Fayaz R. Rofooei - department of civil eng sharif university of technology tehran
Mohammad R. Mirjalili - department of civil eng sharif university of technology tehran
nader k.a.attari - department of structural engineering building and housing research center BHRC tehran

nonlinear dynamic procedure NDP can in general lead to more rational results when compared to the nonlinear static procedures NSPs. Consideration of the effect of higher modes and the changes in structural period and inertia load patterns when structural softening occurs are among the main differences of these two approaches. on the other hand most engineers prefer to use NSPs due to the modeling restrictions time consuming calculation, the frequency content of the strong ground motion and other difficulties present in NDP approach.

nonlinear static analysis , pushover analysis , lateral load pattern , nonlinear dynamic analysis