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CHAPTER TWO
SOIL STRENGTH BEHAVIOURWEEK FOUR – SIXDownload all notes materials of ECG303 at ;
i-Learn Portal of UiTM – hairol anuar haron
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Learning outcome
At the end of the lectue! "tudent "hould #e $#le to unde"t$nd%
• &e'ne the conce(t of total $nd efective stresses! pore pressure $nd excess pore pressure )*O+!,O+-
• E.(l$/n the conce(t of riction model $nd "o/l shearstrength0 ohr!Coulom" ailure theor#! shear strengthparameters of "o/l" )*O+!,O+-
•Illu"t$te the shear strength parameters of "o/l" – "he$ #o.$nd t/$./$l te"t )*O+!,O+-
• &e1elo( the "te""2"t$/n el$t/on"h/(" $nd e1$lu$te the f$/lueen1elo(e – stress path u"/n3 p!$ diagram )*O4!,O5-
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O%TL&'E O( PRE)E'TAT&O' 6 7 8 9
40: Intoduct/on $nd O1e1/e
40+ &e'n/t/on of Sten3th! She$ Sten3th $nd theF/ct/on &ete?/n$t/on of SHEAR STRENGTH ,o(et/e"
of So/l"40@ *o?($/"on #eteen &IRE*T SHEAR BOX TEST$nd TRIAXIAL SHEAR TEST
40 T(e of T/$./$l Te"t
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*+, &ntroduction andOvervie-
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Wh "o/l" f$/l to (efo? /t" funct/onCC
It /" #ec$u"e of "o/l eo"/onC
&e3$d$t/on of "o/l ?$te/$l"C
Lo"" /n "ten3thC
Re?/nde fo? God $l2
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*+, &ntroduction andOvervie-Onl ?$te/$l" /th "ten3th c$n h$1e "lo(e" #ec$u"e "he$ "te""e"
$e eDu/ed to ?$/nt$/n $ "lo(e "tuctue
The "he$ "te""e" )7-! (e1ent coll$("e $nd hel( to "u((ot the3eotechn/c$l "tuctue )found$t/on"! et$/n/n3 $ll"! e$th "lo(e" $ndo$d #$"e"-
F$/lue /ll occu hen the "he$ "te"" e.ceed" the l/?/t/n3 "he$"te"" )"ten3th-
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Sten3th• /" the ?e$"ue of the ?$./?u? "te"" "t$te th$t c$n #e
/nduced /n $ ?$te/$l /thout /t f$/l/n3• c$n #e "t$ted $" co?(e""/1e "te"" ten"/le "te""
She$ Sten3th• /" the ?$./?u? 1$lue of "he$ "te"" th$t ?$ #e
/nduced /th/n /t" ?$"" #efoe the "o/l /eld"
She$ Sten3th of So/l• )hear strength "et-een a soil mass is due to the
development o rictional resistance "et-eenad.acent particles/ and anal#ses are "asedprimaril# on the rictional model
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*+0 1e2nition o )trength/ )hear)trength and the (riction odel
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• The foce t$n"?/tted #eteen to#od/e" /n "t$t/c cont$ct c$n #ee"ol1ed /nto to co?(onent"%2No?$l co?(onent! N
2She$ co?(onent! T 2#oth $e (e(end/cul$ to e$ch othe
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*+0 1e2nition o )trength/)hear )trength and the
(riction odel
• When "he$ "l/((/n3?o1e?ent t$e (l$ce$lon3 th/" "uf$ce the$t/o TN /ll h$1ee$ched $ l/?/t/n3 1$luete?ed the coec/ent off/ct/on ) μ-
T l/?/t J N
N t$n 8=Whee 8= /" def/ned $"
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*+0 1e2nition o )trength/)hear )trength and the
(riction odel
• A "u33e"ted ?ech$n/"? of f/ct/on$l e"/"t$nce /" th$t$t the tue (o/nt" of cont$ct the ($t/cle" #eco?e
loced to3ethe
• Fo "l/d/n3 to occu! /t" /" nece""$ fo the ?$te/$l to/eld loc$ll $t the (o/nt of cont$ct
• The tue cont$ct $e$ #eteen the 3$/n" ?$ #e 1e
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*+* Concept o Total )tress 345and Eective )tress 3465
*on"/de $nele?ent of $saturated
soil "u#ectedto $ normalstress 345! $"/n the '3ue0
Ste"" 345 is called Total )tress $nd foeDu/l/#/u? )Neton=" th/d l$- the stressesin the soil must "e e$ual and opposite to
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*+* Concept o Total )tress 345and Eective )tress 3465
• Re"/"t$nce to 4! /" (o1/ded # $ co?#/n$t/onof the "te""e" fo? the "ol/d c$lled efectivestress 3465 $nd fo? (oe $te /n the (oe"!
