Journal of the Korean GEO-environmental Society (한국지반환경공학회 논문집)

Korean Geo-Environmental Society (한국지반환경공학회)
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Analysis of Wave Propagation Characteristics in Unsaturated Clay with Emphasis on Elastic Modulus Variation

  • Weiwei Zhang (Department of Civil Engineering, INHA University) ;
  • Kiil Song (Department of Civil Engineering, INHA University)
  • Received : 2024.10.07
  • Accepted : 2024.10.22
  • Published : 2024.11.01
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Abstract

The propagation of elastic waves in soil is crucial in geotechnical and seismic engineering. Although soil is often assumed homogeneous, natural geomaterials like soil and rock possess inherent heterogeneity. This study uses FLAC 2D finite difference software to simulate wave propagation under different spatial variability parameters. Random field models and Monte Carlo methods were employed to generate random field data for soil parameters, reflecting the actual variability of soil. The study analyzes the effects of different correlation lengths, variability parameters, and saturation on the propagation characteristics of elastic waves, including wave velocity, amplitude attenuation, and waveform changes. Results show that wave propagation is most sensitive to elastic modulus variability, followed by porosity, while Poisson's ratio has minimal impact. Due to the variability of the elastic modulus, wave propagation time increases with increasing variability coefficient and correlation length. The peak amplitude decreases significantly, and the attenuation mean decreases while the variability of attenuation increases with increasing variability coefficient. Additionally, increasing soil saturation in heterogeneous soils leads to a decrease in wave velocity and an increase in attenuation. These findings contribute to a better understanding of elastic wave propagation in heterogeneous soils and improving design reliability.

Keywords

Acknowledgement

This work is supported by the Korea Agency for Infrastructure Technology Advancement (KAIA) grant funded by the Ministry of Land, Infrastructure and Transport (Grant RS-2023-00245334).

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