equivalent sdof models for probabilistic performance assessment of multistory buildings: methodology and application for steel special momentframes

The paper proposes a methodology for generating equivalent single-degree-of-freedom (eqsdof) models that can mimic the response of multistory buildings from the linear-elastic range through collapse in a probabilistic context. the use of an sdof model as a surrogate for multistory buildings can significantly alleviate the high computational cost for probabilistic assessment of seismic response considering both model uncertainty and record-to-record variability. to showcase the proposed methodology, the eqsdof model is developed for special steel moment frame (smf) buildings. the properties of the eqsdof model representing a multi-degree-of-freedom (mdof) structure are computed using a probabilistic function of the fundamental period of the structure developed using bayesian linear regression. to validate the proposed model, the response of a multistory building is compared with that of the corresponding eqsdof model. the results show that the proposed eqsdof model captures the behavior of the mdof structure up to collapse with acceptable accuracy in response statistics and 95% reduction in analyses runtime.