SOIL LIQUEFACTION UNDER SEISMIC IMPACT
Keywords:
Soil liquefaction, seismic loading, pore pressure, saturated sand, effective stress, dam stability, SPT test, cyclic resistanceAbstract
This article presents a theoretical and experimental analysis of the liquefaction of water-saturated, cohesionless soils under seismic and cyclic loading. The author explains the underlying physics of this process, which involves an increase in pore pressure and a decrease in effective stress, leading to a loss of the bearing capacity of soil massifs and dams. The paper systematizes the key factors influencing liquefaction potential: soil density, vibration level and duration, soil type, and drainage conditions. Seismic resistance assessment methods based on the standard penetration test (SPT) are discussed in detail, as well as the use of correction factors to account for burial depth, initial shear stresses, and earthquake magnitude. Graphical representations of residual soil strength and stability criteria used in modern geotechnical analysis (including the Finn-Byrne model) are presented.
References
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