direct shear test

TABLE OF CONTENTS NO. 1.0 2.0 3.0 4.0 ".0 %.0 (.0 +.0 ,.0 10.0

CONTENT

Introduction Objective Theory Background Equi!ent #rocedure$ &e$u't$ )a!'e *a'cu'ation i$cu$$ion *onc'u$ion &eerence

PAGES 2 2 2-3 3-4 4-" "-( +-, ,-10 10-11 11

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1.0 Introduction

The te$t i$ carried out on either undi$turbed $a!'e$ or re!o'ded $a!'e$. To aci'itate the re!o'ding uro$e/ a $oi' $a!'e !ay be co!acted at oti!u! !oi$ture content in a co!action !o'd. Then $eci!en or the direct $hear te$t cou'd be obtained u$ing the correct cutter rovided. 'ternative'y/ $and $a!'e can be 'aced in a dry $tate at a required den$ity/ in the a$$e!b'ed $hear bo.   nor!a' 'oad i$ a'ied to the $eci!en and the $eci!en i$ $heared acro$$ the redeter!ined horionta' 'ane beteen the to ha've$ o the $hear bo. ea$ure!ent$ o  $hear 'oad/ $hear di$'ace!ent and nor!a' di$'ace!ent are recorded. The te$t i$ reeated oe to or !ore identica' $eci!en$ under dierent nor!a' 'oad$. 5ro! the re$u't$/ the $hear  $trength ara!eter$ can be deter!ined.

2.0 Objective

To deter!ine the ara!eter o o $hear $trength o $oi'/ cohe$ion/ c and ang'e o riction/ 6. 6.

 3.0 Teor! B"c#$round

The gen genera era'' re'ati re'ation$ on$hi hi bet bete een en !a !ai!u i!u! ! $he $heari aring ng re$i$t re$i$tanc ance/ e/

Շ 

and nor! nor!a' a'

$tre$$/ 7n or $oi'$ can be rere$ented by the equation and knon a$ *ou'o!b8$ 9a:

τ   f  

=

c

+

σ  tan φ 

here: c

; cohe$ion/ cohe$ion/ hich hich i$ due due to interna' interna' orce$ orce$ ho'ding ho'ding $oi' artic' artic'e$ e$ toge together ther in a $o'id $o'id !a$$ <

; riction/ hich i$ due to the inter'ocking o the artic'e$ and the riction beteen the! hen $ubjected to nor!a' $tre$$

τf

=

$hearing re$i$tance o $oi' at ai'ure

σf

=

tota' nor!a' $tre$$ on ai'ure 'ane

The ricti riction on co! co!on onent ent$ $ increa increa$e $e ith ith increa$ increa$ing ing nor!a' nor!a' $tre$$ $tre$$ but the coh cohe$i e$ion on co!on co! onent ent$ $ re!ain re!ain$ $ con con$ta $tant. nt. I the there re i$ no nor!a' nor!a' $tre$$ $tre$$ the ricti riction on di$a di$aear ear$. $. Thi$ Thi$ 2

re'ation$hi $hon in the grah be'o. Thi$ grah genera''y aroi!ate$ to a $traight 'ine/ it$ inc'ination to the horionta' ai$ being equa' to the ang'e o $hearing re$i$tance o the $oi'/ < and it$ intercet on the vertica' =$hear $tre$$> ai$ being the aarent cohe$ion/ denoted by c.

?rah o )hear )tre$$ v$ @or!a' )tre$$

%.0 E&ui'(ent

1. )hear bo carriage. 2. 9oading ad. 3. #erorated 'ate. 4. #orou$ 'ate. ". &etaining 'ate. %. ?rea$e.

)hear bo carriage

9oading age

3

#erorated 'ate/ #orou$ 'ate/

?rea$e

&etaining 'at

).0 Procedure*

1. Interna' Interna' !ea$ure!ent !ea$ure!ent i$ i$ veriy by by u$ing vernier vernier ca'ier$. ca'ier$. The The 'ength o the the $ide$/ $ide$/ 9 and the overa'' deth/ B. 2. Ba$e Ba$e 'ate i$ ied ied in$ide in$ide the $hear $hear bo. Then Then orou orou$ $ 'ate i$ ut on the ba$e ba$e 'ate. 'ate. #erorated grid 'ate i$ itted over orou$ $o that the grid 'ate$ $hou'd be at right ang'e$ to the direction $hear.