c$lled pore pressure 3u5+
• Thu"; 6 6= u 6= 6 – u
• Th/" eDu$t/on /" c$lled the principle oefective stress! '"t eco3n/Med # TeM$3h/)+52+5-
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*+* Concept o Total )tress 345and Eective )tress 3465
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*+* Concept o Total )tress 345and Eective )tress 3465
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*+* Concept o Total )tress 345and Eective )tress 3465
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(ailure )urace – The "o/l 3$/n" "l/de o1ee$ch othe $lon3 the f$/lue "uf$ce! nocu"h/n3 of /nd/1/du$l 3$/n"
At f$/lue! shear stress )7- $lon3 the f$/lue"uf$ce e$che" the shear strength )7f -
*+7 )hear (ailure
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• The strength envelopes /" $ 3$(h/c$le(e"ent$t/on of $ ($t/cul$ l/?/t/n3 cond/t/onof shear stress 3859normal stress 345 $t/o
• The f$/lue en1elo(e /" non $" the ohr!Coulom" ailure envelope
• The f$/lue en1elo(e /" $ cu1ed l/ne! #ut fomost soil mechanics pro"lems! /t /" "uc/entto $((o./?$te the "he$ "te"" on the f$/lue(l$ne $" $ linear unction of the no?$l "te""
• The l/ne$ funct/on /" non $" Coulom"s La-+
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*+7+0 )hear (ailure : ohr!Coulom" (ailure Criterion
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*+7+* )hear (ailure : ohr!Coulom" (ailure Envelope
7f /" the ?$./?u? "he$ "te"" the "o/l c$n t$e
/thout f$/lue! unde no?$l "te"" of 6)hear
strengthcon"/"t of toco?(onent %cohesive $ndrictional
C $nd ; $e?e$"ue" of"he$ "ten3th0H&
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T(/c$l 1$lue" of /nten$l $n3le of f/ct/on! φ= $e 3/1en/n t$#le #elo
Soil type φ’ (deg)
Sand: rounded grainsLoose 27-0
!edi"m 0-#
$ense #-%
Sand: angular grains
Loose 0-#
!edi"m #-0
$ense 0-#
Gravel with some sand -%
Silts 2'-# 19
*+7+* )hear (ailure : ohr!Coulom" (ailure Envelope
3angle o riction/ 5
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•
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ormal stress ind"ced are σy
and σx *here σy + σx, So this
have ca"se shear τ.
