This Phase I SBIR project deals with structural/mechanical devices that improve the performance or reduce the cost of earthquake resistant structures. These devices, such as dampers, isolators, energy dissipators and active controls, use materials and technology that are quite new and untried. Their long term endurance, maintenance requirements, and practical applicability have as yet to be demonstrated. A special device that is completely within the state of the art of standard structural steel construction will be developed. It consists of a specialized connector called the "sequential connector" that admits an initial, limited and repeated zero resistance slip under loading. A structural element, connected by means of the sequential connector to a lateral force resisting system, will augment the resistance of the system without a corresponding increase in its response frequency. This unique property produces a response to seismic excitation that is significantly lower than the displacement response if a standard connection is used. The successful development and application of this innovation will significantly reduce the cost of earthquake mitigation and improve the performance of steel buildings.