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3. To To ha've$ ha've$ o the $hear $hear bo bo  i$ ied ied by !ea !ean$ n$ o iing iing $cre $cre$. $. 4. 5or 5or cohe cohe$i $ive ve $oi' $oi'$/ $/ the the $oi' $oi' $a! $a!'e 'e i$ tran tran$ $er er ro! ro! $qua $quare re $ec $eci! i!en en cutt cutter er to the the $hearbo by re$$ing don on the to grid 'ate. 5or $andy $oi'/ co!act $oi' in 'ayer$ to the required den$ity in $hear bo. ". ount the $hear $hear bo bo a$$e!b a$$e!b'y 'y on the 'oading 'oading ra!e. ra!e. %. The dia' dia' i$ i$ $et $et o the the rovin roving g ring ring to ero ero (. The 'oading 'oading yoke yoke i$ 'aced on the the 'oading 'oading ad and careu''y careu''y 'it 'it the han hanger ger onto th the e to o the 'oading yoke. +. The corr correct ect 'oad 'oading ing i$ a' a'ied ied to tthe he hanger hanger a ad. d. ,. *areu''y *areu''y the the $cre$ $cre$ c'a!ing c'a!ing the uer uer ha' ha' i$ re!oved re!oved to tthe he 'oer 'oer ha'. 10. The te$t i$ conducted by a'ying horionta' horionta' $hear 'oad to ai'ure. ai'ure. &ate $train $hou'd be 0.2!!A!in 11 11.. &eading$ o horionta' i$ recorded and orce dia' gauge$ at regu'ar interva'$. 12. *onduc *onductt te$ te$tt on three three ide identi ntica' ca' $oi' $oi' $a! $a!'e 'e$ $ und under er dier dierent ent vertic vertica' a' co! co!re re$$i $$ive ve $tre$$e$/ 1.("kg/ 2."kg and 3.2kg

+.0 ,e*u-t*

)eci!en @o . 1 9oading : 1.(" kg

1.(" kg  ,.+1 @  C1k@C ; 0.01( k@ 1kg

1000@

9ength : %0!! ; 0.0%!

 rea

: 0.0%!  0.0%! ; 3.%10 3.%10-3!2

5

i$'ace!ent ia' 9 =!!>=F10-4>

#roving ring ia' 9oad/ # =k@>

gauge

gauge

= 10-">

0.2 4 0.4 + 0.% 12 0.+ 1% 1.0 20 1.2 24 1.4 2+ 1.% 32 1.+ 3% 2.0 40 2.2 44 2.4 4+ 2.% "2 2.+ "% 3.0 %0 3.2 %4 )eci!en @o. 2

14 2" 34 41 44 "0 "" ", %3 %" %( %, (0 (0 (0 (0

2., ".1 %., +.4 ,.0 10.2 11.2 12.0 12., 13.3 13.( 14.1 14.3 14.3 14.3 14.3

9oading : 2." kg

)hear $tre$$

)train

=D@A!2>

= 10-%>

= 10-3> +.1 14.2 1,.2 23.3 2".0 2+.3 31.1 33.3 3".+ 3%., 3+.1 3,.2 3,.( 3,.( 3,.( 3,.(

%.( 13.3 20.0 2%.( 33.3 40.0 4%.( "3.3 %0.0 %%.( (3.3 +0.0 +%.( ,3.3 100.0 10%.(

)hear $tre$$

)train

=D@A!2>

=F 10-%>

= 10-3> 11.4 1+.1 2%.0 33., 40.3 4%.4 "2.2 "".0 "%.( "(.+ "(.+ "(.+ "(.+

%.( 13.3 20.0 2%.( 33.3 40.0 4%.( "3.3 %0.0 %%.( (3.3 +0.0 +%.(

2." kg  ,.+1 @  C1k@C ; 0.02" k@ 1kg

1000@

9ength : %0!! ; 0.0%!

