Geotechnical engineering of dams

1374 Pages·2014·242.909 MB·English

by  Robin Fell, Patrick MacGregor, David Stapledon, Graeme Bell, Mark Foster

Fell
MacGregor
Stapledon
Bell
Foster
Geotechnical Engineering of Dams, 2nd edition provides a comprehensive text on
the geotechnical and geological aspects of the investigations for and the design and
construction of new dams and the review and assessment of existing dams. The main
emphasis of this work is on embankment dams, but much of the text, particularly
those parts related to geology, can be used for concrete gravity and arch dams.
EG
All phases of investigation, design and construction are covered. Detailed descriptions ne
go
are given from the initial site assessment and site investigation program through to the it
preliminary and detailed design phases and, ultimately, the construction phase. The ne
ec
assessment of existing dams, including the analysis of risks posed by those dams, is
eh
also discussed. This wholly revised and significantly expanded 2nd edition includes rn
i
a lengthy new appendix on the assessment of the likelihood of failure of dams by ni
c
internal erosion and piping. ga

ol
This valuable source on dam engineering incorporates the 200+ years of collective f

experience of the authors in the subject area. Design methods are presented in D
combination with their theoretical basis, to enable the reader to develop a proper a
m
understanding of the possibilities and limitations of a method. For its practical,
well-founded approach, this work can serve as a useful guide for professional dam s
engineers and engineering geologists and as a textbook for university students.

Photograph front:
Hinze Dam at completion of Stage 3 construction.
Courtesy of The Hinze Dam Alliance (comprising Seqwater, SKM, Thiess and URS).
Geotechnical
Engineering of Dams
2nd edition
2nd Robin Fell
edition Patrick MacGregor
David Stapledon
Graeme Bell
Mark Foster
an informa business
Geotechnical Engineering of Dams,
2nd edition
TThhiiss ppaaggee iinntteennttiioonnaallllyy lleefftt bbllaannkk
Geotechnical Engineering of Dams,
2nd edition
Robin Fell
Emeritus Professor,School of Civil and Environmental Engineering,
University of New SouthWales,Sydney,Australia
Patrick MacGregor
Consulting Engineering Geologist,Australia
David Stapledon
Consulting Engineering Geologist,Australia
Graeme Bell
Consulting Dams Engineer,Australia
Mark Foster
Senior Principal Dams Engineer,URSAustralia,Sydney, Australia
Coverillustration:HinzeDamatcompletionofStage3construction.CourtesyofTheHinze
DamAlliance(comprisingSeqwater, SKM,ThiessandURS).
CRCPress/BalkemaisanimprintoftheTaylor&FrancisGroup,aninformabusiness
©2015Taylor&FrancisGroup,London,UK
TypesetbyMPSLimited,Chennai,India
PrintedandBoundbyCPIGroup(UK)Ltd,Croydon,CR04YY.
Allrightsreserved.Nopartofthispublicationortheinformationcontained
hereinmaybereproduced,storedinaretrievalsystem,ortransmittedinany
formorbyanymeans,electronic,mechanical,byphotocopying,recordingor
otherwise,withoutwrittenpriorpermissionfromthepublisher.
Althoughallcareistakentoensureintegrityandthequalityofthispublication
andtheinformationherein,noresponsibilityisassumedbythepublishersnor
theauthorforanydamagetothepropertyorpersonsasaresultofoperation
oruseofthispublicationand/ortheinformationcontainedherein.
LibraryofCongressCataloging-in-PublicationData
Fell,Robin.
Geotechnicalengineeringofdams/RobinFell,Emeritus,Professor,SchoolofCivilandEnvironmental
Engineering,UniversityofNewSouthWales,Sydney,Australia,PatrickMacGregor,Consulting
EngineeringGeologist,Australia,DavidStapledon,ConsultingEngineeringGeologist,Australia,
GraemeBell,ConsultingDamsEngineer,Australia,MarkFoster,SeniorPrincipalDamsEngineer,
URSAustralia,Sydney,Australia.–2ndedition.
pagescm
Includesbibliographicalreferencesandindex.
