Residual shear strength of fine-grained soils and soil–solid interfaces at low effective normal stresses

Abstract

A laboratory research program was undertaken to study the large-strain shear strength characteristics of fine-grained soils under low effective normal stresses (ϳ3-7 kPa). Soils that cover a wide range of plasticity and composition were utilized in the program. The interface shear strength of these soils against a number of solid surfaces having different roughness was also investigated at similar low effective normal stress levels. The findings contribute to advancing the knowledge of the parameters needed for the design of pipelines placed on sea beds and the stability analysis of shallow soil slopes. A Bromhead-type torsional ring-shear apparatus was modified to suit measuring soil-soil and soil-solid interface residual shear strengths at the low effective normal stresses. In consideration of increasing the accuracy of assessment and depicting the full-scale field behavior, the interface residual shear strengths were also measured using a macroscale interface direct shear device with a plan interface shear area of ϳ3.0 m 2 . Correlations are developed to estimate the soil-soil and soil-solid interface residual shear strengths at low effective normal stresses. The correlations are compared with soil-soil and soil-solid interface drained residual shear strengths and correlations presented in the literature.

Interface shear box tests for assessing axial pipe–soil resistance

“…For the study of interface resistance at very low normal stress, the conventional ring shear device is not well suited due to frictional forces developing between the sides of the sample and the apparatus. To address the issues related to unwanted friction, a number of new or modified direct shear and ring shear devices have been proposed (e.g., White et al 2012, Ganesan et al, 2014Wijewickreme et al, 2014;Eid et al, 2014). The simple arrangement of the tilt table means apparatus friction is absent (Najjar et al 2007).…”

Shear‐Rate‐Dependent Behavior of Clayey Bimaterial Interfaces at Landslide Stress Levels

“…Studies on the shear behavior of bimaterial interfaces between soil and concrete, steel, geotextiles, and other manufactured materials, especially under low normal stresses ( σ n = 1–100 kPa), are abundant in the literature (e.g., Boukpeti & White, ; Eid et al, ; Ganesan et al, ; Ho et al, ; Lemos & Vaughan, ; Potyondy, ; Tsubakihara & Kishida, ; Wijewickreme et al, ; Zhang & Zhang, ). Equally, in fault mechanics, many researchers have been focusing on the slip‐ and rate‐dependent behavior of rock interfaces and thin gouge layers under high normal stresses ( σ n = 1–20 MPa) to understand the behavior of faults under subseismic and coseismic slip rates (e.g., Di Toro et al, , , ; Hirose & Shimamoto, ; Perfettini & Ampuero, ; Kitajima et al, ; Togo et al, ; Yao et al, , Ma et al, ; Yao et al, ).…”

Effects of different calcium sources on the mineralization and sand curing of CaCO3by carbonic anhydrase-producing bacteria

“…The amount of deposition generated by the cured process was obtained by the method of subtraction. 21 3 Results and discussion…”