Inclination of failureplane in soil withmaor principal plane
*+7+7 )hear (ailure : ohr Circleand (ailure Envelope
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*+7+7 )hear (ailure : ohr Circleand (ailure Envelope
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*+7+7 )hear (ailure : ohr Circleand (ailure Envelope
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+ + :Circle in Terms o Total)tress 345 and Eective
)tress 3465
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+ + :Envelopes in Terms oTotal )tress 345 and
Eective )tress 3465
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!ohr"s circle and failureen#elope
• σ'1 = major principal stress• σ'3 = minor principal stress• he failure plane ‘ef’ ma!es an
an"le # $ith the major principal plane
• o %etermine the an"le # an% therelationship bet$een major an%minor principal stress
• ‘fgh’ is the failure envelope%efine b& the coulomb la$relationship
•t can be sho$n that ‘bad’ =# = 0 * φ=! o
9 >@ φ=4
*+7+> )hear (ailure : Anal#sis o)tress using ohr6s Circle
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*+7+> )hear (ailure : Anal#sis o)tress using ohr6s Circle
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*+7+> )hear (ailure : Anal#sis o)tress using ohr6s Circle
)+,-tan()+,-(tan31 φ φ σ σ +++= c
)+,-tan()+,-(tan13 φ φ σ σ −−−= c
* = 1 t i ti )HEAR
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• Te"t h/ch c$n #e c$/ed out /n thel$#o$to – SHEAR BOX TEST
– TRIAXIAL TEST• Uncon"ol/d$ted Und$/ned Te"t ! UU
• *on"ol/d$ted Und$/ned Te"t! *U
•
*on"ol/d$ted &$/ned Te"t! *&
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*+= 1etermination o )HEAR)TRE'
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• The te"t /" $l"o non $"direct9simple "he$ te"t #ec$u"ethe no?$l "he$ "te"" on thef$/lue (l$ne /" ?e$"ued d/ectl0
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*+=+0 1etermination o )HEAR)TRE'
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*+=+0 1etermination o )HEAR)TRE'
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Shear box *ith alignment scre*s
*+=+0 1etermination o )HEAR)TRE'
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33Sample reparation
*+=+0 1etermination o )HEAR)TRE'
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lace the shear box "nder the load cell
*+=+0 1etermination o )HEAR)TRE'
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35.lign the load cell
*+=+0 1etermination o )HEAR)TRE'
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.d/"st the L$1 to complete contact
*+=+0 1etermination o )HEAR)TRE'
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lamp the shear box so that only the lo*er halfmoves,
3"n the test by applying a vertical load
*+=+0 1etermination o )HEAR)TRE'
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• She$ "l/( occu" o /" en1/"$3ed(predicted) $lon3 $ de'n/te "l/("uf$ce
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%v = vertical %isplacement
%h = hori.ontal %isplacement
*+=+0 1etermination o )HEAR)TRE'
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*+=+0 1etermination o )HEAR)TRE'
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*+=+0 1etermination o )HEAR)TRE'
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*+=+0 1etermination o )HEAR)TRE'
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• Advantages – She$ $nd no?$l "te""e" ?e$"ued d/ectl0
– No?$l "te"" con"t$nt thou3hout the te"t0
– The te"t /" "/?(le $nd f$"t fo 3$nul$ "o/l"
– Volu?e ch$n3e" $e e$"/l ?e$"ued0
– U"/n3 $ e1e"/#le "he$ #o. l$3e d/"(l$ce?ent c$n #e$ch/e1ed! thu" en$#l/n3 ?e$"ue?ent of e"/du$l "ten3th0
– A" the #$"/c (/nc/(le /" e$" to unde"t$nd /t c$n #ee.tended to 3$1ell "o/l! h/ch ould #e ee e.(en"/1e to
te"t # othe ?ethod" 42
*+=+0 1etermination o )HEAR)TRE'
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• 1isadvantages – It /" d/cult to contol the d$/n$3e of $te fo? the
"o/l
– The d/"t/#ut/on of "he$ "te"" o1e the (l$ne of f$/lue/" $""u?ed to #e un/fo?! #ut /n f$ct /t /" not
–