ISBN978-1-138-00008-7(hardback)–ISBN978-0-203-38731-3(ebook)
1. Dams–Designandconstruction. I.Title.
TC540.F45 2014
627’.8–dc23
2014040176
Publishedby: CRCPress/Balkema
P.O.Box11320,2301EHLeiden,TheNetherlands
e-mail:[email protected]
www.crcpress.com–www.taylorandfrancis.com
ISBN:978-1-138-00008-7(Hbk)
ISBN:978-0-203-38731-3(eBookPDF)
Table of contents
AuthorBiographies xxxiii
1 Introduction 1
1.1 Outlineofthebook 1
1.2 Typesofembankmentdamsandtheirmainfeatures 2
1.3 Typesofconcretedamsandtheirmainfeatures 6
2 Keygeologicalissues 11
2.1 Basicdefinitions 11
2.2 Typesofanisotropicfabrics 12
2.3 Defectsinrockmasses 12
2.3.1 Joints 14
2.3.2 Shearedandcrushedzones(faults) 14
2.3.3 Soilinfillseams(orjustinfillseams) 15
2.3.4 Extremelyweathered(oraltered)seams 15
2.3.5 Theimportanceofusingtheabovetermstodescribedefects
inrock 15
2.4 Defectsinsoilmasses 16
2.5 Stressesinrockmasses 17
2.5.1 Probablesourceofhighhorizontalstresses 18
2.5.2 Stressreliefeffectsinnaturalrockexposures 20
2.5.3 Effectsinclaystonesandshales 20
2.5.4 Specialeffectsinvalleys 21
2.5.5 Rockmovementsinexcavations 24
2.6 Weatheringofrocks 26
2.6.1 Mechanicalweathering 26
2.6.2 Chemicaldecomposition 26
2.6.3 Chemicalweathering 27
2.6.3.1 Susceptibilityofcommonmineralsto
chemicalweathering 29
2.6.3.2 Susceptibilityofrocksubstancesto
chemicalweathering 30
2.6.4 Weatheredrockprofilesandtheirdevelopment 31
2.6.4.1 Climateandvegetation 32
2.6.4.2 Rocksubstancetypesanddefecttypesand
pattern 32
vi Table of contents
2.6.4.3 Timeanderosion 38
2.6.4.4 Groundwaterandtopography 39
2.6.4.5 Featuresofweatheredprofilesnear
valleyfloors 40
2.6.5 Complicationsduetocementation 42
2.7 Chemicalalteration 43
2.8 Classificationofweatheredrock 43
2.8.1 Recommendedsystemforclassificationofweathered
rocksubstance 44
2.8.2 Limitationsonclassificationsystemsforweatheredrock 46
2.9 Rapidweathering 47
2.9.1 Slakingofmudrocks 47
2.9.2 Crystalgrowthinpores 48
2.9.3 Expansionofsecondaryminerals 48
2.9.4 Oxidationofsulphideminerals 48
2.9.4.1 Sulphideoxidationeffectsinrockfill
dams–someexamples 49
2.9.4.2 Possibleeffectsofsulphideoxidationin
rockfilldams 50
2.9.4.3 Sulphideoxidation–implicationsforsitestudies 51
2.9.5 Rapidsolution 51
2.9.6 Surfacefrettingduetoelectro-staticmoistureabsorption 51
2.10 Landslidingatdamsites 51
2.10.1 First-timeand“reactivated’’slides 53
2.10.1.1 Reactivatedslides 53
2.10.1.2 First-timeslides 53
2.10.2 Importanceofearlyrecognitionofevidenceofpastslope
instabilityatdamsites 53
2.10.3 Damsandlandslides:Someexperiences 54
2.10.3.1 TalbingoDam 54
2.10.3.2 ToomaDam 54
2.10.3.3 WungongDam 60
2.10.3.4 SugarloafDam 62
2.10.3.5 ThomsonDam 66
2.11 Stabilityofslopesaroundstorages 70
2.11.1 Vitalslopestabilityquestionsforthefeasibilityandsite
selectionstages 73
2.11.1.1 Mostvulnerableexistingorproposedproject
features,andpartsofstoragearea?–
Question1 73
