Shear Strength of Transparent Gelita—The Effect of the Mixture Ratio, Displacement Rate, and Over-Consolidation Ratio

Transparent soils combined with non-invasive imaging techniques allow internal visualization of geotechnical processes. Oil-based transparent silica has been traditionally used for measurements of deformation patterns, soil structure interaction (SSI), flow pattern, and permeability. New water based environmentally friendly transparent material, Gelita, can be used as a transparent soil to model fine grain clay soils. Gelita has been extensively used in applied mechanics as a standard target to test bullets or to simulate human tissue. However, the potential of this material to serve as a soil surrogate and its correlation to basic geotechnical properties have not yet been investigated. Material properties and transparency of Gelita depend on its mixture ratio with water. For example, a 5% by mass Gelita mixture offers high optical transparency; however, it exhibits extremely low strength characteristics. As the mixture ratio (density) of Gelita increases, its transparency is reduced, but it offers a higher strength. This paper investigates the effect of Gelita mixture ratio, confinement, displacement rate and over-consolidation ratio on the resulting shear strength, for the purpose of being used as a soil surrogate for modeling applications.