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gschedulesareofte
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give
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ycasesthescheduleispreparedbyaju
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tItishighlightedthatthee
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gperforma
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ttakesi
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classificatio
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te
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amorei
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gtrialpitti
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ed
62DEEPTRIALPITSTheexcavatio
ofdeeptrialpitsisofte
perceivedascumbersomea
ddifficulta
dtherefore
otco
sideredappropriatebydesig
e
gi
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ofdeeptrialpitsi
boulderclaysoilstodepthsofupto12misfeasibleusi
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rece
tyearsIGSLhasu
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edfromthesehascertai
lye
ha
cedthegeotech
icaldataa
dprovidedabetteru
dersta
di
gofthebulkpropertiesofthesoilsItisrecomme
dedthatthisworkbecarriedoutfollowi
gcompletio
ofthecablepercussio
boreholesa
drotarycoredrillholesThegrou
dwaterregimewithi
thecutareawillplaya
importa
trolei
gover
i
gthefeasibilityofexcavati
gdeeptrialpitsThei
stallatio
ofsta
dpipesa
dpiezometerswillgreatlyassisttheu
dersta
di
gofthegrou
dwaterco
ditio
she
cethepurposeofu
dertaki
gthisworklateo
i
thegrou
di
vestigatio
programme
fLargereprese
tativesamplesca
beobtai
edusi
gtre
chboxa
di
situshearstre
gthmeasuredo
blocksamplesThestabilityofthepitsidewallsa
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dwaterco
ditio
sca
alsobeestablisheda
dcomparedwithlevelsi
earbyboreholesta
dpipesorpiezometersOverapromi
e
tcutareaofsay500mthreedeeptrialpitsca
provei
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trialsFromavaluee
gi
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ga
drei
stati
gtheseexcavatio
sca
beeasilyrecoveredAprovisio
alsumca
beallocatedi
thegrou
di
vestigatio
a
dusedforthiswork
63HIGHQUALITYLARGEDIAMETERROTARYCOREDRILLINGThissysteme
tailstheuseoflargediameterrotarycoredrilli
gtech
iquesusi
gairmistorpolymergelflushTripletubecoredrilli
giscarriedoutthroughtheoverburde
soilswiththerecoveredmaterialheldi
aplasticcoreli
erCorerecoveryi
lowplasticityboulderclayhasbee
show
tobeextremelygoodtypicallyi
excessof90Thehighcorerecoverypermitsdetailede
gi
eeri
ggeor