2.11.1.2 Currentlyactiveorolddormantlandslides?–
Questions2and4to7 73
2.11.1.3 Areaswherefirst-timelandslidingmaybe
induced(Questions3to7) 75
2.11.1.4 Whatisthelikelypostfailurevelocityand
traveldistance? 76
2.11.1.5 Whatisthesizeofimpulsewaveswhich
maybecreated? 80
Table of contents vii
2.12 Watertightnessofstorages 80
2.12.1 Modelsforwatertightnessofstoragesinmanyareasof
non-solublerocks 80
2.12.2 Watertightnessofstorageareasformedbysolublerocks 83
2.12.3 Featureswhichmayformlocalzonesofhighleakage,from
anystoragearea 84
2.12.4 Watertightnessofstoragesunderlainbysoils 85
2.12.5 Assessmentofwatertightness 85
2.12.5.1 Storagesinnon-solublerockareas–assessment
ofwatertightness 85
2.12.5.2 Storagesinsolublerockareas–assessment
ofwatertightness 86
2.12.5.3 Storagesformedinsoils–assessment
ofwatertightness 87
2.12.6 Methodsusedtopreventorlimitleakagesfromstorages 88
3 Geotechnicalquestionsassociatedwithvarious
geologicalenvironments 89
3.1 Graniticrocks 89
3.1.1 Freshgraniticrocks,propertiesanduses 89
3.1.2 Weatheredgraniticrocks,properties,usesandprofiles 90
3.1.3 Stabilityofslopesingraniticrocks 91
3.1.4 Graniticrocks:checklist 91
3.2 Volcanicrocks(intrusiveandflow) 91
3.2.1 Intrusiveplugs,dykesandsills 92
3.2.2 Flows 93
3.2.2.1 Flowsonland 93
3.2.2.2 Underseaflows 96
3.2.3 Alterationofvolcanicrocks 97
3.2.4 Weatheringofvolcanicrocks 98
3.2.5 Landslidingonslopesunderlainbyweatheredbasalt 98
3.2.6 Alkali-aggregatereaction 99
3.2.7 Volcanicrocks(intrusiveandflow)checklistofquestions 99
3.3 Pyroclastics 100
3.3.1 Variabilityofpyroclasticmaterialsandmasses 100
3.3.2 Particularconstructionissuesinpyroclastics 102
3.3.3 Pyroclasticmaterials–checklistofquestions 105
3.4 Schistoserocks 105
3.4.1 Propertiesoffreshschistoserocksubstances 106
3.4.2 Weatheredproductsandprofilesdevelopedin
schistoserock 106
3.4.3 Suitabilityofschistoserocksforuseasfiltermaterials,
concreteaggregatesandpavementmaterials 108
3.4.4 Suitabilityofschistoserocksforuseasrockfill 108
3.4.5 Structuraldefectsofparticularsignificancein
schistoserocks 110
3.4.5.1 Minorfaultsdevelopedparallelandatacute
anglestothefoliation 110
viii Table of contents
3.4.5.2 Kinkbands 111
3.4.5.3 Mica-richlayers 113
3.4.6 Stabilityofslopesformedbyschistoserocks 114
3.4.7 Schistoserocks–checklistofquestions 114
3.5 Mudrocks 114
3.5.1 Engineeringpropertiesofmudrocks 115
3.5.2 Bedding-surfacefaultsinmudrocks 116
3.5.3 Slickensidedjointsorfissures 117
3.5.4 Weatheredproductsandprofilesinmudrocks 117
3.5.5 Stabilityofslopesunderlainbymudrocks 117
3.5.6 Developmentofunusuallyhighporepressures 118
3.5.7 Suitabilityofmudrocksforuseasconstructionmaterials 118
3.5.8 Mudrocks–checklistofquestions 120
3.6 Sandstonesandrelatedsedimentaryrocks 121
3.6.1 Propertiesoftherocksubstances 122
3.6.2 Suitabilityforuseasconstructionmaterials 122
3.6.3 Weatheringproducts 123
3.6.4 Weatheredprofileandstabilityofslopes 123
