# US 12,180,743 B2 · Buckling-restrained brace and seismic force-resisting structure > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,180,743 B2 - Document ID: US12180743B2 - Status: Granted - Kind: B2 - Application number: 18/007,271 - Filed: 2022-08-10 - Published: 2024-08-08 - Granted: 2024-12-31 - Earliest claimed: 2021-09-08 - Assignees: Nippon Steel Engineering Co., Ltd. - Applicants: Nippon Steel Engineering Co., Ltd. - Inventors: Benjamin Jacob Sitler; Masao Terashima; Toru Takeuchi; Yuki Terazawa; Ryota Matsui - Web page: https://patentgrep.com/patent/US12180743B2 ## CPC - E04H 9/0237: {Structural braces with damping devices} - E04B 1/58: of bar-shaped building elements {(framework connections E04B1/21, E04B1/2403, E04B1/2604)} - E04H 9/02: withstanding earthquake or sinking of ground (foundations E02D27/34) - E04H 9/024: {Structures with steel columns and beams} - F16F 7/00: Vibration-dampers; Shock-absorbers (using fluid F16F5/00, F16F9/00; specific for rotary systems F16F15/10 {; belt tensioners F16H7/12}) - F16F 7/12: using plastic deformation of members {(F16F9/30 takes precedence; yieldable means for mounting bumpers on vehicles B60R19/26; yieldable or collapsible steering columns B62D1/192)} - F16F 15/02: Suppression of vibrations of non-rotating, e.g. reciprocating systems; Suppression of vibrations of rotating systems by use of members not moving with the rotating systems ({F16F15/005 takes precedence } ; layered products B32B; suppression of vibration in ships B63; {relieving load on bearings, using magnetic means F16C39/06}) - F16F 15/04: using elastic means (single elements or their attachment F16F1/00 - F16F13/00); {(F16F15/023, F16F15/03 take precedence)} - E04H: BUILDINGS OR LIKE STRUCTURES FOR PARTICULAR PURPOSES; SWIMMING OR SPLASH BATHS OR POOLS; MASTS; FENCING; TENTS OR CANOPIES, IN GENERAL (foundations E02D) - E04B: GENERAL BUILDING CONSTRUCTIONS; WALLS, e.g. PARTITIONS; ROOFS; FLOORS; CEILINGS; INSULATION OR OTHER PROTECTION OF BUILDINGS (border constructions of opening in walls, floors or ceilings E06B1/00; {electromagnetic shielding H05K9/0001}) - F16F: SPRINGS; SHOCK-ABSORBERS; MEANS FOR DAMPING VIBRATION ## Abstract A buckling-restrained brace includes a core and a restrainer, the core includes a first steel plate having a first yield point, a second steel plate having a second yield point different from the first yield point, and a third steel plate having a third yield point different from the first yield point, the first steel plate is sandwiched between the second steel plate and the third steel plate, and a length of a first yielding segment of the first steel plate in the axial direction is different from a length of the second yielding segment of the second steel plate in the axial direction, and is different from a length of the third yielding segment of the third steel plate in the axial direction. ## Claims ### Claim 1 A buckling-restrained brace, comprising: a core extending in an axial direction; and a restrainer encasing the core from an outer side thereof in a state where both end segments of the core in the axial direction protrude from the restrainer, wherein the core includes a first steel plate having a first yield point, a second steel plate having a second yield point different from the first yield point, and a third steel plate having a third yield point different from the first yield point, the first steel plate being sandwiched between the second steel plate and the third steel plate, the first steel plate includes a first yielding segment provided in a center segment of the first steel plate in the axial direction and having an axial strength smaller than an axial strength of both end segments of the first steel plate in the axial direction, the second steel plate includes a second yielding segment provided in a center segment of the second steel plate in the axial direction and having an axial strength smaller than an axial strength of both end segments of the second steel plate in the axial direction, the third steel plate includes a third yielding segment provided in a center segment of the third steel plate in the axial direction and having an axial strength smaller than an axial strength of both end segments of the third steel plate in the axial direction, and a length of the first yielding segment in the axial direction is different from a length of the second yielding segment in the axial direction, and is different from a length of the third yielding segment in the axial direction. ### Claim 2 (depends on 1) The buckling-restrained brace according to claim 1, wherein: the first yield point is higher than the second yield point, and is higher than the third yield point; and the length of the first yielding segment in the axial direction is longer than the length of the second yielding segment in the axial direction, and is longer than the length of the third yielding segment in the axial direction. ### Claim 3 (depends on 2) The buckling-restrained brace according to claim 2, wherein the length of the first yielding segment in the axial direction is longer than the length of the second yielding segment in the axial direction, and is longer than the length of the third yielding segment in the axial direction such that a ratio of steel plate yield deformations is increased compared with a case where the length of the first yielding segment in the axial direction is the same as the length of the second yielding segment in the axial direction and is the same as the length of the third yielding segment in the axial direction, the ratio of steel plate yield deformations being a ratio of a second yield displacement when an axial load, at which yielding of the first steel plate occurs, is applied to the core to a first yield displacement when an axial load, at which yielding of the second steel plate or the third steel plate occurs, is