چكيده فارسي :
Seismic excitations are one of the most hazardous loadings encountered during the life time of
structures. Seismic evaluation of Steel Moment Frames, which are used often as lateral seismic system
subjected to earthquake must account for the structural steel parameter and workmanship uncertainties, is of
high importance.
In this study, the uncertainties ,which involve the quality of workmanship (quality of construction and weld
fabrication) that is affected in the behavior of the beam-to-column connectionsas well as mechanical
properties such as Young modulus and yield-strength, are parameters for considering those associated with
structural steel framing parameters. Incremental dynamic analysis is utilized to assess the structural dynamic
behavior of the frames and to generate the required data for performance based evaluations.
A probabilistic framework for seismic assessment of a structural system,which takes into account the
uncertainty in the mentioned variables, is used to examine the variation of the probability of exceeding a
limit state capacity under seismic excitations. In this study, seismic evaluation of structure has been
accomplished in two modes, before construction (the designed structure with no uncertainty) and after
construction (the structure with uncertainty). This confidence level is assesable and obtaianble through
evaluation of the factored demand-to-capacity, namely DCFD format. SMF at the IO performance level, as
affected by uncertainties, shows few changs in DCFD values as well as in confidence level in
comparisonwith the structure with no uncertaintywhile, at CP, result shows more changes, increase ofthe
DCFD parameter and consequently decrease of confidense levelof the structue affected by unertainrties.