3.6.5 Sandstonesandsimilarrocks–listofquestions 126
3.7 Carbonaterocks 126
3.7.1 Effectsofsolution 127
3.7.1.1 Rockmassescomposedofdense,finegrained
rocksubstancescomprisingmorethan90%of
carbonate(usuallyCategoryO) 128
3.7.1.2 Rockmassescomposedofdensefinegrainedrock
substancecontaining10%to90%ofcarbonate
(usuallyCategoryO) 130
3.7.1.3 Rockmassescomposedofporous,lowdensity
carbonaterocksubstance(usuallyCategoryY) 131
3.7.2 Watertightnessofdamfoundations 132
3.7.2.1 Damswhichhaveexperiencedsignificant
leakageproblems 133
3.7.3 Potentialforsinkholestodevelopbeneathadam,reservoir
orassociatedworks 135
3.7.4 Potentialforcontinuingdissolutionofjointedcarbonate
rockindamfoundations 137
3.7.5 Potentialforcontinuingdissolutionofaggregatesof
carbonaterockparticlesandofpermeablecarbonate
substances(CategoryOcarbonate,ineachcase) 140
3.7.6 Discussion–potentialforcontinuingdissolutionof
carbonaterocksinfoundations 141
3.7.6.1 CategoryOcarbonaterocks 141
3.7.6.2 CategoryYcarbonaterocks 143
3.7.7 Potentialproblemswithfilters’composedof
carbonaterocks 143
3.7.7.1 CategoryOcarbonaterocks 143
3.7.7.2 CategoryYcarbonatematerials 145
Table of contents ix
3.7.8 Suitabilityofcarbonaterocksforembankmentmaterials 147
3.7.9 Suitabilityofcarbonaterocksforconcreteand
pavementmaterials 148
3.7.10 Stabilityofslopesunderlainbycarbonaterocks 148
3.7.11 Dewateringofexcavationsincarbonaterocks 151
3.7.12 Carbonaterocks–checklistofquestions 151
3.8 Evaporites 151
3.8.1 Performanceofdamsbuiltonrockscontaining
evaporites 152
3.8.2 Guidelinesfordamconstructionatsiteswhich
containevaporites 152
3.8.3 Evaporites–checklistofquestions 153
3.9 Alluvialsoils 154
3.9.1 Riverchanneldeposits 156
3.9.2 Open-workgravels 156
3.9.3 Oxbowlakedeposits 156
3.9.4 Floodplain,lacustrineandestuarinedeposits 157
3.9.5 Useofalluvialsoilsforconstruction 157
3.9.6 Alluvialsoils,listofquestions 157
3.10 Colluvialsoils 158
3.10.1 Occurrenceanddescription 158
3.10.1.1 Screeandtalus 158
3.10.1.2 Slopewashsoils 159
3.10.1.3 Landslidedebris 159
3.10.2 Propertiesofcolluvialsoils 160
3.10.2.1 Screeandtalus 160
3.10.2.2 Slopewash 160
3.10.2.3 Landslidedebris 160
3.10.3 Useasconstructionmaterials 161
3.10.4 Colluvialsoil–listofquestions 161
3.11 Lateritesandlateriticweatheringprofiles 162
3.11.1 Composition,thicknessesandoriginoflateritic
weatheringprofiles 162
3.11.2 Propertiesoflateriticsoils 163
3.11.3 Useoflateriticsoilsforconstruction 164
3.11.4 Karsticfeaturesdevelopedinlateriteterrain 164
3.11.5 Recognitionandinterpretationofsilcretelayer 165
3.11.6 Lateriticsoilsandprofiles–listofquestions 166
3.12 Glacialdepositsandlandforms 166
3.12.1 Glaciatedvalleys 167
3.12.2 Materialsdepositedbyglaciers 170
3.12.2.1 Propertiesoftillmaterials 174
3.12.2.2 Disruptedbedrocksurface
beneathglaciers 176
3.12.3 Glaciofluvialdeposits 177
3.12.4 Periglacialfeatures 179
3.12.5 Glacialenvironment–listofquestions 182