SEISMIC ACCELERATION RESPONSE OF TALL STRUCTURAL SYSTEMS USING NONLINEAR TIME HISTORY ANALYSIS

This study evaluates the seismic acceleration response of seven tall structural systems-Moment Resisting Frame (MRF), Shear Wall-MRF (SW-MRF), Diagrid (DG), Outrigger (OT), Belt Truss (BTS), Bundled Tube (BT), and Tube-in-Tube (TT)-subjected to six historic earthquake ground motions using nonlinear time history analysis.The focus is on top floor acceleration amplification and input-output acceleration behavior to assess acceleration-sensitive seismic performance.Results indicate that Kobe (1995) earthquake consistently produced the highest top floor accelerations, with TT, DG and SW-MRF systems exhibiting the maximum amplification due to increased global stiffness.In contrast, flexible systems like MRF and BTS showed lower acceleration magnitudes.Input-output acceleration analysis confirms significant dynamic amplification across all models, with output accelerations exceeding input ground motion by 1.6 to 4.0 times depending on system type and earthquake characteristics.Bhuj (2001) generated the minimum acceleration response.The study demonstrates that stiffer structural systems attract higher acceleration demands but provide better drift control, emphasizing the critical trade-off between stiffness enhancement and acceleration-driven nonstructural damage risk in performance-based seismic design.