Journal of Seismology and Earthquake Engineering

Journal of Seismology and Earthquake Engineering

On the Vertical seismic Response of the Floor Mounted Motorized Non-Structural Components

Document Type : Research Article

Authors
Mahboobeh Pirizadeh 1
Alireza Karoubi 2
Seyed Mahdi Lashgari-gehraz 2
1 Assistant Professor, Department of Civil Engineering, Faculty of Engineering, West Tehran Branch, Islamic Azad University, Tehran, Iran
2 M.Sc. in Earthquake Engineering, Department of Civil Engineering, Faculty of Engineering, West Tehran Branch, Islamic Azad University, Tehran, Iran
10.48303/jsee.2024.2031211.1098
Abstract
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
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
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.
Keywords
Seismic vertical component
Non-Structural elements
Operating motorized devices
Near-field earthquakes

Subjects

Aghaei-Araei, A., Ghodrati-Ghazaani, A., Attarchian, N., Salamat, A. S. & Hasani, H., (2019). Design Spectra for Near Fault Ground Motions Considering Frequency-Dependence of Material Behavior, Research Report, Building and Housing Research Center (BHRC), Iran (in Persian).
ASCE Standard (2022). Minimum Design Loads and Associated Criteria for Buildings and Other Structures, ASCE/SEI 7-22, American Society of Civil Engineers.
Astroza, R., Pantoli, E., Selva, F., Restrepo, J. I., Hutchinson, T. C., & Conte, J. P. (2015). Experimental evaluation of the seismic response of a rooftop-mounted cooling tower. Earthquake Spectra, 31(3), 1567-1589.
Challagulla, S. P., Kontoni, D. P. N., Suluguru, A. K., Hossain, I., Ramakrishna, U., & Jameel, M. (2023). Assessing the seismic demands on non-structural components attached to reinforced concrete frames. Applied Sciences, 13(3), 1817.
Filiatrault, A., Perrone, D., Merino, R. J., & Calvi, G. M. (2021). Performance-based seismic design of nonstructural building elements. Journal of Earthquake Engineering, 25(2), 237-269.
Iranian Seismic Code. (2015). Iranian Code of Practice for Seismic Resistant Design of Buildings, Standard No. 2800, Ed. 4, Building and Housing Research Center (BHRC), Iran (in Persian).
Karoubi, A., Lashgari-gehraz, S. M., & Pirizadeh, M. (2024). Evaluation of seismic vertical component effects on non-structural elements with electric motors installed in buildings at near-fault regions.  9th International Conference on Seismology and Earthquake Engineering, Tehran, Iran.
Kazantzi, A. K., Vamvatsikos, D., & Miranda, E. (2020). Evaluation of seismic acceleration demands on building nonstructural elements. Journal of Structural Engineering, 146(7), 04020118.
Lashgari-gehraz, S. M. (2022). Evaluation of Vertical Ground Motion Effects on the Peak Acceleration Amplification Factor of Floor Mounted Non-Structural Elements in Steel Moment Frame Structures, MSc. Thesis, Faculty of Engineering, West Tehran Branch, Islamic Azad University, Tehran, Iran (in Persian).
Marin-Artieda, C., Kea, K., & Valencia, T. (2014). Studies of a rooftop cooling tower and its seismic protective system. Structures Congress, 1892-1903.
O'Reilly, G. J., Hasegawa, K., Shahnazaryan, D., Poveda, J., Fukutomi, Y., Kusaka, A., & Nakashima, M. (2023). On the fragility of non-structural elements in loss and recovery: Field observations from Japan. Earthquake Engineering & Structural Dynamics, Online Version.
Shihab, I. M., Abd Soud, W., & Jebur, N. A. (2017). Theoretical and experimental study of the vibration of a drum type washing machine at different speeds. Al-Nahrain Journal for Engineering Sciences, 20(5), 1160-1171.
UBC. (1964). Uniform Building Code, 6th ed., International Conference of Building Officials, Whittier Narrow, California.
Journal of Seismology and Earthquake Engineering
Volume 26, Issue 1
2024
Pages 61-70

  • Receive Date 04 June 2024
  • Revise Date 16 June 2024
  • Accept Date 16 June 2024
  • Publish Date 01 January 2024