About the Group
This research project involves forced vibration testing of the Four Seasons office building using the nees@UCLA equipment as well as detailed system identification and numerical modeling studies. Both earthquake-type and harmonic force histories were applied to the building at the roof level, and waveforms were recorded to enable evaluations of the complete structural system response, structural component behavior (e.g., slab-column connections and pile caps), and the response of non-structural components (e.g., piping systems) as well as the influence of these components on the system response. A dense instrumentation array including accelerometers, displacement transducers, and strain gauges was deployed. A wireless local area network was installed to acquire and record waveform data remotely from the mobile command center in real-time. The detailed data set generated from the tests provide valuable insights into the performance of this common type of structural system and the reasons for the poor performance of the subject building during the Northridge earthquake.