose that a steel pipe is filled with concrete and a separation layer (or unbonding) is formed between the steel pipe and the friction pipe to prevent friction between the two. An unbonded brace sharing the role (function) of concrete is described. Japanese Unexamined Patent Publication (Kokai) No. 2-101238 discloses an unbonded steel brace in which the outer periphery of a steel material having a rectangular or cylindrical cross section is covered with a buckling stiffener made of reinforced concrete in a rectangular shape. Japanese Unexamined Patent Publication No. Hei 4-30046 describes an unbonded steel frame brace in which a cross section of a steel frame material having a cross shape is covered with a buckling stiffener made of reinforced concrete in a rectangular shape. Japanese Patent Application Laid-Open No. 5-113054 discloses an unbonded steel frame brace in which the outer periphery of a flat steel material is stiffened with concrete. JP-A-6-33
No. 511 discloses an unbonded steel frame brace in which the outer periphery of an H-section steel is stiffened with rectangular reinforced concrete. At present, unbonded braces are mainly made of flat steel, and are used for hotel door walls and the like. However, the flat steel brace has a limit in the amount of axial force that can be borne, and it is impossible to share a larger axial force. Therefore, recently, an unbonded steel frame brace using a relatively large H-shaped steel as a main material has been adopted to make up for the above-mentioned disadvantage. [0005] As described above, in the conventional unbonded steel brace, a structure in which the outer periphery of the steel brace is stiffened with reinforced concrete occupies the mainstream. The work of assembling (or arranging reinforcement), assembling the formwork, placing concrete, etc. is complicated, it takes time and effort to manufacture, and it is heavy, so it is inconvenient to transport and handle, etc. There were disadvantages. Also, if cracks occur in the reinforced concrete as a buckling stiffener, the bending stiffness is reduced to about 1/5 and the stiffening effect is lost. Therefore, care must be taken to prevent dry shrinkage cracks and to handle them carefully. It was troublesome to pay attention. Accordingly, an object of the present invention is to provide an unbonded steel frame brace stiffened with a steel pipe, which is easy to manufacture and relatively lightweight, has excellent quality and workability, and has good buckling and stiffness. is there. [0007] As a means for solving the above problems, an unbonded steel brace stiffened by a steel pipe according to the first aspect of the present invention is an H-shaped steel bearing an axial force.
The outer periphery of the more composed steel brace, a circle with a diameter that generally circumscribes
Shaped steel, Yes and cover the Ku outside contact state where loose as a seat屈補Tsuyoshizai, that at least one portion of the substantially central portion of the steel pipe is fastened so as not falling down by steel braces and shift bolt Features. [0008] [0009] [action] horizontal input such as an earthquake to be loaded into Hashiraharika configuration, the axis force of the steel brace 1 (axial compression stress, the axial tensile stress) only treated as, as a seat屈補Tsuyoshizai No power is transmitted to the steel pipe 2. When the steel braces 1 exhibit a buckling behavior due to an excessive axial compressive force, the steel braces 1 and the steel pipe 2
At the point of contact, the steel brace 1 is stiffened by the strong restraining force of the steel pipe 2 to prevent buckling and exhibit large proof stress and high plastic deformation capacity. Incidentally, an H-shaped steel having a size of 100 × 100 × 6 × 8 mm and a length of more than 1600 mm was used as a steel frame brace and had a diameter of 152.
FIG. 4A is a graph showing the relationship between the horizontal force and the interlayer displacement angle when a load test was performed on a test specimen stiffened with a steel pipe having a thickness of 4 mm, a thickness of 4.5 mm, and a length of more than 1500 mm. A loading test was conducted on a test specimen stiffened with reinforced concrete having a square shape with a side of 180 mm on one side, and the horizontal force-interlaminar displacement angle relationship was shown in the graph of FIG. 4B. It is evident that the stiffening capacity with respect to is approximately equal and sufficiently large. Since the steel pipe 2 is fixed to the steel frame brace 1, it does not slip over (inadvertently). Next, an embodiment of the present invention shown in the drawings will be described.
Figure 1 and Figure 2 shows the unbonded steel brace according to a first embodiment of the present invention, FIG. 3 shows an example of applying the brace of the building to Column Frames <br/>. This unbonded steel frame brace has a size of 300 × 300 × 12 × 25 as a main material.
