JPH10110470A - Length adjustment type buckling constrained unbonded brace - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a length adjustment type buckling constrained unbonded brace capable of adjusting increase and decrease of overall length of a center axial force member within a certain range, reducing a manufacturing cost by standardization, absorbing faults in accuracy of construction to load accurately and adjusting accuracy of construction of steel frames. SOLUTION: A center axial force member 2 is continuously provided to first joint sections 2a and 2a, it is constituted of a main axis section 2b having overall length surrounded by a steel pipe concrete member 1, a first screw axis section 2c projected from the steel pipe concrete member 1, a turn buckling section 2d screwing the first screw axis section 2c therein from one end thereof, a second screw axis section 2e screwed in from the other end of the turn buckling section 2d and a second joint section 2f continuously provided to the second screw axis section 2e. Then, cross sectional area S2 of a length adustment section constituted of the first screw axis section 2c, turn buckling section 2d and second screw axis section 2e is set larger than cross sectional area S of the main axis section 2b.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a buckling-restrained unbonded brace used as a structural element for resisting horizontal forces such as seismic force and wind force in various building structures such as houses and low-rise buildings.

[0002]

2. Description of the Related Art As disclosed in Japanese Utility Model Laid-Open Publication No. 63-101603, a steel central axial force member is inserted into a buckling restraining steel tubular concrete member, and the surface of the central axial force member and the steel tubular concrete member are disposed. A buckling-restrained unbonded brace in which an unbonded material coating for preventing adhesion is provided between the two is already known.

In the brace constructed as described above, the buckling of the central axial force member is prevented by the steel tubular concrete member, and the application of the axial force to the steel tubular concrete member is prevented by the unbonded material coating. It functions as a highly reliable bracing member in any of the compressive forces.

[0004] However, in the conventional buckling-restrained unbonded brace, the joint to the building structure is provided continuously at both ends of the central axial force member, and the distance between the joints is limited to the target building structure. It is designed to correspond to the dimension between the mounting parts. For this reason, it is impossible to use a brace manufactured for a specific building structure for another building structure with different dimensions between mounting parts, and it is possible to reduce the manufacturing cost of buckling-restrained unbonded braces by standardization. Did not.

Further, it is inevitable that an error occurs between a design dimension and an actual building dimension in a building structure, and when this error is large, a bolt hole in a joint fitting on the building structure side and a buckling. It may be difficult to align the joint of the restrained unbonded brace with the bolt hole, and it may not be possible to mount it on a building structure. In such a case, it is necessary to replace the fittings and change the position of the bolt hole, so that the work efficiency of the brace mounting process is deteriorated.

[0006]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to be able to reduce or increase the overall length of a central axial force member within a certain range, so that it has versatility and can reduce brace manufacturing cost by standardization. It is another object of the present invention to provide a length-adjustable buckling unbonded brace that can be attached to a building structure accurately by absorbing a deviation in the building accuracy and that can adjust the building accuracy of the building.

[0007]

Means for Solving the Problems In a length-adjustable buckling unbonded brace of the present invention, an unbonded material coating 3 is applied to a buckling-restraining steel tubular concrete member 1 to form a central axial force member 2.
Is inserted. The central axial force member 2 is connected to the first joint 2a joined to the building structure and the first joint 2a,
Main shaft part 2b whose entire length is surrounded by steel pipe concrete member 1
A first screw shaft portion 2c connected to the main shaft portion 2b and protruding from the steel pipe concrete member 1, a turnbuckle portion 2d into which the first screw shaft portion 2c is screwed from one end, and a turnbuckle portion 2d. It is composed of a second screw shaft portion 2e screwed from the other end and a second joint portion 2f connected to the second screw shaft portion 2e and joined to the building structure. The cross-sectional area S _{2 of the} length adjusting portion constituted by the first screw shaft portion 2c, the turnbuckle portion 2d, and the second screw shaft portion 2e.
Is set larger than the cross-sectional area S ₁ of the main shaft portion 2b.

In use, the first joint portion 2a of the central axial force member 2 is connected to the joint fitting 10 on the upper beam 9 side of the building structure 8.
And the second joint portion 2f is joined to the joint fitting 13 on the lower beam 12 side by the bolt 14. When the position of the bolt hole 6 of the second joint 2f and the position of the bolt hole on the joint fitting 13 do not match due to the deviation of the construction accuracy, the turnbuckle 2d is rotated to operate the first screw shaft with respect to the turnbuckle 2d. 2c and second screw shaft 2
The screwing depth of e is increased or decreased, and the entire length of the central axial force member 2 is adjusted to expand or contract.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In the illustrated embodiment, a concrete steel pipe member 1 is composed of a round steel pipe 1a and concrete (cement mortar) 1b filled therein.
The main shaft portion 2b and the first screw shaft portion 2c of the central axial force member 2 are integrally formed of a round steel material, and the first joint portion 2 is made of a steel plate.
a is connected to the main shaft 2b by welding. The base end of the first joint 2a enters one end of the steel pipe concrete member 1, and a bolt hole 4 is provided at the end. The base end portion of the first screw shaft portion 2c enters the other end of the steel pipe concrete member 1.

