Full-scale dynamic response of an RC building under weak seismic motions using earthquake recordings, ambient vibrations and modelling
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TLDR
In this paper, an enhanced modal analysis technique (Frequency Domain Decomposition) was used to process ambient vibration recordings taken at the Grenoble City Hall building (France), which can contribute to the understanding of the seismic building response and the good relevancy of a modal model based on ambient vibrations for estimating the structural deformation under moderate earthquakes.Abstract:
In countries with a moderate seismic hazard, the classical methods developed for strong motion prone countries to estimate the seismic behaviour and subsequent vulnerability of existing buildings are often inadequate and not financially realistic. The main goals of this paper are to show how the modal analysis can contribute to the understanding of the seismic building response and the good relevancy of a modal model based on ambient vibrations for estimating the structural deformation under moderate earthquakes. We describe the application of an enhanced modal analysis technique (Frequency Domain Decomposition) to process ambient vibration recordings taken at the Grenoble City Hall building (France). The frequencies of ambient vibrations are compared with those of weak earthquakes recorded by the French permanent accelerometric network (RAP) that was installed to monitor the building. The frequency variations of the building under moderate earthquakes are shown to be slight (~2%) and therefore ambient vibration frequencies are relevant over the elastic domain of the building. The modal parameters extracted from ambient vibrations are then used to determine the 1D lumped-mass model in order to reproduce the inter-storey drift under weak earthquakes and to fix a 3D numerical model that could be used for strong earthquakes. The correlation coefficients between data and synthetic motion are close to 80% and 90% in horizontal directions, for the 1D and 3D modelling, respectively.read more
Citations
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References
More filters
Journal ArticleDOI
The use of fast Fourier transform for the estimation of power spectra: A method based on time averaging over short, modified periodograms
TL;DR: In this article, the use of the fast Fourier transform in power spectrum analysis is described, and the method involves sectioning the record and averaging modified periodograms of the sections.
Journal ArticleDOI
Modal identification of output-only systems using frequency domain decomposition
TL;DR: By introducing a decomposition of the spectral density function matrix, the response spectra can be separated into a set of single degree of freedom systems, each corresponding to an individual mode, and close modes can be identified with high accuracy even in the case of strong noise contamination of the signals.
Modal Identification of Output-Only Systems using Frequency Domain Decomposition
TL;DR: In this paper, a decomposition of the spectral density function matrix is introduced for the modal identification of output-only systems, i.e. in the case where the modality parameters must be estimated without knowing the input of the system.
Journal ArticleDOI
A study on the duration of strong earthquake ground motion
Mi D. Trifunac,A. G. Brady +1 more
TL;DR: A simple definition of the duration of strong earthquake ground motion based on the mean-square integral of motion has been presented in this article, which is closely related to that part of the strong motion which contributes significantly to the seismic energy as recorded at a point and to the related spectral amplitudes.