International Institute of Earthquake Engineering and Seismology Journal of Seismology and Earthquake Engineering 1735-1669 26 1 2024 01 01 On the Vertical seismic Response of the Floor Mounted Motorized Non-Structural Components 61 70 713823 10.48303/jsee.2024.2031211.1098 EN Mahboobeh Pirizadeh Assistant Professor, Department of Civil Engineering, Faculty of Engineering, West Tehran Branch, Islamic Azad University, Tehran, Iran 0000-0002-8217-915X Alireza Karoubi M.Sc. in Earthquake Engineering, Department of Civil Engineering, Faculty of Engineering, West Tehran Branch, Islamic Azad University, Tehran, Iran Seyed Mahdi Lashgari-gehraz M.Sc. in Earthquake Engineering, Department of Civil Engineering, Faculty of Engineering, West Tehran Branch, Islamic Azad University, Tehran, Iran Journal Article 2024 06 04 Seismic design guidelines for non-structural components typically do not account for the potential interaction between the vibrations of these elements and the deflections of the host structure, especially in the vertical direction. This paper<br />examines critical seismic scenarios, such as the simultaneous vibrations from operating motorized devices (like chillers) and earthquake-induced movements, by considering the short-period spectral characteristics of vertical ground motion<br />components in near-fault regions. To address this, the amplification factor of non-structural components installed in low-rise and mid-rise steel moment-resisting frame structures was assessed using nonlinear time history analysis. The evaluation showed that the amplification factor of vertical acceleration for non-structural components with vertical mode periods below 0.5 seconds ranged from 1 to 4, depending on the number of floors in the host structure and whether the motor was operational. The operation of the chiller's motor on the roof during an earthquake increased the vertical acceleration amplification factor by 10% to 50%. These findings suggest that the current seismic code approaches, which overlook the vertical mode frequency of structural and non-structural elements, need to be reconsidered, especially in near-fault areas. https://www.jsee.ir/article_713823_318e49655cb461750c947a247eee4ced.pdf