Fundamentals of Direct Displacement-Based Seismic Design and Assessment

Abstract

This chapter presents the fundamentals of the new seismic design method known as direct displacement based design. It is a simple design approach where the multi-degree-of-freedom structure is characterized the secant stiffness and equivalent elastic damping of an equivalent single-degree-of-freedom structure. Design is based on achieving a specified displacement limit state — defined either by material strain limits or non-structural drift limits — under the design level seismic intensity, rather than using these limits merely as upper bounds of acceptable behaviour. The characterization of the structure by secant stiffness avoids the many problems inherent in force-based design where initial stiffness is used to determine an elastic period, and forces are distributed between members in proportion to elastic stiffness.

Copyright © “Displacement-Based Seismic Design of Structures”, authored by M.J.N. Priestley, G.M. Calvi and M.J. Kowalsky, and published in May 2007 by IUSS Press.