Stress-dependent flow through fractured clay till

A laboratory study

John E. Sims, Derek Elsworth, John A. Cherry

Research output: Contribution to journalArticle

10 Citations (Scopus)

Abstract

Stress-dependent hydraulic conductivities of weathered fractured clay till were measured in a flexible-wall permeameter. Measured conductivities were in the range 10-7 to 10-8 cm/s, of the same order as the clay matrix (10-8 cm/s), and representing equivalent hydraulic apertures in the range 0-5 μm. In general, the isolated fractures exhibited strongly nonlinear closure characteristics and hysteretic behaviour under stress reversal. Some fracture samples exhibited only weak stress dependency, representing observable features of only nominal conductivity. Results of the investigations suggest fractures are closed to residual aperture for an overburden load of the order of 12 m, this defining an effective closure depth and the degree of maximum useful compactive effort that might be applied to "seal" fractures and reduce fluid migration.

Original languageEnglish (US)
Pages (from-to)449-457
Number of pages9
JournalCanadian Geotechnical Journal
Volume33
Issue number3
DOIs
StatePublished - Jan 1 1996

Fingerprint

Clay
clay
conductivity
permeameter
Hydraulic conductivity
overburden
Seals
hydraulic conductivity
Hydraulics
hydraulics
matrix
Fluids
fluid
laboratory

All Science Journal Classification (ASJC) codes

  • Civil and Structural Engineering

Cite this

@article{c1e8dcb1b71f4b108038f8459c816e33,
title = "Stress-dependent flow through fractured clay till: A laboratory study",
abstract = "Stress-dependent hydraulic conductivities of weathered fractured clay till were measured in a flexible-wall permeameter. Measured conductivities were in the range 10-7 to 10-8 cm/s, of the same order as the clay matrix (10-8 cm/s), and representing equivalent hydraulic apertures in the range 0-5 μm. In general, the isolated fractures exhibited strongly nonlinear closure characteristics and hysteretic behaviour under stress reversal. Some fracture samples exhibited only weak stress dependency, representing observable features of only nominal conductivity. Results of the investigations suggest fractures are closed to residual aperture for an overburden load of the order of 12 m, this defining an effective closure depth and the degree of maximum useful compactive effort that might be applied to {"}seal{"} fractures and reduce fluid migration.",
author = "Sims, {John E.} and Derek Elsworth and Cherry, {John A.}",
year = "1996",
month = "1",
day = "1",
doi = "10.1139/t96-066",
language = "English (US)",
volume = "33",
pages = "449--457",
journal = "Canadian Geotechnical Journal",
issn = "0008-3674",
publisher = "National Research Council of Canada",
number = "3",

}

Stress-dependent flow through fractured clay till : A laboratory study. / Sims, John E.; Elsworth, Derek; Cherry, John A.

In: Canadian Geotechnical Journal, Vol. 33, No. 3, 01.01.1996, p. 449-457.

Research output: Contribution to journalArticle

TY - JOUR

T1 - Stress-dependent flow through fractured clay till

T2 - A laboratory study

AU - Sims, John E.

AU - Elsworth, Derek

AU - Cherry, John A.

PY - 1996/1/1

Y1 - 1996/1/1

N2 - Stress-dependent hydraulic conductivities of weathered fractured clay till were measured in a flexible-wall permeameter. Measured conductivities were in the range 10-7 to 10-8 cm/s, of the same order as the clay matrix (10-8 cm/s), and representing equivalent hydraulic apertures in the range 0-5 μm. In general, the isolated fractures exhibited strongly nonlinear closure characteristics and hysteretic behaviour under stress reversal. Some fracture samples exhibited only weak stress dependency, representing observable features of only nominal conductivity. Results of the investigations suggest fractures are closed to residual aperture for an overburden load of the order of 12 m, this defining an effective closure depth and the degree of maximum useful compactive effort that might be applied to "seal" fractures and reduce fluid migration.

AB - Stress-dependent hydraulic conductivities of weathered fractured clay till were measured in a flexible-wall permeameter. Measured conductivities were in the range 10-7 to 10-8 cm/s, of the same order as the clay matrix (10-8 cm/s), and representing equivalent hydraulic apertures in the range 0-5 μm. In general, the isolated fractures exhibited strongly nonlinear closure characteristics and hysteretic behaviour under stress reversal. Some fracture samples exhibited only weak stress dependency, representing observable features of only nominal conductivity. Results of the investigations suggest fractures are closed to residual aperture for an overburden load of the order of 12 m, this defining an effective closure depth and the degree of maximum useful compactive effort that might be applied to "seal" fractures and reduce fluid migration.

UR - http://www.scopus.com/inward/record.url?scp=0030153184&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0030153184&partnerID=8YFLogxK

U2 - 10.1139/t96-066

DO - 10.1139/t96-066

M3 - Article

VL - 33

SP - 449

EP - 457

JO - Canadian Geotechnical Journal

JF - Canadian Geotechnical Journal

SN - 0008-3674

IS - 3

ER -