Seismic Response of Steel Framed Hospital Buildings with Self-Centering Systems (2004-2005)

This paper introduces the concepts of Elasto-Plastic Systems (EPS) and Self-Centering Systems (SCS) for the seismic design of steel-framed hospital buildings. Redesign of the MCEER West Coast Demonstration Hospital with SCS is conducted using this approach. An ensemble of 25 simulated MCEER Ground Motions having a probability of exceedence of 5% in 50 years in Northridge, California is used as earthquake excitations in the seismic analysis of the building. The SCS are achieved by Post-Tensioned Energy-Dissipated (PTED) beam-to-column connections. The redesign procedure is briefly outlined. With a set of optimal design parameters for the SCS, the structural system achieves very good seismic performance. Not only are the maximum displacements reduced, but the floor accelerations are also diminished, which is rarely achieved with other passive hysteretic control systems, such as friction or metallic dampers. Also, residual drifts are largely reduced or eliminated, which will decrease the cost to repair. The improved performance obtained suggests that the implementation of SCS can lead to improved seismic behavior at a reasonable cost.