Claims
- 1. A buckling restrained brace 1 wherein a steel-made center axial member (3) is passed through a buckling-constraining concrete member (2) reinforced with a steel member (6), and an adhesion-preventive film (4) is provided to the interface between the steel-made center axial member (3) and buckling-constraining concrete (5),
the adhesion-preventive film (4) showing a secant modulus in the thickness direction of at least 0.1 N/mm2 between a point which shows a compressive strain of 0% and a point which shows a compressive strain of 50%, and up to 21,000 N/mm2 between a point which shows a compressive strain of 50% and a point which shows a compressive strain of 75%, and having a thickness (dt) in the plate thickness direction of the steel-made center axial member (3) and a thickness (dw) in the plate width direction thereof from at least 0.5 to 10% of the plate thickness (t) and from at least 0.5 to 10% of the plate width (w), respectively.
- 2. A buckling restrained brace according to claim 1, wherein the steel-made center axial member (3) is a steel material showing a 0.2% proof stress or a yield point stress of up to 130 N/mm2.
- 3. A buckling restrained brace according to claim 1, wherein the steel-made center axial member (3) is a steel material showing a 0.2% proof stress or a yield point stress of 130 to 245 N/mm2.
- 4. A buckling restrained brace according to claim 1, wherein the steel-made center axial member (3) has a minimum cross-sectional area in a central portion (21) in the longitudinal direction having a restricted length ratio which is the ratio of the length of the central portion (21) to the whole length, and the steel-made center axial member has a cross-sectional area larger than the minimum cross-sectional area of the central portion (21) in the longitudinal direction, at both ends (22, 23) in the longitudinal direction connectively provided to the central portion (21) in the longitudinal direction.
- 5. A buckling restrained brace according to claim 4, wherein the steel-made center axial member (3) shows an axial equivalent stiffness of at least 1.5 times that of the steel-made center axial member (3) in any one of claims 1 to 3 which have same-sectional area from one end to the other end, passing through the central portion (21) in the length direction of said member (3).
- 6. A buckling restrained brace according to claim 1, wherein each of the cross-sectional areas (22-1, 23-1) at both ends (22, 23) in the longitudinal direction of the steel-made center axial member (3) which is obtained by subtracting a through hole-formed deficient area of the corresponding through holes (26) for bolt insertion passing is at least 1.2 times the cross-sectional area (21-1) of the central portion (21) in the longitudinal direction of the steel-made center axial member (3).
- 7. A buckling restrained brace according to claim 1, wherein the steel member (6) is a reinforcing bar (6-1).
- 8. A buckling restrained brace according to claim 1, wherein a lid (24) is fixed to at least one end of the buckling-constraining concrete member (2).
- 9. A buckling restrained brace according to claim 1, wherein a slip stopper (25) is provided to the center of the steel-made center axial member (3).
- 10. A buckling restrained brace according to claim 1, wherein the buckling restrained brace (1) having the steel-made center axial member (3) which is provided with through holes (26) for bolt insertion passing at both ends (22, 23), and steel-made connecting plates (27) are friction jointed with high tension bolts by clamping, while the friction face sides at both ends (22, 23) of the steel-made center axial member (3) which are contacted with the respective friction face sides of the steel-made connecting plates (27) or the friction face sides of the steel-made connecting plates (27) which are contacted with the respective friction face sides at both ends (22, 23) of the steel-made center axial member are made to have a higher surface hardness and a higher surface roughness than the counterpart friction face sides.
- 11. A buckling restrained brace according to claim 1, wherein at least one set comprising three layers which are formed from a C-shaped cross-sectional inside steel plate (29), a visco-elastic sheet (30) and a C-shaped cross-sectional outside steel plate (31) is fastened to each of the sides of the buckling-constraining concrete member (2) of the buckling restrained brace (1),
one end (32) of the C-shaped cross-sectional inside steel plate (29) is fastened to one end (34) of the buckling restrained brace (1), and the other end (33) of the C-shaped cross-sectional outside steel plate (31) is fastened to the other end (35) of the buckling restrained brace (1) in the direction opposite to the one end (32) of the C-shaped cross-sectional outside steel plate (29).
- 12. A damping steel structure (38) wherein the buckling restrained braces (1) according to claim 1 or 4 are placed in the damping steel structure (38) which is formed with columns (36) and beams (37) prepared from a steel material showing a yield point stress higher than that of the steel-made center axial members (3) of the buckling restrained braces (1),
the buckling restrained braces (1) showing both elastic and plastic behavior when the damping steel structure (38) vibrates under vibration action, and the damping steel structure (38) which is formed with the columns and the beams, showing elastic behavior.
Priority Claims (3)
Number |
Date |
Country |
Kind |
11-186384 |
Jun 1999 |
JP |
|
11-349175 |
Dec 1999 |
JP |
|
2000-191718 |
Jun 2000 |
JP |
|
CROSS REFERENCE TO RELATED APPLICATION
1. This application is a continuation-in-part application of Ser. No. 09/511,207 filed on Feb. 23, 2000.
Continuation in Parts (1)
|
Number |
Date |
Country |
Parent |
09511207 |
Feb 2000 |
US |
Child |
09735252 |
Dec 2000 |
US |