Not (o""/#le to contol d$/n$3e fo? the "$?(le o to?e$"ue the (oe (e""ue /th/n the "$?(le0 Theefoe! onl tot$l "te"" ?e$"ue?ent" c$n #e ?$de
– The no?$l "te"" c$nnot e$"/l #e 1$/ed du/n3 te"t"43
*+=+0 1etermination o )HEAR)TRE'
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• T/$./$l /" the ?o"t el/$#le ?ethod" $1$/l$#le fodete?/n/n3 "he$ "ten3th ($$?ete"
• So/l "(ec/?en $#out 5?? /n d/$?ete $nd Q?? lon3
/" 3ene$ll u"ed
• S(ec/?en /" enc$"ed # $ th/n u##e ?e?#$ne $nd(l$ced /n"/de $ (l$"t/c cl/nd/c$l ch$?#e th$t u"u$ll'lled /th $te
• The "(ec/?en /" "u#ected to $ con'n/n3 (e""ue #co?(e""/on of the u/d /n the ch$?#e
• To c$u"e "he$ f$/lue! one ?u"t $((l $./$l "te""thou3h $ 1et/c$l lo$d/n3 $?(
44
*+=+* 1etermination o )HEAR)TRE'
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* = * 1etermination o )HEAR
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• Principle Plane is the plane that is acte% upon b& a normal
stress onl&/ o shear stress present on a principal plane/
• Principal stress is the normal stress actin" on a principal plane/
• σ1 an% σ3 are !no$n as the major an% minor principal stresses
respectivel&/
*+=+* 1etermination o )HEAR)TRE'
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*+=+* 1etermination o )HEAR)TRE'
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• n triaial test2 failure plane is not pre%etermine%/• ailure occurs on the plane $here stress s&stem is most
critical/
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• he test is repeate% for several %ifferent values of cell pressureσ
3 an% the correspon%in" values of σ
1at failure foun% in each
case/
• his enables a set (at least 3) of 4ohr5s circles to be %ra$n/
*+=+* 1etermination o )HEAR)TRE'
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*+> Comparison "et-een 1irect )hear?ox Test and Triaxial )hear Test
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* T T i i l T t
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*+ T#pe o Triaxial Tests
* T T i i l T t
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*+ T#pe o Triaxial Tests
* T T i i l T t
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• A 3entle e?/nde
–
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45"ipment for the
triaxial test,
Sample preparation
*+ T#pe o Triaxial Tests
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* T T i i l T t
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Unconsolidated-undrained test/• Th/" te"t /" (efo?ed /th the d$/n 1$l1e clo"ed fo $ll (h$"e" of the te"t0• A./$l lo$d/n3 /" co??enced /??ed/$tel $fte the ch$?#e (e""ue σ5 /"
"t$#/l/Med0
Consolidated-undrained test!• In th/" te"t! d$/n$3e o con"ol/d$t/on /" $lloed to t$e (l$ce du/n3 the
$((l/c$t/on of the con'n/n3 (e""ue σ50• Lo$d/n3 doe" not co??ence unt/l the "$?(le ce$"e" to d$/n )o con"ol/d$te-0• The $./$l lo$d /" then $((l/ed to the "(ec/?en! /th no $tte?(t ?$de to
contol the fo?$t/on of e.ce"" (oe (e""ue0• Fo th/" te"t! the d$/n 1$l1e /" clo"ed du/n3 $./$l lo$d/n3! $nd e.ce"" (oe
(e""ue" c$n #e ?e$"ued0
Consolidated-drained test
• In th/" te"t! the d$/n 1$l1e /" o(ened $nd /" left o(en fo the du$t/on of thete"t! /th co?(lete "$?(le d$/n$3e (/o to $((l/c$t/on of the 1et/c$l lo$d0
• The lo$d /" $((l/ed $t "uch $ "lo "t$/n $te th$t ($t/cle e$du"t?ent" /n the"(ec/?en do not /nduce $n e.ce"" (oe (e""ue0
• S/nce thee /" no e.ce"" (oe (e""ue tot$l "te""e" /ll eDu$l eect/1e"te""e"0
• Al"o the 1olu?e ch$n3e of the "$?(le du/n3 "he$ c$n #e ?e$"ued0
57
*+ T#pe o Triaxial Tests
*++0 T#pe o Triaxial Tests ! %%
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• W/th th/" ?ethod! the "he$ "ten3th /" ?e$"ued/th e"(ect to tot$l "te""
• The "o/l "(ec/?en )"u((o"ed "$tu$ted- /" not$lloed to con"ol/d$te! ?$/nt$/n" /t" o/3/n$l"tuctue $nd $te content! "o th$t /t" e"/"t$nceonl de(end" on the le1el of 3eo"t$t/c "te"" /n the'eld
• Te"t $e u"u$ll c$/ed out on thee "(ec/?en" ofthe "$?e "$?(le "u#ected to d/eent con'n/n3(e""ue
• ,o1/ded th$t the "o/l /" full "$tu$ted! theeect/1e "te"" $t f$/lue /" the "$?e fo e$ch te"t
• The
