Seismic isolation of buildings for vertical earthquake excitations
type: CreativeWork
description: This thesis concerns a seismic isolation mechanism for vertical component of earthquake. The vertical component of earthquake can be stronger and more destructive than the horizontal component in near-fault areas, for instance, Christchurch earthquake in New Zealand in 2011 or Bam earthquake in Iran in 2003. Therefore, this needs to be considered in designing and retrofitting structures to reduce damage to buildings and human lives. This thesis develops a numerical and experimental model of the seismic isolation based on quasi-zero-stiffness-system (QZSS) and high-static-low-dynamic-stiffness-system (HSLDSS) concepts. The results suggest the HSLDSS considered could be a practical solution for decreasing the response of the system to the vertical component of earthquake. Analytical and numerical models of a HSLDSS and a QZSS are developed. The behaviour of the mechanism subjected to static loading as well as time harmonic excitation is investigated. The harmonic balance method and the direct numerical integration method are employed to solve the equations of motion for the system. In addition, the effect of each design parameter is studied when the structure is subjected to static and harmonic excitation loadings. The impact of uncertainties in the payload as well as mistuning in the system are addressed. It is seen that the QZSS is very sensitive to any changes in payload or mistuning, while HSLDSS is unaffected by slight changes to load or initial geometry. In addition, the effects of linear and nonlinear friction elements in the model are investigated. It is seen that friction decreases the performance of the system and needs to be minimised. The response of the HSLDSS mechanism subjected to 23 near-fault earthquake ground motions is presented and discussed. Moreover, the mechanism design variables (initial geometry, static loading, stiffness of the springs) which minimise the peak acceleration, RMS response, and peak displacement are investigated. The behaviour o…
abstract: This thesis concerns a seismic isolation mechanism for vertical component of earthquake. The vertical component of earthquake can be stronger and more destructive than the horizontal component in near-fault areas, for instance, Christchurch earthquake in New Zealand in 2011 or Bam earthquake in Iran in 2003. Therefore, this needs to be considered in designing and retrofitting structures to reduce damage to buildings and human lives. This thesis develops a numerical and experimental model of the seismic isolation based on quasi-zero-stiffness-system (QZSS) and high-static-low-dynamic-stiffness-system (HSLDSS) concepts. The results suggest the HSLDSS considered could be a practical solution for decreasing the response of the system to the vertical component of earthquake. Analytical and numerical models of a HSLDSS and a QZSS are developed. The behaviour of the mechanism subjected to static loading as well as time harmonic excitation is investigated. The harmonic balance method and the direct numerical integration method are employed to solve the equations of motion for the system. In addition, the effect of each design parameter is studied when the structure is subjected to static and harmonic excitation loadings. The impact of uncertainties in the payload as well as mistuning in the system are addressed. It is seen that the QZSS is very sensitive to any changes in payload or mistuning, while HSLDSS is unaffected by slight changes to load or initial geometry. In addition, the effects of linear and nonlinear friction elements in the model are investigated. It is seen that friction decreases the performance of the system and needs to be minimised. The response of the HSLDSS mechanism subjected to 23 near-fault earthquake ground motions is presented and discussed. Moreover, the mechanism design variables (initial geometry, static loading, stiffness of the springs) which minimise the peak acceleration, RMS response, and peak displacement are investigated. The behaviour o…
author: Eskandary Malayery, Fatemeh (Elena)
keywords: Vertical earthquake excitations, Base isolation, Near-fault areas, Quasi zero stiffness system, High-static-low-dynamic-stiffness system
license: https://researchcommons.waikato.ac.nz/bitstreams/f014b4bb-6b03-452b-ab73-7f5f084fc874/download
date published: 2022
date modified: 2026-07-24T05:57:36Z
provider: University Waikato
publisher: Networked Digital Library of Theses and Dissertations
type: WebPage
source organization: The University of Waikato