Question 1: A 9.61-cni3 sainple of soil vteighs 19 g. After being dried in an oven1 its

\veight :i.s 17.5 g. If 0, = 2.67~ find: /VL =- 1\j :'.:" (j_ ()/Ct /c.cJ .'. t,J: 0. DIC,~ ,JI

- \~ 3 \j =: °i . b l t = 0 , b I ( I D :i /\,\

a) Starting unit weight~ Ym s -= 17. s:",.<.) ::- o, o I "? ;-· l'-S . '. lJ5 = o. I 7 7-. ,j

_ O.c,1q ~9 ·-=·,._..,--.~-- .·

9, 6 / D rl!j lA ,..>

h) D1y unit ,veight. ya

l-J5 i\)\.~··==-~i T_, - V

c) Water content .. tc

LJ :::- __ (IO"--"')::=

LJ>

lt)t.,J =- lJ-

d) 'Void ratio. e

lZ- E"M.tJ'-1 1~ ;;;-R-,., /f ,j.._

e) Porosity. n

f") Degree of &aturatiorE S

0 , 0 / ~-··-»1..J ( \

0 ,( 7L ;_s-

C,<, o, oJrb - ~ e-- 6.L/k,

e., ~- o. l) b

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t. A11 1111di:--tJ1rfa'<l• Sfll11J)fo of ch.w has. g• \yet 111.ass of lt)O. kg, ·'1 .dry.n)t'i$SOftla kg1 .. and .• ,l.tot,H. volurneof tl04Hl ni. Th€ :sQlids have a specific grnvity of 2.65. Tht:' ynidratio iB•most..uearly

(A) tl.31

(B) 0.40 (C1 0,61

(D} LO

w

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2. A. sa tur<tte.d sa11tple. of undisturbed clay hflS a wet ma.~ i5r3l8 kg and a dry lhf:\Ss of 204 kg. The total Yolume of the san1ple is 0,19.3 m3• Most nearly, what is the specific gravity of the soil sdlids? ·

(A) 2.4

(B} 2Ji

(C) 2.7

(D) 2.9

\/\l -

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3. A soil's grain-size distribution curve is as shown. The effective grain size is 0.19 rnm, and D60 'is OA9 mm.

100

""'\ 80 I ' ..

• ' .,

: 1,

'

~ 20

'' \ •

a...__

10 1 OJ O.Q1 grain size (mm)

The coefficient of gtadation is rllost nearly

(A) 0,17

(B) 0.44

(C) 1.6 .(:­

(D) 3.0

0,001

I, 1

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4. A soil has the following characteristics.

percentage fines, F 69% liquid limit 72

Ftl..0 ;.A viJ I r.:::1f!F'e:::;,, CL-ll.55 1,:::::-1cA Tio~ Utfl'l.-.-1

a:

plastic limit 48

Using the Unified Soil Classification System, what is the classification of the soil?

(A) GW

(B) ML

(C) MH

(D) CH

Far classifie2'J111111, ctfi·!le---::,raaried :wrls and m,;.g-sine,:1 tract1arc ·Cif .:,:,a:;:~iae<I

Eqaatiar, of ·~.'-iil'le

x 41J Hc.~,rJ~ Et Pi =-4 to LL = 25. 5,, !tier. Pl:="· ?3 [ll-'20J

w a z ~ 30 [5, ' r;::Z'/ (I) 2() :s (L

10

EqillWan of "U"-une VMica: at LL= , 6 ID P!( = 7, men P:\=M (LL-!l} ~-+,,--1--__,,..__--+----+--+---!--

71-~~ ;IJ"':t:r.+ 'J"'J.,,. ""., fr'if'lrr"':..,..,..__ "v",r 4 o~~-~-~-~-~-~--'--+--'---~~-~ o rn 16 20 ::io 40 so 60 10 a:o so rno ·110

~~ 7~ ~ sample of soil has the following characteristics.

