Conclusions
In this study, the efficiency and sufficiency of 27 scalar IMs, including 13 non-structure-specific and 14 structure-specific IMs, to predict the collapse capacity of steel SMRFs with and without FVDs were investigated. For this purpose, 12 SMRF structures including three code-designed benchmark structures and nine structures derived from the benchmark structures, by changing their height or seismic mass, were considered. In addition to the 12 SMRF structures, assuming three levels of supplemental viscous damping ratio, linear and nonlinear FVDs were added to the SMRFs and 144 SMRFs with FVDs were considered. The obtained results indicated that none of the non-structurespecific IMs could satisfy both the efficiency and sufficiency criteria. The structure-specific IMs consist of Sa(T1), the spectral shape based IMs and the combined spectral shape and duration based IMs. It was indicated that among the spectral shape based IMs, IMC, INp, IMM and Saavg are more efficient than the others, but they are facing the sufficiency problems with respect to either M or SF (or both). The combined spectral shape and duration based IMs are IMC–D, IMM–D, INp–D, INp M–D, Saavg–D and Saavg M–D. Sensitivity analyses were performed to select the optimal values of the parameters for these IMs by considering the efficiency and sufficiency criteria simultaneously. After selecting the optimal values of the parameters for use in the combined spectral shape and duration based IMs, the results obtained by using these IMs were compared, and the IMs IMM–D, INp M–D and Saavg M–D were proposed as advanced scalar IMs to reliably predict the collapse capacity of steel SMRFs with FVDs.