 rea

: 0.0%!  0.0%! ; 3.%10 3.%10-3!2

i$'ace!ent ia' 9 =!!>=F10-4>

#roving ring ia' 9oad/ # =k@>

gauge

gauge

= 10-">

0.2 4 0.4 + 0.% 12 0.+ 1% 1.0 20 1.2 24 1.4 2+ 1.% 32 1.+ 3% 2.0 40 2.2 44 2.4 4+ 2.% "2 )eci!en @o.3

20 32 2+ %0 (1 +2 ,2 ,( 100 102 102 102 102

4.1 %." ".( 12.2 14." 1%.( 1+.+ 1,.+ 20.4 20.+ 20.+ 20.+ 20.+

6

9oading : 3.2" kg

3.2" kg  ,.+1 @  C1k@C ; 0.032 k@ 1kg

1000@

9ength : %0!! ; 0.0%!

 rea

: 0.0%!  0.0%! ; 3.%10 3.%10-3!2

i$'ace!ent ia' 9 =!!>=F10-4>

#roving ring ia' 9oad/ # =k@>

gauge

gauge

=10-">

2+ 4( %4 ++ 102 11" 121 12( 134 13" 13( 13+ 13+ 13+ 13+

".( ,.% 13.1 1(., 20.+ 23." 24.( 2"., 2(.3 2(." 2(., 2+.2 2+.2 2+.2 2+.2

0.2 0.4 0.% 0.+ 1.0 1.2 1.4 1.% 1.+ 2.0 2.2 2.4 2.% 2.+ 3.0

4 + 12 1% 20 24 2+ 32 3% 40 44 4+ "2 "% %0

)hear $tre$$

)train

=D@A!2>

=F 10-%>

= 10-3> 1".+ 2%.( 3%.4 4,.( "(.+ %".3 %+.% (1., (".+ (%.4 ((." (+.3 (+.3 (+.3 (+.3

%.( 13.3 20.0 2%.( 33.3 40.0 4%.( "3.3 %0.0 %%.( (3.3 +0.0 +%.( ,3.3 100.0

.0 S"('-e C"-cu-"tion

1. i$ i$'a 'ace ce! !ent ent ; dia' gauge  0.002 ; 0.2  0.002 ; 4  10-4 !!

2. #rovi roving ng ring ring ; dia' gauge  0.00204A1000 ; 14  0.00204A1000 ; 2.,10-" k@

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3. )hear )hear $tre $tre$$ $$ =0.2 =0.2 !! dia dia'' gauge gauge>> ; ai' gauge  0.00204A1000 0.00204A1000   rea ; 14=0.00204>A1000 k@ 0.0% !  0.0% ! ; +.110-3 k@A!2

4. )tra )train in =0. =0.2 2 !! dia dia'' gaug gauge> e> ; di$'ace!ent A tota' 'ength ; 4  10-4 !! A %0 !! ; %.(10-%

". @or! @or!a' a' )tr )tre$ e$$/ $/ = k@A k@A !!2 > a> 5or 5or 1.(" 1.("kg kg 'oad. 'oad. ; 9oad / # rea/  ; C0.01( k@CCC  0.0%!  0.0%! ; 4.( k@ k@ A !2 b> 5or 2. 2." " kg kg 'oa 'oad d ; 0.02" k@CCCCC  0.0%!  0.0%! ; %., k@ k@ A !2

c> 5or 3. 3.2" 2" kg 'oa 'oad d ; 0.032 k@CCCCCC  0.0%!  0.0%! ; +.,k@ A !2

8

%.

