2019 CSCE Annual Conference - Laval (Greater Montreal) Conference
Dr. Rola Assi, École de Technologie Supérieure
Ms. Banafsheh Hasanpour, École de technologie supérieure
The seismic design of non-structural components (NSCs) requires the computation of accelerations at the building floor levels on which they are installed. It was shown in recent studies that these accelerations depend on the building dynamic properties that are in turn affected by the presence of NSCs. Nowadays, advanced construction techniques and architectural innovations make it increasingly possible to build more complex buildings that often have irregularities. Unlike regular buildings,very few studies focused on the seismic behavior of NSCs located in irregular buildings. In this paper, the effect of non-structural components on seismic floors acceleration amplification (FAA) was assessed in an irregular case study building named “maison des étudiants” (MDE) and located on the campus of the École de Technologie Supérieure (ETS) in Montreal. The MDE is an irregular 6-story building with steel and reinforced concrete structural system. Floor accelerations were determined by performing seismic simulations on two calibrated building models representing the building at two construction stages: bare-frame without NSCs and full frame with NSCs including masonry walls, curtain walls and secondary beams. These models were implemented in Finite Element Software (ETABS) and calibrated using ambient vibration measurements. Each model was subjected to 12 earthquakes calibrated to match Montréal’s uniform hazard spectrum.
The results show that the computed FAA corresponding to both construction stages are in most cases higher than the height coefficients prescribed by the the National Building Code of Canada (NBCC), especially at the roof level. This can be attributed in large part to the amplification of the accelerations caused by the torsion. In addition, less FAA was observed at the full stage when compared to the bare frame stage and this tendency is less pronounced as the ditance of the fault increases. It was also shown that the frequency content of the earthquakes has a great influence on the FAA. In effect, earthquakes with higher magnitude and lower frequency content lead to higher height coefficients.
Keywords: seismic floors acceleration, torsion, frequency content of earthquakes, non-structural components, height amplification factor, NBCC