Altmetric
Numerical assessment of the effects of end-restraints and a pre-existing fissure on the interpretation of triaxial tests on stiff clays
File | Description | Size | Format | |
---|---|---|---|---|
![]() | Accepted version | 2.29 MB | Adobe PDF | View/Open |
Title: | Numerical assessment of the effects of end-restraints and a pre-existing fissure on the interpretation of triaxial tests on stiff clays |
Authors: | Cui, W Potts, DM Pedro, AMG Zdravkovic, L |
Item Type: | Journal Article |
Abstract: | Conventional laboratory triaxial tests apply axisymmetric boundary conditions to a cylindrical sample which has an axisymmetric geometry. For a homogeneous sample this implies that the deformed shape of the sample should maintain an axisymmetric geometry during the test. Consequently, the sample should deform in a barrelling mode and if slip planes develop they should define a cup and cone-like failure surface. However, in many triaxial tests such behaviour is not observed, especially as failure is approached when a planar slip surface develops. Such a deformation mode is not axisymmetric. One reason for this behaviour is that a fissure pre-exists in the sample. Employing hydro-mechanically coupled three-dimensional finite-element analyses, this paper investigates the influence of a single fissure in a triaxial sample of stiff clay on its behaviour throughout the test, focusing on the fissure position, orientation, strength and stiffness, in conjunction with the sample's end-restraints (rough or smooth). The effects are quantified in terms of the sample's overall stiffness and strength, indicating that the presence of a fissure can affect the very small strain stiffness, and that it has a significant effect on the strength of the sample, demonstrating that the conventional methods used to interpret laboratory tests may give unconservative results. The results also show a significant effect of the conditions at the top and bottom surfaces of the sample, where in particular the lateral restraint and rough ends introduce ‘bending’ in the sample. |
Issue Date: | 1-Sep-2021 |
Date of Acceptance: | 12-Jun-2020 |
URI: | http://hdl.handle.net/10044/1/79486 |
DOI: | 10.1680/jgeot.19.P.318 |
ISSN: | 0016-8505 |
Publisher: | ICE Publishing |
Start Page: | 765 |
End Page: | 780 |
Journal / Book Title: | Geotechnique: international journal of soil mechanics |
Volume: | 71 |
Issue: | 9 |
Copyright Statement: | © 2020 ICE Publishing, all rights reserved. Original article available at https://doi.org/10.1680/jgeot.19.P.318. Permission is granted by ICE Publishing to print one copy for personal use. Any other use of these PDF files is subject to reprint fees. |
Sponsor/Funder: | Geotechnical Consulting Group LLP |
Funder's Grant Number: | CISM_P60087 |
Keywords: | Geological & Geomatics Engineering 0905 Civil Engineering 0907 Environmental Engineering 0914 Resources Engineering and Extractive Metallurgy |
Publication Status: | Published |
Online Publication Date: | 2020-12-16 |
Appears in Collections: | Civil and Environmental Engineering Faculty of Engineering |