This grant is made under "Expedited Awards for Novel Research" to explore the feasibility of using metallic tubes as cyclic energy dissipators in building frames to dissipate most of the energy associated with severe lateral loading conditions. An experimental and an analytical phase will be included. During the experimental phase of this research, scale model frames will be prepared and subjected to cyclic loading conditions. The frames and energy dissipating tubes will be instrumented with strain gages to measure levels of strains as functions of time. The primary objective of the frame experiments will be to track the yielding and energy dissipation characteristics of the metallic tubes when they are attached to frames subjected to lateral loading conditions. The goal will be to develop structural framing systems possessing the following two characteristics: 1) Yielding/energy dissipation occurs in the tubes long before any plastic deformations are initiated in the primary structural members of the frame. 2) Yielding the energy dissipating tubes is not accompanied by a significant reduction in lateral stiffness of the frame. The analytical phase of this task will involve the development and verification of computer software (ABAQUS) to predict the dynamic response of frames equipped with tubular energy dissipators under cyclic loading. If feasible, a structural arrangement could result in load carrying main structural members remaining in the elastic ranges, thereby eliminating major damage from occurring to the building.
