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Simulation of endurance time excitations via wavelet transform

Mashayekhi, M ; Sharif University of Technology | 2019

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  1. Type of Document: Article
  2. DOI: 10.1007/s40996-018-0208-y
  3. Publisher: Springer International Publishing , 2019
  4. Abstract:
  5. This paper puts forth a wavelet-based methodology for generating endurance time (ET) excitations. Conventional simulating practice expresses signals by acceleration values which are then computed via unconstrained nonlinear optimization. Dynamic characteristics of signals, including frequency content, are not represented directly in this type of variable definition. In this study, a new algorithm is developed to generate ET excitations in discrete wavelet transform (DWT) space. In this algorithm, signals are represented by transform coefficients. In addition, objective functions are modified in order to obtain transform coefficients and return the objective function values. The proposed method makes the filtering of the optimization variables possible so that insignificant variables can be eliminated. New excitations are generated in filtered DWT space. Different generating scenarios are used, and the results are then compared. Results show improvement in the generated excitations. It is also observed that a filtered DWT space brings about higher match with target acceleration spectra. Further, significance of generating more matched ET excitations in dynamic response assessment is examined through analyzing a multidegree of freedom structure. © 2018, Shiraz University
  6. Keywords:
  7. Endurance time method ; Nonlinear optimization ; Time history analysis ; Wavelet transform
  8. Source: Iranian Journal of Science and Technology - Transactions of Civil Engineering ; Volume 43, Issue 3 , 2019 , Pages 429-443 ; 22286160 (ISSN)
  9. URL: https://link.springer.com/article/10.1007/s40996-018-0208-y