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DOE OSTI · 3008863

Influence of gradation on failure mode of saturated sand at particle scale

Elnur, Mohammed [University of Tennessee]·Alshibli, Khalid [University of Tennessee]
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Abstract

Extensive research has been reported in the literature to characterize the failure mode of dry sand using various experimental techniques such as surface optical imaging, photo-elastic materials, three-dimensional (3D) computed tomography (CT), and 3D synchrotron micro-computed tomography (SMT). However, there is a limited literature about the behavior of saturated sand. This paper presents the results of axisymmetric triaxial compression (ATC) experiments that were conducted on saturated sand specimens. The behavior of specimens composed of a uniform sand with grain size between US sieves #40 and #50 is compared to specimens conducted on the same sand that has a wider gradation. 3D SMT technique was used to acquire 3D scans while shearing the specimens to probe localized events that are completely missed or misinterpreted when analyzing ATC measurements based on global standard measurements. The results show a higher effective principal stress ratio (EPSR) for the non-uniform specimen and a thicker shear band when compared to uniform specimen.

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Elnur, Mohammed [University of Tennessee], Alshibli, Khalid [University of Tennessee]. 2025-09-15. Influence of gradation on failure mode of saturated sand at particle scale. https://doi.org/10.1201/9781003645931

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