Effect of confining pressure on plastic flow of salt at 125°C

N. Muhammad, C.J. Spiers, C.J. Peach, J.H.P. de Bresser

Research output: Chapter in Book/Report/Conference proceedingChapterAcademicpeer-review

Abstract

The microphysics of crystal plastic flow of rocksalt have been studied to ascertain which dislocation mechanism controls creep at temperatures in the range 100-200 oC. This information is essential to reliably constrain extrapolation of laboratory flow laws to in-situ stresses and strain rates. For constant strain rate experiments on NaCl, microphysical models predict that climb-controlled creep should display a positive dependence of flow stress on confining pressure, at pressures where microcrack dilatancy is suppressed. By contrast, cross-slip control should exhibit a negative dependence or virtually no dependence on confining pressure. Rigorous experimentation using confining pressures well above those encountered in salt in nature is required to test which of these models might apply. We tested polycrystalline sodium chloride samples at pressures in the range 50-600 MPa at 125 oC. The results revealed that the strength of the salt increased with pressure, pointing to climb control.
Original languageEnglish
Title of host publicationMechanical Behavior of Salt VII
EditorsP. Bérest, M. Ghoreychi, F. Hadj-Hassen, M. Tijani
PublisherCRC Press
Pages57-64
ISBN (Electronic)978-0-203-10076-9
ISBN (Print)978-041562122-9
DOIs
Publication statusPublished - Apr 2012

Publication series

NameMechanical Behaviour of Salt
VolumeVII

Fingerprint

Dive into the research topics of 'Effect of confining pressure on plastic flow of salt at 125°C'. Together they form a unique fingerprint.

Cite this