6 a% { '~ 7

'F7A,Jc

LL ~ 72- > ~ s,cr-~

P:t- PLDI>

. , M H

% passing no. 40 screen 95 \-"I =-LL -'PL ::, 3 I - I l5 % passing no. 200 screen 57 liquid limit 37 F =- ~ ~ plastic limit 18

What is the AASHTO group index number?

s-oi<.

(A) 5 ~,:r:· = ( F --.;; s )[ O, :2.,, + 0, oc::,~(LL-'-l o)j--\- o. o \ (_ (B) 6

-1s-)[PI-IOJ

(C) 7

(D) 8

2. z.( (),/ $,r

GENERAL CLASSIFICATION GRANULAR MATERIALS ( 35% OR LESS PASSING oms SIEVE)

A-1 A-2 GROUP CLASSIFICATION A-3

A-1-a A-1-b A-2-4 A-2-5 A-2-6 A-2-7

SIEVE ANALYSIS, PERCENT PASSING: 2.00 mm (No. 10) s 50 - - - - - -

0.425 mm (No. 40) - s 30 s 50 ~ 51 - - - -

0.075 mm (No 200)- s 15 s 25 s rn s 35 s: 35 s: 35 S:35

CHARACTERISTICS OF FRACTION PASSING OA25 SIEVE (No. 40):

LIQUID LIMIT - - s 40 2 41 s 40 2 41 PLASTICITY INDEX* 6 max NP s 10 s: 10 ~ 11 ~ 11

USUAL TYPES OF CONSTITUENT MATERIALS STONE FRAGM'TS, FlNE SIL TY OR CLAYEY GRAVH AND SAND

GRAVEL. SAND SAND GENERAL RATINGASASUBGRADE EXCELLENT TO GOOD

SILT-GlAY 11/IATERIALS I MORE THAN 35% PASSING 0Jl75 SIEVE l

A-7-5 A-4 A-5 A--6 A-7-6

- - - -

- - - -

~36 ~36 2! 36 ~36

s 40 2 41 s 40 ~ 41 s 10 s 10 ~ 11 ~ 11

Sill'!' SOILS CLAYEY SOILS

FAIR TO POOR

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9. The ~P(>\~ifk gTaYity of the soil solids in a given .~lmJ)it0 is :3.11. The pon,sity of the soil is 27%. Wliat is n1ust rwatly the (•ffcctive unit weight of the soil sarnple?

,A 1 96 lh(:ft:3

: Bl 1.1 O lbf/ ft:'

,Cr 1:)n 1bf/ft3

,.D mo lbf;fta

I +t:_.

I+~

U\ = 27

• I I

( -;g ' I I + ('.):~ ? ) ,~ z . '-I I + o, :?, ?

10. The total unit weight of a given sojl is 120 1bf/ft3 •

Th1;:' ~1U has a porosity of 0.26 and is 100% saturated. Ti11;, dry unit w:ight of the soil is most neaty

GS lbf/ft3 t ~ I ~ Y:r !B) 8-0 lbf/ft3 -.111.-, , t

tC) 100 lhf /ft3 V\ :::: o, 2. b

(D) 120 Jbf/ft3 \J IJ = \)l,J

\j

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11. A l L field sample contains .soil with an initial wf·ig;:ht of 30 N. The soil is dried completely in ari ove11 at 100:c. The weight of the soil after drying is 22 N. The m;i;.xitnu.tn volume of the dry soil sample is 1.5 L, ,HJd th<: minimum volurne is 0.60 L. The relative density of the soil j:,, rnost hearly

0 I'> - ~-1:, iJ\IJ\. -------6,;;.MA;- ~P"II"-

(A) ;J7'){

(B) &t/;{;

{C) fj2(J1,

(D) 75¼

w .:- >CY~

\J = I L. ::; ~: C;;'. ( l(' I ~ ( f,\ I VI.)

