Piotr A. Dudziński, Damian Stefanow,
Journal of Terramechanics, Volume 86, 2019, Pages 39-46, ISSN 0022-4898
https://doi.org/10.1016/j.jterra.2019.08.003.(http://www.sciencedirect.com/science/article/pii/S0022489819301065)
Abstract: This publication series describes the phenomenon of dynamic strengthening of soils. This part presents a literature review, based on which a new tester was designed. It allows shearing of soils in a wide range of speeds, it is not susceptible to the scale effect, wall effect and the bulldozing effect, as well as it has shear kinematics adequate to the modelled process. Comparison of the test device with direct shear tester showed a substantial decrease of cohesion and increase of internal friction angle of cohesive soils with the new tester. Four different cohesive and non-cohesive soils have been investigated in this study. Dynamic shearing tests have confirmed that cohesive soils may increase shear strength by up to almost 3 times compared to quasi-static shearing. Non-cohesive soil (quartz sand) did not exhibit distinct increase of shear strength. Validation of the new criterion proved it can be used to describe the shear strength – shear speed relationship of agricultural soils. The proposed model correlated with experimental data at R2 over 0.85 for cohesive soils and over 0.64 for sand.
Keywords: Soil shear; Dynamic shearing; Shear tester; Soil strengthening