@article { author = {Roshan- Miavaghi, A. and Yazdani, A. and Salimi, M.R.}, title = {Pulse-like ground motion simulation using wavelet-based Hilbert transforms}, journal = {Sharif Journal of Civil Engineering}, volume = {37.2}, number = {4.1}, pages = {69-79}, year = {2022}, publisher = {Sharif University of Technology}, issn = {2676-4768}, eissn = {2676-4776}, doi = {10.24200/j30.2021.57546.2915}, abstract = {In areas near active faults, ground motions usually show a large pulse in velocity time history. These near-field pulse-like ground motions increase the structural failure and cause extensive damage to structures. Due to the limited number of pulse-like ground motion recorded in a range of magnitude and distance, there is a small set of possible earthquake scenarios for seismic engineering in a given area, especially in areas near the fault. A new method has been proposed in this paper for simulating near-field pulse-like ground motions using instantaneous feature modeling. The proposed method is introduced based on the time-frequency process which is necessary to consider non-stationary characteristics of ground motion. In this method of simulation, wavelet-based Hilbert transform is used to extract the non-stationary characteristics of original pulse-like ground motion. The stationary wavelet transform is first applied to decompose the original ground motion into a series of subband frequency, and then the instantaneous features are obtained by applying Hilbert transform on each subband frequency. Instantaneous frequencies are modeled by Gaussian distribution and the instantaneous amplitude fitted by Gaussian curves. Approximation coefficients obtained from the last level of wavelet transform are also simulated using the Gaussian curves. Pulse-like ground motion will be simulated using Hilbert and Wavelet inverse transforms and the new generated data for the instantaneous characteristics and approximation coefficients. In this study, four pulse-like ground motions of Imperial Valley1979 and Northridge 1994 were used to verify the effectiveness of this simulation method. Simulated ground motions were compared with the recorded pulse-like ground motions and various criteria were used to confirm the effectiveness of the proposed method. Peak ground acceleration, response spectrums, and arias curves which are important parameters of ground motion were used in this paper to validate the proposed method. Simulation results not only captured the main characteristics of the recorded pulse-like ground motion, but also preserved the effects of the pulse as well.}, keywords = {Pulse-like ground motion,wavelet transform,Hilbert Transform,Instantaneous Frequency,Instantaneous Amplitude,Gaussian distribution}, title_fa = {شبیه‌سازی زمین‌لرزه ی شبه‌پالس با استفاده از تبدیل هیلبرت بر پایه ی موجک}, abstract_fa = {درنوشتار حاضر، روشی برای شبیه‌سازی زمین‌لرزه‌ی نزدیک گسل شبه‌پالس با استفاده از مدل‌سازی مشخصات آنی پیشنهاد شده است. روش پیشنهادی بر اساس فرایند زمان - بسامد است، که برای در نظر گرفتن مشخصات نامانای زمین‌لرزه ضروری است. در مطالعه‌ی حاضر، به منظور حفظ مشخصات نامانای زمین‌لرزه از تبدیلات هیلبرت و موجک مانا استفاده شده است. از تبدیل موجک مانا به منظور تجزیه‌ی سیگنال زلزله‌ی اصلی به یک سری زیرباندهای بسامدی و از تبدیل هیلبرت جهت استخراج مشخصات آنی زمین‌لرزه‌ها استفاده شده است. به منظور تولید داده‌های تصادفی جهت شبیه‌سازی زلزله‌ها از توزیع‌ها و توابع مناسب برازش شده روی مشخصات آنی و ضرایب تقریب به دست آمده از آخرین مرحله‌ی تبدیل موجک مانا استفاده شده است. در مطالعه‌ی حاضر، از چند زمین‌لرزه‌ی پالس‌دار برای بررسی کارآمد بودن روش پیشنهادی استفاده شده است. نتایج شبیه‌سازی نشان می‌دهد روش پیشنهادی به خوبی مشخصات اصلی زلزله‌ی ثبت شده را در بر می‌گیرد و همچنین آثار پالس زمین‌لرزه را نیز به خوبی حفظ می‌کند.}, keywords_fa = {زمین‌لرزه‌ی شبه‌پالس,تبدیل موجک,تبدیل هیلبرت,مشخصات آنی,توزیع گوسین}, url = {https://sjce.journals.sharif.edu/article_22516.html}, eprint = {https://sjce.journals.sharif.edu/article_22516_cbdc1fbf8038bd5611ab62b85b6f53e9.pdf} }