Deconvolution of Earthquake Ground Motions for Dynamic Analysis of Masonry Gravity Dams

Abstract

The present study aims at deconvolution of earthquake ground motions pertaining to dynamic analysis of masonry gravity dams. Deconvolution is a process that can be used to remove the effects of these distortions and obtain the actual ground motion. Dynamic analysis of masonry gravity dams incorporating soil-structure interaction requires the application of earthquake motion to the base of the foundation. Soil strata up to a depth of three times the height of the dam is generally included in the dam analysis. Deconvolution procedure is performed in this study for different types of earthquake ground motions and different types of soil strata present beneath the dam. In order to perform deconvolution, frequency domain approach is considered. In this frequency domain approach, the recorded ground motion data is first transformed into the frequency domain using a Fast Fourier Transform (FFT). The response at dam-foundation interface is also transformed into the frequency domain, and the two spectra are divided point-by-point. This procedure is repeated until reasonable accuracy is achieved. The deconvolved signal is then transformed back into the time domain using the inverse Fourier transform. This study provides an overview of the deconvolution of seismic ground motion using a frequency domain approach and highlights its importance in seismic research and engineering applications. Also, the importance of performing deconvolution of ground motions is assessed with respect to different types of soil strata lying underneath the dam. © The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd. 2024.