The cross-sectional area S _{3 of the base} portion of the first joint 7
And the cross-sectional area S ₄ of the base end portion of the first screw shaft portion 2c is set to be larger than the cross-sectional area S ₁ of the main shaft portion 2b in order to prevent buckling at the entry end portion (S ₄ =
S _s ). A deformation absorbing elastic material 5 made of styrene foam or the like is fixed to an entry end face of each of the first joining portion 2a and the first screw shaft portion 2c with an adhesive or the like.

The movement of the entire steel pipe concrete member 1 to shift in the longitudinal direction of the central axial force member 2 is caused by the first joint 2
a and the main shaft 2b, and between the first screw shaft 2c and the main shaft 2a. The unbonded material coating 3 made of a mold release agent for concrete molding, oil paint, asphalt, etc. is applied not only to the surface of the main shaft portion 2b but also to the surface of the entry portion of the first joint portion 2a and the first screw shaft portion 2c. It has been subjected. The unbonded material coating 3 prevents the central axial force member 2 from adhering to the concrete portion 1b of the steel tubular concrete member 1, so that no axial force from the central axial force member 2 is applied to the steel tubular concrete member 1. ing.

The second joint portion 2f made of a steel plate is connected to the base end portion of the second screw shaft portion 2e made of a round steel material by welding, and a bolt hole 6 is provided at the tip end portion of the second joint portion 2f. The inner peripheral surface of each end of the turnbuckle portion 2d made of a round steel pipe is provided with a female screw in a left-right opposite direction, and a hexagonal cross-sectional portion 7 into which a rotary operation tool is fitted is provided at an intermediate portion of the turnbuckle portion 2d. Is provided. A turnbuckle part 2d is provided on the outer peripheral surface of the first screw shaft part 2c and the second screw shaft part 2e.
Male threads are cut corresponding to each female thread.

The sectional shape of the steel pipe 1 is not limited to a circle, but may be another sectional shape such as a square. Further, the constituent material of the central axial force member 2 is not limited to a round steel material,
It can also be composed of a steel plate or the like. The main shaft portion 2b and the first screw shaft portion 2c are not limited to being formed of an integral material, but those manufactured separately can be used in combination. Female screw holes are provided for the first screw shaft portion 2c and the second screw shaft portion 2e,
A male screw can also be cut on the outer peripheral surface of the turnbuckle 2d.

[0014]

As described above, in the buckling restrained unbonded brace of the present invention, the first screw with respect to the turnbuckle portion 2d is rotated by rotating the turnbuckle portion 2d of the central axial force member 1 in the forward or reverse direction. Since the screwing depth of the shaft portion 2c and the second screw shaft portion 2e is increased or decreased, the entire length of the central axial force member 2 is adjusted to expand and contract. Therefore, even if there is some error in the construction accuracy of the building structure, the error can be reliably absorbed and the work structure can be mounted between required parts of the building structure with good workability.

In addition, since it has a length adjusting function and has versatility that can be applied to various frames having different dimensions within the adjustment range, standardization of braces is possible, and production costs due to mass production are reduced. Savings are possible.

Further, in the buckling-restrained unbonded brace of the present invention, the length adjusting portion formed by the first screw shaft portion 2c, the turnbuckle portion 2d, and the second screw shaft portion 2e is adjacent to the second joint portion 2f. The arrangement is such that the moment is small, and the occurrence of buckling in the length adjusting portion is prevented. Further, since the cross-sectional area S ₂ of said length adjusting portion is set larger than the cross-sectional area S ₁ of the main shaft portion 2b, the center axis force member 2 will be surrendered only the main shaft portion 2b, the length adjustment The part is preserved without surrender.

Furthermore, the buckling-restrained unbonded brace of the present invention having the above-described structure uses one piece even in a place where two pieces are conventionally used in an X shape in order to prevent buckling. Is sufficient, and the energy absorption capacity is large.

[Brief description of the drawings]

FIG. 1 is a schematic front view of a building structure equipped with a length-adjustable buckling-restrained unbonded brace according to one embodiment of the present invention.

FIG. 2 is an enlarged longitudinal sectional view of a main part of the buckling restrained unbonded brace.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Buckling restraint steel pipe concrete member 2 Central axial force member 2a First joint 2b Main shaft 2c First screw shaft 2d Turnbuckle 2e Second screw shaft 2f Second joint 3 Unbonded material coating 4 Bolt hole 5 Elastic material for deformation absorption 6 Bolt hole 7 Hexagonal cross section 8 Building structure 9 Upper floor beam 10 Joint bracket 11 Joint bolt 12 Lower beam 13 Joint bracket 14 Joint bolt

Claims (1)

[Claims] 1. A buckling-restraining steel tubular concrete member 1 is coated with an unbonded material coating 3, and a central axial force member 2 is inserted therethrough.
A first joint portion 2a joined to the building structure, a main shaft portion 2b connected to the first joint portion 2a and surrounded by the steel pipe concrete member 1, and a main shaft portion 2b;
, A first screw shaft portion 2c protruding from the steel pipe concrete member 1, a turnbuckle portion 2d into which the first screw shaft portion 2c is screwed from one end, and a turnbuckle portion 2d from the other end. Second screw shaft 2e to be screwed
And a second joint 2f connected to the building structure and connected to the second screw shaft 2e, and configured by a first screw shaft 2c, a turnbuckle 2d, and a second screw shaft 2e. length adjusting unit cross-sectional area S ₂ of the length adjustment type buckling restraint Unbonded brace set larger than the cross-sectional area S ₁ of the main shaft portion 2b of being.