FEATURES OF DYNAMIC INSTABILITY OF SOILS AND ROCKS AND THEIR CONSIDERATION WHEN SELECTING A DESIGN ACCELEROGRAM
Keywords:
dynamic instability, liquefaction, quasi-thixotropy, fatigue, accelerogramAbstract
This article examines the mechanisms of dynamic instability in various soil types: liquefaction of water-saturated sands, quasi-thixotropy of clay systems, and fatigue failure of rock. The author demonstrates that the choice of a design accelerogram should depend on the site's geological cross-section: for sands, the recording duration is critical, for clays, the frequency content, and for rock masses, peak accelerations. The proposed classification allows engineers to model worst-case seismic scenarios, taking into account the structural features and heterogeneity of the soils.
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