12. An undisturlx~d 10 crn wide x 10 cm Jong x 5 crn high sample of d::Jy has a dry weight ofa2 kg. The dried soil sample is co1npw:t<J<l into a n,inhnnm w1hune, a rectangular prism 8.5 .crn wi<fo >< 5) cm high x 3,5 crn high. What is most nearly U1(i telt.1.tive compi1,ction of the soil sample?

'\., ~\-

'l l ,J,

('.)_ b \_

(A) 33%

(B) 45%

(C) 49%

(D) 54%

:,. = S"eiO t:_M

~2 k..s ~_,_,_._.·--- - --

:;t

~DOC~

!~:...~,'.: p ... C i I,;) o)

t 'f>' /J\J.. y

C), 0 b'---)

I /ll\Af)

o,

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-

\1 if'lA Boil sample has the particle size distribution ::;)1own.

100

/ i-- ,--

90 I/

80 I

I 0> 70 C V ·- ,,....,.. en t-'v co /i.--

~I-'-

;:- 50

/ C

~ 40 ... J (I)

n. 30 V

20 j

I 4'\

L----" '

0 1 \,IS" 10 0.1

0, 2.-1 particle diameter (mm}

What is most nearly the coefficient of tmiformity of the soil?

(A) 0.4

(B) 0,8

(C) 3 (D) 6

D~o

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14. A soil has ·it void ratio of OAL The unit weight of the solids is 33 kN/m3. ·what is most nearly the sat­urated unit weight of the soil?

(A) 26 kN/m3

(B) 29 kN / m3

(C) 33 kN/m3

(D) 37kN/m3

i~~, I~ ( G~ t- e-) 6~ \+e_

1 s. The water content of a saturated soil sample is 26%, and the void ratiois 0.57. The unit weight of the solids is most nearly

( A) 4.5 kN/m3

(B} 9.8 kN/m3

(C) 22 kN/m3

(D) 28 kN/m3

1':, :::--l,...JJ, ---\Is

cJ<-,J e_ = C.0

"' ~~,;=,~ -\111

v

I ,J L-,1 W ---A---•-

/ +-- O,L/1

b

\j ,f -) ~ "1v :::::c ---- -

\j '.,, - --~ e--

e_ Yw {..,) e-I ---- ::::

~J tJ ·W

( e,1, ~7)[ q, <i5f ~) ;::- 2.- I, C C>. ~ 6

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16. An undisturbed soilsample with a volunie of0.30 ft3

is weighed in a. 0.2 lbf pan. The combitied weight of the soil stunple and the pan is 40.5 lbf. The soil is then completely dried in an oven at 100,;,G, After drying1

the combined weight of the soil and the pan is 35.2 lbf. Tho unit weight of the soil solkls is 194 lbf/ft3• \\That" is rnost nearly the volume of the air-in the original soil sample'? s:: ,l,..A-'\" '--c

(A) 0.010 ft'1 \} :.- D, 3 ~:::,

(B) 0.035 ft3 L.,_j . ~· CJ , '1.-.. l 6 ( p .~ ,.j J ir

(0) 0.10 ft3 {JJ + W\? -=: L\ 0. S°'- \ \:J (D) 0.21 ft3

W = y b. ~ )b - 0, 'L~.· lh <e; t1 o,

W1.v + -jr - - J},. >. ':,, l ;a,

)et'

\ i - w,,., ~ .r-\1 J - ~ ---

_\ (,, l, ti

~!J ~ 0,00 ~ d'*?

\)

I b - v'-'r = 3 s I la

lb \Ci'-\~

\} 1' ~ lJ.:, - _ ~-I~ =- o. 1 t I~ l( f;,

,..'\-

//11/ A OJO n?. ~ltnrnt:ni Sl_)i! s:nnplc is \\'(>ightcl in R :14 kg ~;111. 1 'h(' ('( )lH bu I('(~ \\"('lght ot tl1<' soil n,nd t be J)1'H 18 4t1() kg.

