Advanced

Observing strain localisation processes in bio-cemented sand using x-ray imaging

Tagliaferri, Francesco; Waller, Jack; Ando, Edward; Hall, Stephen LU ; Viggiani, Gioacchino; Besuelle, Pierre and DeJong, Jason T. (2011) In Granular Matter 13. p.247-250
Abstract
In-situ x-ray tomography has been used to follow deformation processes in 3D during two triaxial compression tests, one on a specimen of bio-cemented Ottawa 50-70 sand and the other on a specimen of the non-cemented sand. The global stress-strain responses show that the bio-cementation process increases the shear strength (peak deviator stress is approximately doubled), and causes the material to exhibit a linear behaviour up until peak, as well as increasing the dilatancy angle. The residual strength of the two samples is very close at large strain. Quantitative 3D digital image analysis (porosity, cement-density and strain field measurements), reveals that a dilatant shear band gradually develops pre-peak in the reference material. The... (More)
In-situ x-ray tomography has been used to follow deformation processes in 3D during two triaxial compression tests, one on a specimen of bio-cemented Ottawa 50-70 sand and the other on a specimen of the non-cemented sand. The global stress-strain responses show that the bio-cementation process increases the shear strength (peak deviator stress is approximately doubled), and causes the material to exhibit a linear behaviour up until peak, as well as increasing the dilatancy angle. The residual strength of the two samples is very close at large strain. Quantitative 3D digital image analysis (porosity, cement-density and strain field measurements), reveals that a dilatant shear band gradually develops pre-peak in the reference material. The cemented sample however undergoes an abrupt change of deformation mechanism at peak stress: from homogeneous deformation to localised dilatant shearing, which is associated with a local loss of cementation. (Less)
Please use this url to cite or link to this publication:
author
publishing date
type
Contribution to journal
publication status
published
subject
in
Granular Matter
volume
13
pages
247 - 250
publisher
Springer New York
external identifiers
  • scopus:79958178352
ISSN
1434-7636
DOI
10.1007/s10035-011-0257-4
language
English
LU publication?
no
id
18a66339-32d3-4fcb-9a92-b48e7c103ce5 (old id 2441183)
date added to LUP
2012-04-27 14:19:21
date last changed
2017-10-01 04:56:53
@article{18a66339-32d3-4fcb-9a92-b48e7c103ce5,
  abstract     = {In-situ x-ray tomography has been used to follow deformation processes in 3D during two triaxial compression tests, one on a specimen of bio-cemented Ottawa 50-70 sand and the other on a specimen of the non-cemented sand. The global stress-strain responses show that the bio-cementation process increases the shear strength (peak deviator stress is approximately doubled), and causes the material to exhibit a linear behaviour up until peak, as well as increasing the dilatancy angle. The residual strength of the two samples is very close at large strain. Quantitative 3D digital image analysis (porosity, cement-density and strain field measurements), reveals that a dilatant shear band gradually develops pre-peak in the reference material. The cemented sample however undergoes an abrupt change of deformation mechanism at peak stress: from homogeneous deformation to localised dilatant shearing, which is associated with a local loss of cementation.},
  author       = {Tagliaferri, Francesco and Waller, Jack and Ando, Edward and Hall, Stephen and Viggiani, Gioacchino and Besuelle, Pierre and DeJong, Jason T.},
  issn         = {1434-7636},
  language     = {eng},
  pages        = {247--250},
  publisher    = {Springer New York},
  series       = {Granular Matter},
  title        = {Observing strain localisation processes in bio-cemented sand using x-ray imaging},
  url          = {http://dx.doi.org/10.1007/s10035-011-0257-4},
  volume       = {13},
  year         = {2011},
}