Inertial force-limiting anchorage system for seismic resistant building structures

An innovative floor anchorage system is under development for seismic-resistant buildings. The anchorage possesses a predefined "cut-off" load to limit inertial forces, transforming seismic demands into relative displacement of the floor system with respect to the primary vertical elements, and dissipating seismic energy in the building system. Elastic restoring, stabilizing, and re-centering elements complete the inertial force-limiting anchorage system (IFAS). The system has the potential to limit diaphragm forces, thereby lowering floor accelerations and reducing seismic demands on the lateral force resisting system, resulting in less damage to the structure, non-structural elements and building contents. The IFAS concept is being developed in a multi-university research project including meetings with design consultants for prototype development, computational simulation to optimize design parameters, full-scale component testing to determine prototype characteristics, and a half-scale shake table test to demonstrate the concept. This paper summarizes these efforts to date.