Report - PEER - University of California, Berkeley

A PRAGMATIC APPROACH FOR PERFORMANCE-BASED SEISMICDESIGNMark ASCHHEIM 1ABSTRACTA practical design approach that achieves a subset of the potential goals of performance-basedearthquake engineering is described. The design approach integrates a number of recentdevelopments and interprets fundamental observations from non-traditional perspectives. Theshift in perspective—from a focus on period of vibration to a focus on yield displacement—allows simple and direct approaches to be used to limit peak displacement and system ductilitydemands to acceptable values. A required base shear strength is determined for use inpreliminary design, maintaining consistency with current design practice. Nonlinear dynamicanalyses are used for performance assessment and refinement of the design.Keywords: Displacement-based design procedures; Yield displacement.1. INTRODUCTIONThe need to limit damage in moderate earthquakes has motivated research inperformance-based earthquake engineering (PBEE) for over a decade. Substantialprogress continues to be made in simulation capabilities, modeling of componentresponse, and refinement of performance specifications. Multiple performanceobjectives (e.g., SEAOC, 1995) are routinely contemplated and the feasibility ofdisplacement-based design approaches (e.g., Moehle, 1992) is accepted. However,current practice is far from achieving the potential of PBEE. A simple procedure ispresented herein that addresses a subset of the response parameters of interest. Theapproach is effective for limiting roof drift and system ductility to arbitrary limitsassociated with one or multiple performance objectives (e.g., Sullivan et al., 2003)and produces a base shear for use in design, maintaining consistency with currentdesign practice. The focus is on the lateral response of regular multistory buildingsthat can be represented by planar (2D) elements, that are not sensitive to P-Deltaeffects, and which are being designed at displacements well below their collapsevalues.1 Associate Professor, Department of Civil Engineering, Santa Clara University, 500 El Camino Real,Santa Clara, CA 95050; maschheim@scu.edu481