Seismic performance assessment of intermediate moment-resisting steel frames designed based on misidentified site soil classes

This research aims to investigate the extent that an incorrect assumption for soil type may endanger seismic safety of moment-resisting steel frame structures using probabilistic assessment. To this aim, first, a set were designed site class C. The examined 3-, 6-, and 9-storey frames according ASCE7-16. Then, assuming actual had been B, C, or D, vulnerability assessments performed OpenSees software. For purpose, two-dimensional model each structure was undergone incremental nonlinear dynamic analysis (IDA) subjected far-field, near-field (with pulse), (without pulse) ground motions FEMA-P695. take into account effect soil-structure interaction (SSI) on exceedance probability models, foundations simulated as flexible elements. fragility curves developed under motion record accordingly collapse margin ratio calculated. results indicated within LS performance level at Sa(Design), B decreases slightly but D tends increase significantly, especially height increases.