SECONDARY STIFFNESS DEVICES FOR STRUCTURAL SYSTEMS

In 2017, the National Oceanic and Atmospheric Administration reported over $300B in structural damages caused by natural disasters. Various devices exist to prevent structural damage after seismic events by absorbing load displacements. One such device, a buckling restrained brace (BRB), absorbs energy through plastic deformation and utilizes a stiff sleeve with a metal shell to prevent buckling under compressive forces. The sleeve is prone to fracturing and excessive plastic deformation can cause permanent damage to the system.

The proposed system limits displacement of steel beams during a natural disaster and reduces structural damage by adding addition stiffness to BRBs through reinforced steel sleeves. Steel compression plates attached at the joint where a steel beam connects to the ground and at the steel tube encasing mortar add stability to the system. Secondary tension straps decrease excessive deformation improving the reliability of the system.