Evaluation of the Efficiency of Mother Wavelet Functions for Simulating Endurance Time Excitations

Abstract

The Endurance Time (ET) method is employed as a dynamic time history technique to analyze structures under artificially intensified acceleration time histories, known as Endurance Time Excitation Functions (ETEFs). Prior studies have shown that discrete wavelet transform (DWT) is an effective approach for generating ETEFs by representing signals as transform coefficients determined through optimization procedures. However, the impact of the chosen mother wavelet function on simulated ETEF accuracy remains unexplored. This study introduces a methodology to investigate the influence of mother wavelet functions on simulated ETEFs. Specifically, 31 mother wavelet function candidates from four families (Daubechies, Coiflet, Symlet, and Bio-Orthogonal) are examined. Results reveal that the choice of the mother wavelet function can lead to approximately 15% variation in simulated ETEFs' accuracy. The Daubechies wavelet family stands out as the preferred choice, exhibiting a diminished impact compared to alternative families. Remarkably, this wavelet family is associated with an importance factor of 5.5%, significantly lower than the 13% observed for the other families. Within the Daubechies family, db12 demonstrates optimal efficiency in generating linear response-based ETEFs. The research highlights the superiority of the Daubechies wavelet family, offering valuable insights to enhance ETEF simulation accuracy and reliability for effective ET method implementation.