A strut may be interposed between a first floor plate and a second floor plate of a multi-story building, wherein the first floor plate is disposed overtop of the second floor plate. The strut includes a first post section and a second post section. The first post section includes a first portion that is coaxial with, annular to and slidably disposed within a second portion of the second post section. A damping actuator is interposed between the first post section and the second post section, and is arranged to dynamically control a position of the first post section in relation to the second post section. The strut also includes an accelerometer. A controller is in communication with the accelerometer and the damping actuator, and controls the damping actuator to control the position of the first post section in relation to the second post section.

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.

An eddy current damper includes a screw shaft, first permanent magnets, second permanent magnets, a cylindrical magnet holding member, a cylindrical conductive member, and a ball nut meshing with a screw shaft. The screw shaft is movable in the axial direction. The first permanent magnets are arrayed along the circumferential direction around the screw shaft. The second permanent magnet is arranged between the first permanent magnets, wherein the arrangement of magnet poles is inverted between the second permanent magnet and the first permanent magnet. The magnet holding member holds the first permanent magnet and the second permanent magnet. The conductive member is opposed to the first permanent magnets and the second permanent magnets with a gap therebetween. The ball nut is disposed inside the magnet holding member and the conductive member, and is fixed to the magnet holding member or the conductive member.

A shearwall is disclosed for use in lightweight or other constructions to transmit lateral shear forces and dissipate energy on the construction. In examples, the shearwall includes a central panel formed of wood, and side plates formed of steel. The side plates may be affixed at lower corners of first and second opposed surfaces of the central panel. Each side plate may include a fastening plate for affixing the side plate to the central panel, and a restraint plate which fits within a reduced area section of the central panel between the first and second surfaces.

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 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.

A columnic actuated spring loader can be incorporated into existing structures. The system includes: a base that is positioned on a floor, a vertical column having a proximal end that is secured to the base and a distal end, dual vertical rods having proximal ends that are secured to the base and distal ends, and upper and lower spring mechanisms. The distal ends of the column and rods support an upper bearing plate. Each spring mechanism includes a support member that is slidably secured to the dual vertical rods, dual springs that are slidably attached to the dual rods, and bracing which is a network of rigid members that interconnect the support member, column and dual rods. Loads are transferred from the upper bearing plate and support plates to the base. The energy is dissipated into the foundation. The bracings distribute energy between the dual rods and the column.

A reinforcement structure includes compound trusses placed horizontally symmetrically, and each compound truss is constituted by a first truss and a second truss. Each first truss has: a vertical side; a first inclined side extending obliquely downward from an upper end of the vertical side; and a second inclined side connecting between the vertical side and a lower end of the first inclined side. Each second truss shares the first inclined side with the first truss and has: a horizontal side extending horizontally from the upper end of the vertical side; and a second inclined side connecting between a tip end of the horizontal side and the lower end of the first inclined side. Each compound truss is coupled to the construction in a state where the vertical side is along an inner side surface of the construction and the horizontal side is along a ceiling surface of the construction.

A dissipator for interfacing between the ground and supporting structures, which comprises a supporting base that can be fixed to the ground and supports a contact base that can be associated, by way of kinematic connection elements, with a supporting structure, interface elements being provided between the contact base and the supporting base and being adapted to allow the movement of the contact base with respect to the supporting base at least along two directions that are parallel to the ground, control elements being further provided which act between the supporting base and the contact base and are adapted to control the relative movement between the supporting base and the contact base; the dissipator comprises at least one rod-like dissipation body that acts between the ground and the supporting structure, the rod-like dissipation body having at least partially a behavior of the dissipative type.

Axial buckling restrained braces are provided. In various embodiments, a device comprises a plurality of cylindrical sleeves arranged parallel to each other. Each of the plurality of sleeves has an interior surface defining an interior region. A plastically deformable rod is arranged within the interior region of each of the plurality of sleeves. The plastically deformable rod is adapted to assume a helical shape upon compression.

A multi-load friction damper includes opposed gusset-side plates defining a slip channel. First and second brace-side plates are received within the slip channel and form first and second frictional engagements respectively. The frictional force of the first and second frictional engagements may be different. A multi-layer friction damper includes a central gusset-side plate and first and second outer gusset-side plates. First and second brace-side plates are received between the central gusset-side plates and the first and second outer gusset-side plates to form first, second, third and fourth frictional engagements. A multi-damper assembly includes a gusset engagement member and brace engagement member. A plurality of friction dampers extend between the gusset engagement member and the brace engagement member.