Th<' :st)il s;nnple JB corn.plctdy dth'd in a11 nn•n. Afl(\r dr>·ing. i he crnn!>ilH':I wdght of th(' soH !-,nJnpfo nnd the p,rn i~ ~18S k~. \\ hnt 1~ 1llo~l tWnrly th(' \\nit weight of tlw s.;~turnt('d ~nil i-a mpl<';

p) :27 kX,'1n:1 lUp = "3> t( l....:J (T3l 31 kX 'in'J

l C) .n k:\' m:, k . J

1 D) ,Jl · ·\ 1n··

q I h .-: '3-S-I t Ld\J

w,;J =- b s:-- le:,

0 =- 0,\ ~3

F = !{ e,,_ :::- l0 &,,. ::-- t~( I 1~ h:..~

=LI, OB (<-~

1

0)5= -~ \} ~ (,)

\ IJ I + /, f:: r7

,,·•r•s·-,-,> ,,- ,..,_~,o~e~-,c;~~ ' C

y<;-i,~ y V. Y-- > .("',.

D ,;'--

tt ~-. l,) ll' G2J Lrl =-res ---;~-i 1,1 o. k~-~-~ ~

{'A 'J.

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18. T1w n'sult:- of a sieve analysis are sho,v11.

i•} l ~ I

so'. I l SJ..1' "',

g'70' ·;; ..... ..,: ... ...., ..... !

; 50; ~ 40 1 " ' ~ i .c.. .......... ,

201 .~1

v! ol 0.01

l I

V

I

V I

----11 0.1 I '" 1

. O,L) O,Jr' rn particle diameter 1mm)

-----

10

\Jost nearly. ,vhat is the coefficient .of curvature of the soil sample?

fAJ 0.3

(BJ Q.7

IC) 2

{D) :1

0.bo~ c;,,7

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D

For a fiow net shown in the following figure, determine head loss at points A, B, and C. The structure is approximately 100 feet long. Determine the flow rate in ft3/min through the permeable layer. Assume hydraulic conductivity, k = 1.64x 10-4 ft/min.

20ft.

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Fl ,J ~ ,H---c,' ct+A....J<:;~ I ,J -JO ( 'D ~,·1 t, { r::::,.,) A-Ff5 \(_.-LA'( c\L... eJ F .SA .J l> Fl L- L

t.S PLA-LGD

1'-lORJ\J.-L.( Co,-...}<;:.OL( t::,>A""fS-t"'::, c LA'j L~)""c\t.._ c~-'-, C.L.A.Y) ?'0 ILi,

L1 Q\)l D L\MIT (LL)= l.\ c;:-

CL---::: C'), 00°1 ( L \_-\,0) P5 14? -CL ~ C). 0 C) 9 ( \..\ S- I V) ::::::- 0 . 3 I '::>

~('.) \LMJ..-Lj Cot-:l S: 6\...., p.r.. ,c::D

CLA-y

? LA:- c_c:- <;p,.,._\ ~ :p-, L l- C) c--J >'-.l\2.-.~ Ac_C, \J'E''L"\\C.A\_ S""\\L~'.:::,..>r.rJc..,~.:A$ GP ai-~~~f),.::

ffoLJ /VltlC..rf (..,UILL- T-HE \}Dt,:> 12ATID. (c·) '.~ · i>Or,-..J-r- (> . pc::-G~AS~,, I

C1.JG ,..,.-o rt/€ ~,?:G:,;,,.!::. 1.AJc.-l2-eA:-S> e.-.? ~ ~ ?_De,~

-~' = '?'L:>0

I ) 1 a;-~ CY;'+ c:r,- = Z-- ~Ou ---­~-e--J

o, I 7 /

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( s ss-rtMA-, so -r1-14, 1 ;-1-E -rorAL-- S:EcTTLe.M'<=-i"JT""( Sc..),~ ,z_/1

co.,,'F, "-•-~ cYF CD('..J S::Du p/C,l oJ (_ ~) \ S 0, OS ~ Tl'M. b \L c Q U \ \L€[::;> Fo1L- .s;-o t: Co.,j,~DL l DA-Tl o ~PV

rlf+::;;., -ro ,-A L- c:;,.-:G-r,-L --e- MC;-'--,- TD oc_e_ J t2.. I f;. ?