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*++0 T#pe o Triaxial Tests ! %%
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• U"u$ll conducted on cl$" "(ec/?en"$nd de(end" on $ 1e /?(ot$nt"ten3th conce(t fo cohe"/1e "o/l" /f the"o/l /" full "$tu$ted
• The $dded $./$l "te"" $t f$/lue /"($ct/c$ll the "$?e e3$dle"" of thech$?#e con'n/n3 (e""ue
• So th$t! the f$/lue en1elo(e fo the tot$l
"te""
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#pTest (ailure Envelope
*++* T#pe o Triaxial Tests ! C%
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• W/th th/" te"t ?ethod the "he$ "ten3th/" ?e$"ued /n te?" of eect/1e "te""
• At le$"t thee "(ec/?en" $e $lloed tocon"ol/d$te )to ch$n3e /t" "tuctue $nd$te content- $t d/eent le1el ofcon'n/n3 (e""ue #efoe f$/lue
• &ue to the f$ct th$t "he$ "ten3th/nce$"e! $/"/n3 the eect/1e "te""e"!the *oulo?#=" ?odel c$n #e $((l/ed /nte?" of eect/1e "te""
• &u/n3 the f$/lue "t$3e the "(ec/?en /"not $lloed to d$/n $nd (oe (e""ue /"?e$"ued! "o th$t the eect/1e "te"" /"c$lcul$ted $" the d/eence #eteen the
tot$l "te"" $nd the (oe (e""ue62
#pTest
*++* T#pe o Triaxial Tests ! C%
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•
Total Stress7 cu 6n t$nφu
•
Eective Stress7 c= 6n= t$nφ=
•
Pore pressure u 6+ 2 6+= o 65 – 65=
63
#pTest
pore pressuredevelops
during shear aster thanC1 3preerred-a# to 2nd c6and ;6
*++* T#pe o Triaxial Tests ! C%
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64
,otal and effecti#e stress failure en#elope from -. tests
#pTest (ailure Envelope
*++* T#pe o Triaxial Tests ! C% Test
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65,otal stress failure en#elope from -. test in o#erconsolidated clay
#p(ailure Envelope or CLAD )O&L)
Example 0
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Example 0
A *U te"t on $ no?$ll con"ol/d$tedcl$ /elded the follo/n3 e"ult"%
σ3 = 100 !Pa
7eviator stress = 10 !Pa
Pore pressure2 (8u%)f = 90 !Pa
Calculate the consoli%ate% un%raine% friction an"lean% the consoli%ate% %raine% friction an"le
66
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Example 0
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A3$/n!
σ=3 = σ3 - )ud-f +::2Q: 5: ,$
σ=1 = σ1 - )ud-f 5+:2Q: 4>: ,$FRO< SLI&E NO0 5
Fo no?$ll con"ol/d$ted cl$ /th c=:;
0FRO< SLI&E NO0 + @5
6=+ 6=5 t$n4)>@ φ=4-4>: 5: t$n4)>@ φ=4-
φ= @+
68
Example 0
*++7 T#pe o Triaxial Tests ! C1
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• Th/" te"t ?ethod /" "/?/l$ to *U te"t$" the "he$ "ten3th c$n #e el$tedto the $((l/ed le1el of "te""
• At le$"t thee "(ec/?en" $e $lloedto con"ol/d$te $t d/eent le1el of
con'n/n3 (e""ue
• The f$/lue "t$3e /" c$/ed out 1e"lol to (e1ent the /nce$"e of (oe(e""ue /n"/de the "(ec/?en! th$t /"$lloed to d$/n
• The tot$l $nd eect/1e "te""e" $ethe "$?e
•
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The "$?(le /" (l$ced #eteen (oou" d/"c" $nd/n"eted /n the t/$./$l $(($$tu"0
The cell (e""ue /" $((l/ed $nd the $(($$tu" leftunt/l the /nduced (oe $te (e""ue h$"
d/""/($ted! u"u$ll $fte 4>h"0
The de1/$to "te"" 6+ 2 65 /" then $((l/ed $t "uch$ "lo $te th$t u= doe" not de1elo(0
It u"u$ll t$e" #eteen 4 d$" $nd 4 ee" toc$ out $ "/n3le d$/ned t/$./$l te"t0 )Th/" te"t /"c$lled slo- triaxial test-
70
#pTest
*++7 T#pe o Triaxial Tests ! C1 Test
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71
in 'ORAL Consolidated CLAD
2/6/3 ,ype of ,ria)ial ,ests - ,est
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72
in -onsolidated -(
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Example *
Fo no?$ll con"ol/d$ted cl$! the e"ult" of $d$/ned t/$./$l te"t $e $" follo"%
*h$?#e con'n/n3 (e""ue!σ3 + l#/n4
&e1/$to "te"" $t f$/lue!σ1-σ3 4@ l#/n4
$- F/nd the $n3le of f/ct/on
#- &ete?/ne the $n3le!9 th$t the f$/lue (l$ne?$e" /th the ?$o (/nc/($l (l$ne
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74
(nswer
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75
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Example 7
The eDu$t/on of the eect/1e "te""f$/lue en1elo(e fo normall#
consolidated cla#e# "o/l /" 7f 6=t$n 25.
