File Download

There are no files associated with this item.

  Links for fulltext
     (May Require Subscription)
Supplementary

Article: On the time-dependent behaviour of glacial sediments: a geotechnical approach

TitleOn the time-dependent behaviour of glacial sediments: a geotechnical approach
Authors
KeywordsCrystallography
Glacial Geology
Glaciers
Lithology
Mineralogy
Minerals
Plastics
Sedimentology
Soil Mechanics
Soils
Stiffness
Test Facilities
Testing
Issue Date2009
PublisherPergamon. The Journal's web site is located at http://www.elsevier.com/locate/quascirev
Citation
Quaternary Science Reviews, 2009, v. 28 n. 7-8, p. 693-707 How to Cite?
AbstractSoft sediments can deform under both changes in stress and changes in strain rate, as well as during sustained loading (e.g. creep). In glacial conditions, soft subglacial sediments can contribute to glacier movements, and when the ice/sediment system is coupled, the rate-sensitivity of the sub-layer can affect the velocity of the glacier. These issues have been the object of studies by several geologists. In parallel, the effects of time and strain rate on the behaviour of soils have been studied for many years by geotechnical engineers, to estimate the long-term performance of ground structures. This paper applies the knowledge acquired in soil mechanics to a geological problem: results on two glacial sediments of different origins, obtained from advanced geotechnical laboratory tests, are presented and analysed in the light of recent advances in soil mechanics. Independently of time effects, the test data show that the pre-failure behaviour is not elastic but that the sediments develop plastic strains before reaching their peak strength, with the stiffness gradually degrading. Results from tests performed with variable strain rates suggest that the time-dependent (viscous) behaviour of the sediments may be governed by their mineralogy, in particular the presence of plastic fines. The viscous behaviour observed in the plastic tills seems to affect the pre-failure behaviour only, for example the yield surface, stiffness, strength, but the criteria of failure, e.g. critical or residual angle of failure are found to be constant and independent of strain rate. The test data also suggest that the viscous behaviour may be related to stress level, being more prevalent at low stresses. These results, obtained under laboratory-controlled conditions, over a large range of strains, pre- and post-peak strength, are a necessary step towards developing constitutive models for subglacial sediments rigorously. It is only after this has been achieved that such models should be implemented in finite element code to analyse ice/sediment systems, with the aim to understand glacier movements better. © 2008 Elsevier Ltd. All rights reserved.
Persistent Identifierhttp://hdl.handle.net/10722/91200
ISSN
2015 Impact Factor: 4.521
2015 SCImago Journal Rankings: 2.928
ISI Accession Number ID
References

 

DC FieldValueLanguage
dc.contributor.authorAltuhafi, FNen_HK
dc.contributor.authorBaudet, BAen_HK
dc.contributor.authorSammonds, Pen_HK
dc.date.accessioned2010-09-17T10:14:47Z-
dc.date.available2010-09-17T10:14:47Z-
dc.date.issued2009en_HK
dc.identifier.citationQuaternary Science Reviews, 2009, v. 28 n. 7-8, p. 693-707en_HK
dc.identifier.issn0277-3791en_HK
dc.identifier.urihttp://hdl.handle.net/10722/91200-
dc.description.abstractSoft sediments can deform under both changes in stress and changes in strain rate, as well as during sustained loading (e.g. creep). In glacial conditions, soft subglacial sediments can contribute to glacier movements, and when the ice/sediment system is coupled, the rate-sensitivity of the sub-layer can affect the velocity of the glacier. These issues have been the object of studies by several geologists. In parallel, the effects of time and strain rate on the behaviour of soils have been studied for many years by geotechnical engineers, to estimate the long-term performance of ground structures. This paper applies the knowledge acquired in soil mechanics to a geological problem: results on two glacial sediments of different origins, obtained from advanced geotechnical laboratory tests, are presented and analysed in the light of recent advances in soil mechanics. Independently of time effects, the test data show that the pre-failure behaviour is not elastic but that the sediments develop plastic strains before reaching their peak strength, with the stiffness gradually degrading. Results from tests performed with variable strain rates suggest that the time-dependent (viscous) behaviour of the sediments may be governed by their mineralogy, in particular the presence of plastic fines. The viscous behaviour observed in the plastic tills seems to affect the pre-failure behaviour only, for example the yield surface, stiffness, strength, but the criteria of failure, e.g. critical or residual angle of failure are found to be constant and independent of strain rate. The test data also suggest that the viscous behaviour may be related to stress level, being more prevalent at low stresses. These results, obtained under laboratory-controlled conditions, over a large range of strains, pre- and post-peak strength, are a necessary step towards developing constitutive models for subglacial sediments rigorously. It is only after this has been achieved that such models should be implemented in finite element code to analyse ice/sediment systems, with the aim to understand glacier movements better. © 2008 Elsevier Ltd. All rights reserved.en_HK
dc.languageengen_HK
dc.publisherPergamon. The Journal's web site is located at http://www.elsevier.com/locate/quascireven_HK
dc.relation.ispartofQuaternary Science Reviewsen_HK
dc.subjectCrystallographyen_HK
dc.subjectGlacial Geologyen_HK
dc.subjectGlaciersen_HK
dc.subjectLithologyen_HK
dc.subjectMineralogyen_HK
dc.subjectMineralsen_HK
dc.subjectPlasticsen_HK
dc.subjectSedimentologyen_HK
dc.subjectSoil Mechanicsen_HK
dc.subjectSoilsen_HK
dc.subjectStiffnessen_HK
dc.subjectTest Facilitiesen_HK
dc.subjectTestingen_HK
dc.titleOn the time-dependent behaviour of glacial sediments: a geotechnical approachen_HK
dc.typeArticleen_HK
dc.identifier.emailBaudet, BA:baudet@hku.hken_HK
dc.identifier.authorityBaudet, BA=rp01303en_HK
dc.description.naturelink_to_subscribed_fulltext-
dc.identifier.doi10.1016/j.quascirev.2008.07.016en_HK
dc.identifier.scopuseid_2-s2.0-61649100055en_HK
dc.relation.referenceshttp://www.scopus.com/mlt/select.url?eid=2-s2.0-61649100055&selection=ref&src=s&origin=recordpageen_HK
dc.identifier.volume28en_HK
dc.identifier.issue7-8en_HK
dc.identifier.spage693en_HK
dc.identifier.epage707en_HK
dc.identifier.isiWOS:000265005700010-
dc.publisher.placeUnited Kingdomen_HK
dc.identifier.scopusauthoridAltuhafi, FN=25637246000en_HK
dc.identifier.scopusauthoridBaudet, BA=15841467600en_HK
dc.identifier.scopusauthoridSammonds, P=6603943658en_HK

Export via OAI-PMH Interface in XML Formats


OR


Export to Other Non-XML Formats