S :::-- L 11 c_

so

b

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i

t -

Ll-1-- -I "--

<;u t:>~ ....\ ~~}'.\,-J ~ (;.e ~ \>A,tf '13LC::C...1~0

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A Lt::>AC OF 2.oo )i \,S ?L.A-C..C:::-1:> 0~ A -g,1~(\ 3,0- \~t:v('.

F' ,.J t::::> s ~-cA_~ ~->> .µ:;r:-· FP..1 L tJz_;;: •

C) IV C ,.J '.

A=- --s,11. '(31";:: °t 1v\ .,_

F ;:=- '°2-DD \b

I'

H- ~I{)

__;Tr7 i?v ii .· I l / _, /1 ./ I .

/ I/

i ;I:; I / I, r (

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' . i

\

--r,,..,,,---0---+-----.._____\ \:? = l~ 6 H

c> _ r LI -,-- I 2 o (_-, (j t ! - -

\ )

(• !

7

-S.p,.,tJ I> 0~1'2.__0fc..';:;-(p ::;c 3 J- ~

CA.Lc___'-'LA1E -rH-c ch./tz .. :T~J'2.,J,.,._j C;, (V'lo0G.0T [)0-t? TD T7+-c

A-c__,,Jt:= -S:-Ae..-TH f~£?...5 ucz.2:·"

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_1. A soi1ha~anan:gleofinternalfricticinof25°. What is nh"~~ . rn',~;·ly tlit~ JfonkiiW acti,·e earth pressure Cf>t'th\'lt'U t ;

t.\1 o.:n 1rn 0.-11 ·.

C) 0.52

\D) 0.58

Cf> :::- z. s_;-¾

r-A ~- rA 0·7-.c· c, - f:'j --- o , </ 6 ,;:,

2.' A soil has an angle of internal friction of 25°. \Vb.at is mc,st nearly the Rankine passive earth · PNSsure cocfficien t?

(A} 0.59

(B) 1.()

CC) 2.5

(D) 4.1

3. A retaining :s.vall supports soil with a vertical height rjf 2 111. The soil ha-s an angle of internal friction of 32° and a specific (unit) wejght of 25kN/ni3. l\fost heady, v;,·hat is the active lateral soil resultant?

(A) 5.0 kN/m !BJ 15 kN/m

(C) 46 kN/m

W} 92 kN/m

/c~ I

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176~,~~t--1~ UL-1! MAT~ Ot--:P..'2-~lAJ~ LA.i(.Ac.C.. 1\/ f-0 ft--

ro 0,1A.J c...,

GJvZ~.'

D!--==- s t~ y l ~ \ -i s- [0l'3

c_ ::: \ 1- D~ 1,L 1-

~o(L--- C)r <;.../:..."F"e:--i-7 -==- -:::?:

~=o

~J--=- ~, I '-j tJ\-:;: \ f'--J 't:::: b

_ ( \ '-- " 00 _[!,_ ( c;:, I 'I) -r ( n J;.- £;) ( 3 J,,)( " }t

- ?If;/

D

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\ er = cs--- - LA.

'\/ l \ UL-= 0...__j • d

0 D

\ ' ) ~) (q_ - I I I.._-,

A

/

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2 ft

8 ft

Surcharge= 1000 lb/ft2

Sand 'Ysat=llO lb/ft3

~ ::: r . H =- , i o ll c 11 ( , = t1 l) o 1!~ ~ ~~ ~) ~~

Normally consolidated clay

t .r+

Ysat=llO lb/ft3 \"l, ~;: t,,J~,l~ f? ;:-;, V IL~@._ L-

t-\ ::- 6 l' ,; {~~ ( z ~ + ll h) U-- =- ~ ·-u .:=- :J '7Y ,L\ lk-.