A d$/ned t/$./$l te"t $" conducted
/th the "$?e "o/l $t $ ch$?#econ'n/n3 (e""ue of :N?40
*$lcul$te the de1/$to "te"" $tf$/lue0
76
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An"e
Fo no?$ll con"ol/d$ted cl$! c=:!thu"
6+= 65= t$n4)>@ φ=4-φ=4@
6+= : t$n4)>@ 4@4- +QN?4
So! )6d-f 6=+26=5 +Q2:
++QN?4
77
E l >
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Example >
The follo/n3 d$t$ ee o#t$/ned fo? $n und$/nedt/$./$l te"t on $ "e/e" of "$tu$ted "o/l "$?(le"
&ete?/ne the 1$lue" of the $(($ent cohe"/on! c $ndthe $n3le of /nten$l f/ct/on! φ
/-W/th e"(ect to tot$l "te""e"
//- W/th e"(ect to eect/1e "te""e"
78
)oil sample 0 * 7
*ell (e""ue ),$- +@: 4@: 5@:
,oe (e""ue ),$- @: +:: +@:
&e1/$to "te"" ),$- +@: 5:: >::
Ans-er
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Ans-erCell pressure 0>, *>, 7>,
,oe (e""ue @: +:: +@:&e1/$to "te"" +@: 5:: >::
σ1 = σ3 * σ% 5:: @@: Q@:
σ3' = σ3 : u +:: +@: 4::
σ1' = σ1 - u 4@: >@: ::
79
i) 6rom the graph of total stress parametersc" 2#φ" 8% ͦ
ii) 6rom the graph of the effective stress parametersc’ 20φ’ 2' ͦ
*+ )tress Path using p!$
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Learning outcome 3W5At the end of the lectue! "tudent"hould #e $#le to unde"t$nd%
• Ste""2"t$/n el$t/on"h/(" $ndde/1$t/on of f$/lue en1elo(e – "te""($th u"/n3 (2D d/$3$?
1iagram
*+ )tress Path using p!$i
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• Re"ult" of t/$./$l te"t" c$n #e e(e"ented # d/$3$?c$lled stress paths
• Ste"" ($th /" $ 3$(h/c$l e(e"ent$t/on of the locu" of"te""e" on $ #od
• It /" $ l/ne th$t connect" $ "e/e" of (o/nt"! e$ch of h/che(e"ent" $ "ucce""/1e "te"" "t$te e.(e/enced # $ "o/l"(ec/?en du/n3 the (o3e"" of $ te"t
• Thee $e "e1e$l $" /n h/ch "te"" ($th c$n #e d$n$nd (lot" D= $3$/n"t (= )hee (= $nd D= $e thecoordinates of the top of the ohr6s circle- /" one ofthe?
