Method, apparatus, and systems are disclosed for damping the movements of structures undergoing dynamic forces. The disclosed dampers are a new type of steel plate dampers, intended to reduce the cost and improve the performance of structures subject to severe seismic loading. While in these dampers the metal plates undergo plastic deformation as a method of absorbing and dissipating energy, the disclosed designs do not allow the stress and strain in the metal plates to go above a predetermined design value and; therefore, the new dampers have long lives and do not need repair or replacement after a big earthquake or similar events. These dampers may be used for building and non-building structures. In such applications the required damping capacities are relatively high and different scales of sliding force and stroke are required.

A prestress-free self-centering energy-dissipative tension-only brace, including a self-centering mechanism, an energy dissipation mechanism, a force-limiting energy-dissipative mechanism, a high strength steel cable, and a sleeve. The self-centering mechanism includes a sliding end plate, a spring, and a connection rod. One end of the spring is connected and fixed to the inner wall of the sleeve, and the other end of the spring is connected with the sliding end plate. One end of the connection rod is anchored at the center of the sliding end plate, and the other end of the connection rod passes through a fixed end of the spring. The energy dissipation mechanism includes rotating shafts, rotating wheels, friction plates, chains, and a cross-shaped connecting piece.

The buckling-restrained brace that is capable of being fixed to connected portions of a structure using bolts, the brace includes: a plate member extending in an axial direction, and in which bolt holes for fixing the bolts are formed at end portions of the plate member in the axial direction; and a buckling-restrained member configured to restrain a center portion of the plate member in the axial direction to prevent the plate member from buckling, wherein the buckling-restrained member includes a pipe member surrounding the plate member from the outside in a radial direction, and a filler filling the gap between the pipe member and the plate member, and the plate member includes a fixing plate, a portion of which is embedded in the filler, and the remaining portion is protruded from the filler in the axial direction, and in which the bolt hole is formed at an end portion of the remaining portion in the axial direction.

An earthquake resistant and reinforcing device for buildings and bridges is provided. In this device, two support mandrels are disposed on two ends of a main tube, and one ends of the two support mandrels are inserted in to the main tube. Baffle plates are disposed near the ends of the two support mandrels in the main tube, and sheath covers are disposed at the ends of the two support mandrels outside the main tube. A first elastic part is disposed in the main tube and between the baffle plates of the two support mandrels. A second and a third elastic parts are respectively disposed between the baffle plates of the support mandrels and the sheath covers. This device can be installed between beams and columns of buildings and bridges for effectively absorbing the energy waves acting thereon and thus increase the safety of the buildings and bridges.

A structural yielding link, particularly for use in an eccentrically braced frame arrangement or in a linked column frame arrangement having a first end having a means for connecting to a face of a first beam and a second end having a means for connecting to a face of a second beam; a first variable cross-section portion and a second variable cross-section portion extending from the first end and from the second end, respectively; and a constant cross-section portion joining the first variable cross-section portion and the second variable cross-section portion.

A beam coupler adapted to couple two beams mounted side by side. One coupler comprises a central plate mounted to the first beam, comprising two central-plate side faces in the coupling orientation; and a longitudinal oblong hole providing a passage connecting the two side faces. The coupler also comprises a pair of side plates mounted to the second beam, each comprising an interior face to neighbor the central plate; an exterior face; and a circular side-plate hole providing a passage connecting the interior face with the exterior face. The coupler further comprises compression means applying an inward preload over the plates, comprising a body extending between the exterior faces through the circular and oblong holes. The oblong holes allow displacement of the body of the compression means therein in the longitudinal direction upon a displacement of the plates resulting from a deflection of the beams.

A shrinkage compensating device for seismic restraint in wood building construction combines a spring-operated take-up device (TUD) with a ratcheting split nut. The split nut, attached to or formed as part of a rotatable component of the TUD, acts as the securing nut for the TUD and allows the TUD with the split nut to be slipped over the top of a threaded rod and pulled down along the rod into place against a structural member. Several forms of attachment of the split nut to the spring-operated TUD are disclosed, as is a simplified rotatable split nut version.

Precast construction elements are described suitable for use in high seismic areas. The precast construction elements can be precast, pre-topped double tees. The precast construction elements incorporate a passive energy dissipation device in a flange. The energy dissipation device provides a ductile connection having a deformation capacity of larger than 0.6″. Adjacent elements are connected to one another at joints that include the passive energy dissipation device. Passive energy dissipation devices can be passive hysteretic dampeners, such as U-shaped flexural plates. Passive energy dissipation devices can be bar dissipaters (e.g., grooved dissipaters). Also described are passive hysteretic dampers that include U-shaped flexural plates held in conjunction with a reinforcement element that defines a circle around which the flexural plate can bend.

A lateral bracing system having high initial stiffness and including yield links capable of effectively dissipating stresses generated within the lateral bracing system under lateral loads.

A member-to-member planar connection bracket that includes multiple repeated fuse element configurations that each provide a pre-determined inelastic load-carrying capacity and a reliable inelastic deformation capacity upon development of one or more inelastic hinge locations within the fuse elements. The fuse configurations are interconnected in series such that the total deformation accommodated between first end of the bracket and second end of the bracket is the sum of deformations accommodated by the individual fuse configurations. Multiple brackets are configured in laminar configurations and interconnected to create a connection assembly that provides increased strength or increased deformation capacity as compared to an individual bracket. The connection assembly is used to connect a first structural member and second structural member. The pre-determined maximum inelastic load-carrying capacity of the assembly is less than the elastic load-carrying capacity of the first structural member and the second structural member.