3.1 c! 4.4 c! Tan Tan ϕ; 3.1 A 4.4 G ; 3"H

/.0 i*cu**i i*cu**ion on

The direct $hear te$t i$ $uited to the re'ative'y raid deter!ination o the the ara!eter o  the $hear $trength o $oi'/ to ind the va'ue o cohe$ion and a'$o to ind the ang'e o riction. t the end o re$u't e had 'ot the grah/ hich i$ the grah o $hear $tre$$ ver$u$ $train. The grah i'' gained u$ to va'ue o riction ang'e. =&eer to the grah>.  t the$e 3 $a!'e$ hich are 1.("kg/ 2." kg and 3.2"kg there are no error data obtained. The va'ue obtained ro! the dia' gauge $hoed increa$e$ direct'y. Thi$ i$ becau$e the dia' gauge reading ha$ increa$ed the ti!e by the ti!e. The cohe$ion o $oi' and the ang'e o riction o $oi' are deter!ined. The ang'e o riction i$ the ang'e o the 'inear 'ine roduced ='ine8$ $'oe>. 5ro! the grah/ the cohe$ion o $oi' i$ 0.0 k@A!2 a$ the $a!'e o $oi' u$ed i$ $and. $ $ e kno that $and i$ ty tye e o coar$e grained $oi' and it i$ a$$u!e cohe$ion 'e$$. 5or! the grah/ the ang'e o riction i$ 3".The direct $hear te$t ha$ advantage$ and di$advantage$. It i$ $i!'e and a$t e$ecia''y or $and$. The ai'ure that occur$ i$ a'ong a $ing'e $urace/ hich aroi!ate$ ob$erved $'i$ or $hear tye ai'ure in natura' $oi'$

.0 Conc-u*ion

9

irect $hear te$t i$ u$eu' hen cohe$ion 'e$$ $oi'$ are to be te$ted. In thi$ te$t the ai'ure 'ane i$ orced to occur at a redeter!ined 'ocation here both nor!a' and $hear  $tre$$e$ are actingJ the $a!'e i$ 'aced in a c'o$ed $hear bo/ ied at the ba$e ith the to ree to tran$'ate under a horionta' orce. The to ortion$ o the bo are $aced by u$ing $acing $cre$ to reduce the riction. The $ace $hou'd be at 'ea$t a$ 'arge a$ the 'arge$t $and artic'e. The bo i$ then 'aced in the direct $hear aaratu$/ and increa$ing horion horionta' ta' 'oa 'oad d i$ a a'ie 'ied d ith ith con con$ta $tant nt corre$ corre$on ondin ding g vertic vertica' a' 'oa 'oad/ d/ and the horion horionta' ta' deor!ation $ha'' be recorded by u$ing the dia' gage. 5or each te$t $hear $tre$$-$train diagra! diagra! i$ dran in order to ind out the u'ti!ate u'ti!ate $tre$$/ then the $hear ai'ure ai'ure enve'oe i$ dran by re'ating each u'ti!ate $hear $tre$$ to the nor!a' $tre$$ corre$onding to it in at 'ea$t three te$t$. The direct $hear te$t can be u$ed to !ea$ure the eective $tre$$ ara!eter$ o  any tye o $oi' a$ 'ong a$ the ore re$$ure induced by the nor!a' orce and the $hear  orce can di$$iate ith ti!e. 5or the eeri!ent e u$e the c'ean $and$ a$ a $a!'e/ $o there i$ no rob'e! a$ the ore re$$ure di$$iate$ readi'y. Koever/ in the ca$e o high'y 'a$tic c'ay$/ it i$ !ere'y nece$$ary to have a $uitab'e $train rate $o that the ore re$$ure can di$$iate ith ti!e. irect $hear te$t$ can be eror!ed under $evera' condition$. The $a!'e i$ nor!a''y $aturated beore the te$t i$ run. The te$t can be run at the in-$itu !oi$ture content. Beore e ind the va'ue o cohe$ion and riction ang'e/ e !u$t 'ot the grah ro! the data that e get ro! the eeri!ent. The re$u't$ o the te$t$ on each $eci!en are 'otted on a grah ith the eak =or re$idua'> $tre$$ on the -ai$ and the conining $tre$$ on the y-ai$. The y-intercet y-intercet o the curve hich it$ the te$t re$u't$ re$u't$ i$ the cohe$ion/ cohe$ion/ and the $'oe o the 'ine or curve i$ the riction ang'e.

10.0 ,EFE,ENCE

•

Braja Braja . a$/ a$/ #rinci #rinci'e 'e$ $ o ?eo ?eotec techni hnica' ca' Eng Engnee neerin ring. g. )e )even venth th Editio Edition. n. )I Editio Edition. n. *engage 9earning. 10

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