Compressibility and dynamic properties of diatomaceous soils of Mejillones

Abstract

This article presents a comprehensive laboratory study on primary and secondary compressibility of a diatomaceous soil from Mejillones Bay in northern Chile. SEM microscopic observations of the diatom fossils and their mineralogical composition are reported. Despite its low density and high plasticity, the material reaches a high overconsolidation pressure. Over that pressure, the soil is highly compressible, presumably due to the breakage of diatoms frustules, and presents significant creep strains. Dynamic properties and shear modulus degradation curves are also reported, where the results of Gmax are consistent with values Vs of measured in-situ.