New analysis and design procedures have been developed for the perform
ance-based seismic rehabilitation of buildings. Such procedures requir
e accurate estimates to be made of displacements, velocities, and acce
lerations. Nonlinear response-history analysis of single-degree-of-fre
edom oscillators, having varying values of yield strength and post-yie
ld stiffness and using 20 velocity-scaled earthquake ground motions, w
as undertaken to verify the accuracy of the proposed displacement-esti
mation procedures that make use of relations between inelastic and ela
stic displacements. Neat-field earthquake records were not considered.
The assumption that mean inelastic displacements are approximately eq
ual to mean elastic displacements is reasonable for oscillators with s
trength ratios greater than 0.20 and elastic periods greater than the
characteristic site period. For other values of the strength ratio and
elastic period, the assumption is nonconservative. Mean-plus-one-stan
dard-deviation inelastic displacements are approximately equal to 1.5
times mean inelastic displacements for elastic periods greater than 0.
3 s.