Performance-Based Design as a Strategy for Risk Reduction: Application to Seismic Risk Assessment of Composite Steel-Concrete Frames

Performance-based design is an efficient strategy for assessing and reducing the risk that a construction violates some performance requirement. In this paper, a procedure for performance-based assessment of seismic risk is illustrated with reference to a composite steel-concrete frame structure. Such risk is conventionally evaluated in a simplified formulation, i.e. as the mean annual frequency of exceeding a threshold level of damage in any significant structural element. The procedure is applied to evaluate the site seismic hazard, the structural damage, the corresponding capacity, and finally the seismic risk of a plane frame, extrapolated from a 3-D structure that was subjected to experimental tests at the ELSA-JRC Laboratory in Ispra, Italy. Specific attention is given to the choice of the intensity and damage measures for use in performance-based seismic risk assessment of composite steel-concrete frames.