1iagram
*+ )tress Path using p!$i
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1iagram
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*+ )tress Path using p!$1i
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1iagram
*+ )tress Path using p!$1i
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• *on"/de $ no?$ll con"ol/d$ted cl$ "(ec/?en"u#ected to $n /"oto(/c$ll consolidated-drained
t/$./$l te"t )'3 ++04-
• The el$t/on"h/(" fo (= $nd D= $e $" follo"%
• At the "eginning of the $((l/c$t/on of de1/$to "te""/ 460
467 47! "o
• Fo th/" cond/t/on (= $nd D= /ll (lot $" $ (o/nt )th$t /" I’ /n
'3 ++04-
• At "o?e othe t/?e du/n3 de1/$to "te"" $((l/c$t/on! 6=+
6=5 6d 65 6d ; 6=5 65
• The
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•
If the"e 1$lue" of (= $nd D= ee (lotted /n '3++04! the ould #e e(e"ented # (o/nt D= $tthe to( of the @o /ththe ho/Mont$l
• ,o/nt & e(e"ent" the f$/lue cond/t/on of the "o/l"(ec/?en /n the te"t
1iagram
*+ )tress Path using p!$1i
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• L/ne !" /" the f$/lue en1elo(e fo the "o/l• A ?od/'ed f$/lue en1elo(e c$n no #e
de'ned # l/ne OF=
•
Th/" ?od/'ed l/ne /" co??onl c$lled theK f l/ne $nd c$n #e e.(e""e" $"
;here < = the an"le that the mo%ifie% failure
envelopes ma!es $ith the hori.ontal
1iagram
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• The el$t/on"h/( #eteen $n3le" φ $nd
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• F/3ue #elo "ho" $ D=2(= (lot fo $no?$ll con"ol/d$ted cla# "(ec/?en"u#ected to $n /"oto(/c$llconsolidated-undrained t/$./$l
te"t
1iagram
*+ )tress Path using p!$1i
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• At the #e3/nn/n3 of the $((l/c$t/on ofde1/$to "te""! 6=+ 6=5 650 hence (=
6=5 $nd D=:
• Th/" el$t/on"h/( /" e(e"ented # (o/nt I
• At "o?e othe "t$3e of the de1/$to "te""$((l/c$t/on! 6=+ 65 6d – Δud an% 6=5 65 –
Δud2 so
1iagram
*+ )tress Path using p!$1iagram
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• The (eced/n3 1$lue" of (= $nd D= /ll (lot $"(o/nt U= /n '3 ++05: (o/nt" "uch $" U==e(e"ent 1$lue" of (= $nd D= $" the te"t(o3e""e"0
• The eect/1e "te"" ($th fo $ con"ol/d$ted2und$/ned te"t c$n #e 3/1en # the cu1e IU=U
• L$?#e )+>- (o(o"ed $ techn/Due toe1$lu$te the el$"t/c $nd con"ol/d$t/on
"ettle?ent" of found$t/on" on cl$ "o/l" #u"/n3 the "te"" ($th" dete?/ned /n th/"?$nne
1iagram
*+ )tress Path using p!$1iagram
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• Su??$ of the (ocedue fo (lott/n3 "te"" ($th"
+0 &ete?/ne the lo$d/n3 cond/t/on" d$/ned o und$/nedo #oth
40 *$lcul$te the /n/t/$l lo$d/n3 1$lue"! ( $nd D
50 Set u( 3$(h of (= $" the $#"c/""$ $nd D= $" theod/n$te0 ,lot the /n/t/$l 1$lue" )(=! D=-
>0 &ete?/ne the /nce$"e /n "te""! 6d
@0 *$lcul$te the /nce$"e /n "te"" /n1$/$nt"
0 *$lcul$te the cuent "te"" /n1$/$nt"
Q0 ,lot the cuent "te"" /n1$/$nt" )(=! D=-
0 *onnect the (o/nt" /dent/f/n3 eect/1e "te""e" $nd dothe "$?e fo tot$l "te""e"
0 Re(e$t /te?" > to fo the ne.t lo$d/n3 cond/t/on
1iagram
E.$?(le
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E.$?(le Q
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E.$?(le
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E.$?(le
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1o ma@e a lot o practice on thetutorial $uestions+
Practice ma@es "etter+
End o Wee@ G End o Topic *Wee@ % Flo of W$te Thou3h So/l0
W$""l$? Th$n You0
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