Sand

Calculate initial effective stress at center of clay layer clay layer before application of load

Effective stress at center of clay layer after

application of load:

/b --L. z_. :;;:-',c,

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6) An excavation is made in uniform soil. The available shearing resistance along an assumed slip surface is 1350 kN/m. The mobilized shear force along the slip surface is 46.5 kN /m. The slip surface makes an angle of 45 ° with respect to the horizontal What is most nearly the factor of safety against slope instability?

(A) 1.5

(B) 2.1

(C) 2.9

(D) 4.l

-/FF' --r::; =-

<7\ :::- l\

rs.

1--:::- :;-o k,JJ ---t''-

'-I &S:- k.,;-.J -IA--

_,'.)) s

- I~ ---r::·~J:.)

G~) A retaining wall extends 3 m from the top of bedrock to the ground surface. The soil is cohesionless and has the properties shown.

/ retaining wall

f ground surface

H=3m

4> = 35° p = 1834 kg/m3

Using Rankine theory, the total active earth pressure per unit width of retaining wall is most ne11rly

(A) 15 kN/m

(B) 22 kN/m

(C) 44 kN/m

(D) 82 kN/m

0. t. t(

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1 4, An excavated slope in uniforrn soil is shown .. The SfJ1,cifk weight is 14 kN /rn\ the cohesion is 15 kPa,

j If .. ··11".0 aw the angle ofinterna nct10n IS . 0 ·

What is most m;f1rly t}w avaihthle 1,heasing resisti:mce along the assmrw,l foJh1re plauc?

(A) 550 kN/rn

(BJ 600 kN / rn

(C) 680 kN/in

(D) 940 kN/tn

L,d1,,_ :~ i [ (11:,)(__ LO)+-± (1),3)(1u) -1Jg7,"3)( lo~

:: 1),:,,./

' 5~ 'A uniform soil slope has a pla.nar slip surface le.rtgth of 100 m. The soil's cohesion is 5 kPa, and the angle of internal friction is 40°. The angle that the assurned fail­ure pla11e 1nakes with respect 'to the horizontal is 25'°. The weight, of the soil mound above the assumed failure plane is 2000 kN/m. What is most neatly the rnobilized shear force a.long the assumed fail me plane?

(A) 500 kN / rn

(B) 850 kN/rn

(C) 1500 kN/tn

(D) 2000 kN/m

X1 -:~. = 11."3""­-rA~'!.o

)l. L ,,,.. L ~ Y--1 = 'J I' 5- LJ - \ f ''), ::, 2.. 0 ii'--

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Find the factor of safety for the-- instable slope. • C=500 psf • Y = 120 pd • c1-- = 15 degrees • ~ ,cc 30 degrees • theda = 26.6 degrees

c._O Y,_:::: --· :::- 3'l. 6

I Th~~ I --77'-------------· ··- + --

I

\-\ = Lb

I y ____ ., ________ , _____ ,_,._,,. ----, ...... ,, ... = l!0-1 -t l, - , b

?

('.l C CJ(. OSI\ cJ-= 2-0 -· !;.\ 63

L-~ :::77. L

~ /.lt)D S, ./1 \ - I l. L/ )

'C:' w s;. /•I\ -· - ~. ,M,oD

6 6 Se,,

S. - ~ -·

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A 25" high slo~ i:s dm,igm.,-d ,m pmi uf a highway prqjcct .llii\ sho,;,.vn belmv. Ass1uning a \Vm:igc type foilnre occu:rs~ oolculnte the f aclor of safoty_

,,L---- ------- f Vt~ 128 pc.· <()=32° C (undrained shear strength)= 65 psf

\_,,-} ____,,,,.,-- 1

~ __,

IL~ L I '----

( XL) z_ 5- -,1- -J: (_'II) ( "LS-) - l . L s-) \;_J,, _ I '1 ',; \_'( ,-s-\( lS ') + j: (so)( ~1-J - j ( 7 s-)(2 ,,--~ ~ ([ D, ,mo

S1 V • I - I z l '>- z..

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