Experimental observations and modelling of compaction bands in oedometric tests on high porosity rocks

Castellanza, R; Gerolymatou, E; Nova, R

dc.contributor.author	Castellanza, R	en
dc.contributor.author	Gerolymatou, E	en
dc.contributor.author	Nova, R	en
dc.date.accessioned	2014-03-01T01:30:27Z
dc.date.available	2014-03-01T01:30:27Z
dc.date.issued	2009	en
dc.identifier.issn	0039-2103	en
dc.identifier.uri	https://dspace.lib.ntua.gr/xmlui/handle/123456789/19594
dc.subject	Compaction bands	en
dc.subject	Constitutive laws	en
dc.subject	Oedometer	en
dc.subject	Plasticity	en
dc.subject	Soft rocks	en
dc.subject.classification	Materials Science, Characterization & Testing	en
dc.subject.other	Axial stress	en
dc.subject.other	Calcarenite	en
dc.subject.other	Cohesionless materials	en
dc.subject.other	Compaction bands	en
dc.subject.other	Constitutive laws	en
dc.subject.other	Elastoplastic strain	en
dc.subject.other	Experimental observation	en
dc.subject.other	High-porosity rocks	en
dc.subject.other	Mechanical response	en
dc.subject.other	Oedometer	en
dc.subject.other	Oedometers	en
dc.subject.other	Oedometric test	en
dc.subject.other	Radial stress	en
dc.subject.other	Second phase	en
dc.subject.other	Soft rocks	en
dc.subject.other	Stress decrease	en
dc.subject.other	Stress paths	en
dc.subject.other	Three phasis	en
dc.subject.other	Void ratios	en
dc.subject.other	Compaction	en
dc.subject.other	Plasticity	en
dc.subject.other	Rocks	en
dc.subject.other	Stress-strain curves	en
dc.subject.other	Stresses	en
dc.title	Experimental observations and modelling of compaction bands in oedometric tests on high porosity rocks	en
heal.type	journalArticle	en
heal.identifier.primary	10.1111/j.1475-1305.2008.00578.x	en
heal.identifier.secondary	http://dx.doi.org/10.1111/j.1475-1305.2008.00578.x	en
heal.language	English	en
heal.publicationDate	2009	en
heal.abstract	Experimental results obtained in a series of displacement controlled oedometric tests on soft rocks are presented. Four different materials characterised by a high void ratio have been examined; three natural soft rocks and an artificial one. The materials under investigation were conchyliates stone, calcarenite, pumice stone and Gasbeton. In order to monitor the stress path as well, a soft oedometer ring was designed and constructed for the measurement of the radial stresses. The observed behaviour can be divided in three phases. After an initial phase in which the mechanical response is essentially elastic, a second phase starts, in which bonds are progressively broken, so that in the axial stress-strain curve a stress decrease is recorded and in some cases, a sort of 'curl'appears in the stress path. This is associated to the occurrence of strain non-homogeneities in the form of compaction bands. In the final part of the experiment the axial stress increases exponentially and the stress path returns to be linear, as the one expected for a cohesionless material. The experimental behaviour is reproduced by means of an elastoplastic strain-hardening/softening constitutive model and the occurrence of compaction bands is theoretically predicted. © 2009 Blackwell Publishing Ltd.	en
heal.publisher	WILEY-BLACKWELL PUBLISHING, INC	en
heal.journalName	Strain	en
dc.identifier.doi	10.1111/j.1475-1305.2008.00578.x	en
dc.identifier.isi	ISI:000269708100004	en
dc.identifier.volume	45	en
dc.identifier.issue	5	en
dc.identifier.spage	410	en
dc.identifier.epage	423	en