TITLE 
Capacity spectrum method for seismic
design of a building 
INTRODUCTION 
The capacity spectrum method is a
practical method to evaluate building responses under earthquakes. Input
earthquake ground motion is defined by a response spectrum. Since both force
and deformation are important for nonlinear analysis, the spectrum is plotted
in acceleration vs. displacement domain which is termed as a demand spectrum.
Seismic performance of a building is examined by nonlinear pushover analysis
using a certain distribution for horizontal static loads. The relationship
between base shear force and top displacement is plotted in acceleration vs.
displacement domain which is termed as a capacity curve. The response
of the building is then obtained as a crossing point between the demand
spectrum and the capacity curve.

USAGE MANUAL 
See Reference 1). 
EXAMPLE 
See Reference 1). 
REFERENCE 
1)
ATC 40 “Seismic evaluation and retrofit of concrete buildings”, ATC, 1996 