A round steel pipe 2 having a diameter of 450 mm and a thickness of 6 mm is loosely covered as a buckling stiffener on an outer periphery of a H-shaped steel 1 having a diameter of 4 mm. Of the H-shaped steel 1 is fixed to the H-shaped steel 1 with a stopper bolt 3 that penetrates the web of the H-shaped steel 1 at a right angle.
Both end portions projecting from the steel pipe 2 of the H-shaped steel 1 is processed into the joint 1a of the Hashiraharika structure <br/>. [0012] unbonded steel braces stiffen in the above steel tube, as shown in FIG. 3, in the plane of Frames formed by steel column 4 and the steel beam 5 of the building, the H-beams 1 flange bending Arrangement of bearing direction (strong axis) (beam steel web and H-beam 1
As the web is oriented parallel), each web bolting both ends of the H-beams 1 and the bonding member 6 and the rack joining member 7 of the structure in the corner of the beam center portion, the flange is placed incorporated by welding ing. However, the mode of use as a brace is not limited to that of FIG. FIG. 5 shows a steel brace 1 made of a square steel pipe covered with a circular steel pipe 2 having a diameter almost circumscribed as a buckling stiffener. FIG. 6 shows a steel brace 1 made of a cruciform steel frame covered with a circular steel pipe 2 having a diameter almost circumscribed as a buckling stiffener. FIG. 7 shows a steel brace 1 made of a cruciform steel frame covered with a square steel pipe 2 having a diameter substantially circumscribed in a diagonal direction as a buckling stiffener. FIG. 8 shows a square steel pipe 2 as a buckling stiffener that is substantially circumscribed in relation to the outer periphery of a steel frame brace 1 made of a square steel pipe, which is rotated by 45 °. FIG. 9 shows a steel brace 1 made of an I-shaped steel covered with a circular steel pipe 2 having a substantially circumscribed diameter as a buckling stiffener. FIG. 10 shows a steel pipe 2 having a flat shape such that edges of both ends of the flat steel are circumscribed as a buckling stiffener on the outer periphery of a steel frame brace 1 made of a flat steel plate. Although not shown in any of the embodiments, at least one portion of the steel pipe is fixed to the steel frame brace. As described above with reference to the various embodiments, the present invention implements the cross-sectional shapes of the steel braces and the steel pipes based on combinations of steel materials and steel pipes of various shapes or deformation applications apparent to those skilled in the art. be able to. The unbonded steel brace stiffened with the steel pipe according to the present invention has a simple structure composed of a combination of the steel brace 1 and the steel pipe 2 and is simply covered with the steel pipe. Thus, it is possible to reduce costs and to provide a product excellent in both quality and reliability. In addition, since the weight can be reduced, the workability is remarkably improved.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a front view showing a first embodiment of the present invention. FIG. 2 is a side view of FIG. 3 is an elevational view showing an application example to Hashiraharika structure. FIG. 4A is a graph showing the relationship between the horizontal force and the interlayer displacement angle of an unbonded steel brace stiffened with conventional general reinforced concrete, and FIG. made dimensionless in yield load P _y corresponding to yield the axial force, and the compression side is positive. R on the horizontal axis corresponds to the rotation angle of the column. FIG. 5 is a side view showing a different embodiment of the present invention. FIG. 6 is a side view showing a different embodiment of the present invention. FIG. 7 is a side view showing a different embodiment of the present invention. FIG. 8 is a side view showing a different embodiment of the present invention. FIG. 9 is a side view showing a different embodiment of the present invention. FIG. 10 is a side view showing a different embodiment of the present invention. [Description of Signs] 1 Steel frame brace (H-section steel) 2 Steel pipe 3 Non-slip bolt

──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Naoki Suzuki 4-1-1, Honcho, Chuo-ku, Osaka-shi Inside the Osaka Main Store of Takenaka Corporation (72) Inventor Yasuo Higashibata 1-5-5 Otsuka, Inzai-cho, Inba-gun, Inba-gun, Chiba (56) References JP-A-4-149345 (JP, A) JP-A-4-70438 (JP, A) JP-A-5-3402 (JP, U) (58) ) Surveyed field (Int.Cl. ⁷ , DB name) E04B 1 / 16,1 / 18,1 / 24,1 / 58 E04H 9/02

Claims (1)

(57) on the outer periphery of the Claims 1] Steel Brace consisting H-beam to bear an axial force, a circular steel tube with a diameter that is substantially circumscribes, Ku outer contact state where loose as a seat屈補Tsuyoshizai Over the middle of the steel pipe
At least one of the central parts has a steel brace and
Characterized in that it is secured so as not falling down by belt, unbonded steel braces stiffen in the steel pipe.