Sensitivity Analysis of the Seismic Response of Steel Moment Frames under Different Earthquake Scenarios

This research examines the influence of the two main types of earthquake mechanisms (i.e., subduction and crustal) on the seismic response of steel moment frames (SMFs). Nonlinear time history analyses are conducted on five archetype SMFs using two suites of selected unscaled recorded ground motions. The first suite consists of records from subduction earthquakes, while the second suite consists of unscaled crustal ground motions that are spectrally equivalent to the subduction ground motion suite. The differences between the two seismic environments are analyzed by conducting a sensitivity analysis of the seismic response of the SMFs against ground motion intensity measures. The results indicate that peak floor accelerations and inter-story drift ratios under subduction earthquakes are statistically higher than their counterparts from crustal earthquakes. On average, peak floor accelerations and inter-story drifts of the SMFs are amplified by 1.43 and 1.13, respectively, when subjected to ground motions from subduction sources.