Analysing the effects of waste rock inclusions on tailings consolidation: Laboratory tests and modeling of the large scale in situ behavior
Frédérick L. Bolduc, Michel Aubertin
In the proceedings of: GeoMontréal 2013: 66th Canadian Geotechnical Conference; 11th joint with IAH-CNCSession: Mining Geotechnics I
ABSTRACT: Theconstructionofwasterockinclusions(WRI)intailingsimpoundmentconsistsinstrategicallyplacingtheWRIinsidetheimpoundmentduringitsoperationtoforminternalcells.Inthispaper,theauthorsinvestigatetheeffectsofdrainagefrominclusionsontailingsconsolidationduringfillingoftheimpoundmentusinglaboratorytestingdataandnumericalsimulations.Themaintestsconductedontailingsandwasterocksarebrieflypresentedwithkeyresults.Theseprovidethepropertiesusedforthenumericalanalysesthatfollow.Acrosssectionofaportionofthetailingsimpoundmentcontaininganinclusionisthensimulatedusingafiniteelementcode.ThenumericalcalculationsshowtheextentoftheWRIinfluenceontailingsconsolidation.Additionalresultsillustratetheeffectofthemostimportantfactors.RÉSUMÉLaco-dispositiond™inclusionsderochesstériles(IRS)àl™intérieurd™unparcàrésidusconsisteàplacerstratégiquementlesIRSàl™intérieurduparcdurantsonopérationdemanièreàformerdescellulesinternes.Danscetarticle,lesauteursanalysentleseffetsdedrainagedusauxinclusionssurlaconsolidationdesrésidusdurantleremplissagedubassinàl™aidededonnéesexpérimentalesetdesimulationsnumériques.Lesessaisontfournilespropriétésdesrésidusetdesrochesstérilesutiliséesdanslesanalysesnumériques.Unesectionduparcàrésiduscontenantuneinclusionaétésimuléeparlaméthodedesélémentsfinis.Lescalculsnumériquesmontrentl™ampleurdel™influencedel™inclusionsurlaconsolidationdesrésidus.Desrésultatsadditionnelsillustrentl™effetdedifférentsfacteurs.1INTRODUCTIONSecurestorageoftailingsfromhardrockminescanbequitechallengingbecauseoftheircomplexproperties,1990;Aubertinetal.2002;Bussière2007).Amodifieddisposaltechniquehasbeenproposedtoreducethegeotechnicalandgeo-environmentalrisksassociatedwiththeconventionalsurfacestorageofminewastes.Thisnovelapproachconsistsinplacingwasterockinclusions(WRI)insidethetailingsimpoundmenttoformcompartments(orcells)inwhichthetailingsarestored(Figure1).Thisreduces,oreliminateinsomecases(forundergroundminesespecially),theneedtostoreseparatelywasterocksandtailings.Suchinclusionsofferpreferentialdrainagepathwaystodissipatetheexcessporewaterpressureduetoprogressivefilling,asthehydraulicconductivityofwasterocksisaboutthreeordersofmagnitudehigherthanthatoftailings.Wasterockinclusionscanthusincreasetheconsolidationrate,densityandshearresistanceoftailings.Thiseffectissomewhatsimilartotheaccelerationofclayeysoilsconsolidationbyhorizontaldrainageusingverticaldrains(Barron1948;Hansbo1981;IndraratnaandRedana1997;Leo2004;Tanetal.2008).Thehigherstiffnessandshearstrengthofwasterockinclusionsalsoserveasreinforcement,andthesecouldsignificantlyreducetheriskofinstabilityortheamountoftailingsreleasedinthecaseofabreach(JamesandAubertin2010,2012).Figure1:Schematicillustrationofatailingsimpoundmentwithwasterockinclusions(afterJamesandAubertin2010)Thistypeofco-disposalofwasterocksandtailingsisarecentadditiontotheoptionsthatexistforminewastemanagement(JamesandAubertin2010),andassuchitconstitutesanewresearcharea.Workontailingstestedonaseismicsimulator(Pépinetal.2012)andconceptualnumericalmodeling(Jahouaretal.2011;JamesandAubertin2012;Jamesetal.2013)havedemonstratedsomeoftheadvantagesoftheapproach,whichisnow
Access this article:
Canadian Geotechnical Society members can access to this article, along with all other Canadian Geotechnical Conference proceedings, in the Member Area. Conference proceedings are also available in many libraries.
Cite this article:
Frédérick L. Bolduc; Michel Aubertin (2013) Analysing the effects of waste rock inclusions on tailings consolidation: Laboratory tests and modeling of the large scale in situ behavior in GEO2013. Ottawa, Ontario: Canadian Geotechnical Society.
@article{GeoMon2013Paper116,author = Frédérick L. Bolduc; Michel Aubertin,title = Analysing the effects of waste rock inclusions on tailings consolidation: Laboratory tests and modeling of the large scale in situ behavior,year = 2013}