ATTENUATION ANALYSIS ON SOIL STRUCTURE BASED ON WAVELET SPECTROGRAM (116G)

ABSTRACT Many problems related to geotechnical structures, the wave attenuation is useful for determining theeffects of vibration on the affected area. Many studies have been also conducted to obtain thedamping and empirical correlations between the damping ratio in term attenuation and the amountof radiated energy compared to the frequency of vibration and type of soil. The aim of this paper isto determine the frequency-independent attenuation coefficient generated Rayleigh wave on soilmedium using a wavelet spectrogram analysis. This method improves a common used signalprocessing tools, e.g., Fourier analysis, for attenuation analyses which fail to identify when certaincharacteristic features occur in a waveform. The time-frequency character of wavelet transformsallows increased flexibility as both traditional time and frequency domain system identificationapproaches can be exploited to examine nonlinear and nonstationary seismic events that are inessence obscured by traditional spectral approaches. A frequency-independent attenuation empiricalcoefficient was obtained from wavelet spectrogram analysis. This study is conducted to show thecapability of wavelet spectrogram analysis for attenuation measurement of soil layer profile.Keywords: attenuation, soil structure, wavelet