A damping mechanism for damping energy resulting from a lateral force on a structure may include a first portion, a second portion configured for longitudinal motion relative to the first portion, a primary energy absorption system configured for frictionally coupling the first portion and the second portion and converting motion of the second portion relative to the first portion into heat energy, and a secondary energy absorption system configured to absorb energy through non-linear deformation and provide a self-centering effect on the damping mechanism.

A control structure comprising a pivotably based rocker frame assembly integral with rotary yield units able to produce a constant resistive yield force through high elasto-plastic displacements and high ductilities. Located within and distributed about the rotary yield units are flexural yield plates with particular boundary conditions enabling them to elasto-plastically flex to high cycling elasto-plastic displacements and high displacement and curvature ductilities, while maintaining a constant resistive yield force. The constant resistive yield force produced by the replaceable rotary units enables the control structure to resist and endure extreme seismic events (base motion input) with a constant resistive yield force, while plastic curvatures within the yield zones of the flexural plates of the rotary units are maintained well within their capacity; and forces within the control structure, within its supporting foundations, and within masses or other structures it is seismically supportive of are controlled and limited.

An energy absorbing structure includes a base, a loading platform, a pair of side supports, a center support, and a pair of flexible segments. The loading platform is spaced apart from the base. The side supports project from the base toward the loading platform. The center support projects from the loading platform toward the base. The flexible segments extend from the side supports to the center support and connect the side supports to the center support. The flexible segments have straight edges and curved surfaces disposed between the straight edges. The straight edges extend from the side supports to the center support and are oriented at an oblique angle relative to the base. Each of the curved surfaces faces one of the base and the loading platform.

A structural assembly and a structural bracing system including the structural assembly are presented. The structural assembly includes Belleville disks and shape memory alloy (SMA) rods with nonlinear elastic behavior (e.g., Nitinol rods) to resist lateral force. Stacked Belleville disks are placed between plates resulting in nonlinear elastic behavior in compression. Shape memory alloy rods are placed at the corners of the plates and held by nuts at the exterior faces of the plates. The rods are loose when a compression load is applied to the plates and will work in tension when a tensile load is applied to the plates. A shaft (e.g., steel tube) is placed at the center of the Belleville disks to stabilize the assembly. Addition of the assembly with nonlinear elastic behavior in both tension and compression loadings to a structural bracing system improves the structural behavior of the bracing system.

A friction damper for attenuating vibrations of a structure. The friction damper includes a first connecting member configured to be attached to a first member of the structure, a second connecting member configured to be attached to a second member of the structure, a first slotted-bar interconnected between the first connecting member and the second connecting member, and a second slotted-bar interconnected between the first connecting member and the second connecting member. The first slotted-bar and the second-slotted bar are configured to allow horizontal and vertical movements of the first connecting member and the second connecting member relative to each other responsive to vibration of the structure.

A lateral bracing system is disclosed for affixing a column to a beam in a construction. The lateral bracing system includes a pair of buckling restraint plates, one each affixed to a top and bottom flange of a beam. The lateral bracing system further includes at least one yield plate for each buckling restraint plate. Each yield plate includes a first end affixed to the column, and a second end affixed to the beam.

The present invention relates to a damping system that utilizes a space between an inner building and a stair chamber installed outside the inner building to control vibration of an earthquake applied to a building or a building structure, and more particularly, to a damping system utilizing a space between a stair chamber and an inner building, which is installed in a building structure including the inner building and the stair chamber to damp a transverse force due to seismic waves.

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.

Precast construction elements are described suitable for use in high seismic area. 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 control structure comprising a pivotably based rocker frame assembly integral with rotary yield units able to produce a constant resistive yield force through high elasto-plastic displacements and high ductilities. Located within and distributed about the rotary yield units are flexural yield plates with particular boundary conditions enabling them to elasto-plastically flex to high cycling elasto-plastic displacements and high displacement and curvature ductilities, while maintaining a constant resistive yield force. The constant resistive yield force produced by the replaceable rotary units enables the control structure to resist and endure extreme seismic events (base motion input) with a constant resistive yield force, while plastic curvatures within the yield zones of the flexural plates of the rotary units are maintained well within their capacity; and forces within the control structure, within its supporting foundations, and within masses or other structures it is seismically supportive of are controlled and limited.