Low cost, light weight, energy-absorbing earthquake brace

Abstract

An energy absorbing seismic brace for both retrofit and new construction. The brace comprises a central strut of either multi-legged or homogeneous section fabricated from low strength aluminum, whose characteristics maximize the seismic energy absorption for a building installation. This central strut absorbs energy at high weight-specific levels by virtue of the hysteresis in its load-deflection relationship. In order to eliminate the possibility of buckling of the energy absorbing strut when it passes through the compression portion of a load cycle, it is surrounded by a system of spacers and an external sleeve providing very high bending rigidity at low weight. The spacers may be fabricated from low-density foams, pseudo-concrete, fibrous composites, or metals, depending upon the application. The outer sleeve may also be fabricated from a variety of materials, depending upon whether the embodiment calls for the principal bending rigidity to be provided by the spacers or sleeve.

Dependencies are inferred from the claim text.