applied to the core. ### Claim 4 (depends on 2) The buckling-restrained brace according to claim 2, wherein the first steel plate is provided such that the first yielding segment protrudes from the restrainer. ### Claim 5 (depends on 1) The buckling-restrained brace according to claim 1, wherein: the first yield point is lower than the second yield point, and is lower than the third yield point; and the length of the first yielding segment in the axial direction is shorter than the length of the second yielding segment in the axial direction, and is shorter than the length of the third yielding segment in the axial direction. ### Claim 6 (depends on 5) The buckling-restrained brace according to claim 5, wherein the length of the first yielding segment in the axial direction is shorter than the length of the second yielding segment in the axial direction, and is shorter than the length of the third yielding segment in the axial direction such that a ratio of steel plate yield deformations is increased compared with a case where the length of the first yielding segment in the axial direction is the same as the length of the second yielding segment in the axial direction and is the same as the length of the third yielding segment in the axial direction, the ratio of steel plate yield deformations being a ratio of a second yield displacement when an axial load, at which yielding of the second steel plate or the third steel plate occurs, is applied to the core to a first yield displacement when an axial load, at which yielding of the first steel plate occurs, is applied to the core. ### Claim 7 (depends on 5) The buckling-restrained brace according to claim 5, wherein the second steel plate is provided such that the second yielding segment protrudes from the restrainer, and the third steel plate is provided such that the third yielding segment protrudes from the restrainer. ### Claim 8 (depends on 1) The buckling-restrained brace according to claim 1, wherein the first yielding segment has a width smaller than a width of both end segments of the first steel plate in the axial direction, the second yielding segment has a width smaller than a width of both end segments of the second steel plate in the axial direction, and the third yielding segment has a width smaller than a width of both end segments of the third steel plate in the axial direction. ### Claim 9 (depends on 1) The buckling-restrained brace according to claim 1, further comprising connectors which are provided to both end segments of the core, wherein each of the connectors includes a first connection segment connected to the first steel plate, a second connection segment connected to the second steel plate, and a third connection segment connected to the third steel plate. ### Claim 10 (depends on 2) The buckling-restrained brace according to claim 2, further comprising connectors which are provided to both end segments of the core, wherein each of the connectors includes a first connection segment connected to the first steel plate, a second connection segment connected to the second steel plate, and a third connection segment connected to the third steel plate, wherein the second connection segment and the third connection segment are located closer to a center in the axial direction than the first connection segment. ### Claim 11 (depends on 5) The buckling-restrained brace according to claim 5, further comprising connectors which are provided to both end segments of the core, wherein each of the connectors includes a first connection segment connected to the first steel plate, a second connection segment connected to the second steel plate, and a third connection segment connected to the third steel plate, wherein the first connection segment is located closer to a center in the axial direction than the second connection segment and the third connection segment. ### Claim 12 (depends on 9) The buckling-restrained brace according to claim 9, wherein the first connection segment is provided so as not to overlap the second connection segment in the axial direction, and is provided so as not to overlap the third connection segment in the axial direction. ### Claim 13 (depends on 9) The buckling-restrained brace according to claim 9, wherein each of the connectors includes a pair of connection plates sandwiching the first steel plate, the second steel plate, and the third steel plate in a direction intersecting a thickness direction of the first steel plate. ### Claim 14 (depends on 1) The buckling-restrained brace according to claim 1, wherein: the second yield point is the same as the third yield point; and the length of the second yielding segment in the axial direction is the same as the length of the third yielding segment in the axial direction. ### Claim 15 (depends on 1) The buckling-restrained brace according to claim 1, wherein the second steel plate and the third steel plate are symmetric in a thickness direction of the first steel plate, with respect to the thickness-center of the first steel plate in the thickness direction of the first steel plate. ### Claim 16 (depends on 1) The buckling-restrained brace according to claim 1, wherein the first steel plate, the second steel plate, and the third steel plate are arranged parallel to each other. ### Claim 17 (depends on 1) The buckling-restrained brace according to claim 1, further comprising a spacer provided between the second steel plate and the third steel plate. ### Claim 18 (depends on 1) A seismic force-resisting structure, comprising: a frame; a plurality of gusset plates projecting inward from the frame; and the buckling-restrained brace according to claim 1, wherein the buckling-restrained brace spans between the plurality of gusset plates, and both end segments of the core are connected to the plurality of gusset plates using a welded, pinned, or bolted connection.