baghdad subgrade resilient modulus and liquefaction evaluation for pavement design using load cyclic...

8/13/2019 Baghdad Subgrade Resilient Modulus and Liquefaction Evaluation for Pavement Design Using Load Cyclic Triaxial

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Journal of Environment and Earth Science www.iiste.org ISSN 2224-3216 !a"er# ISSN 222$-%&4' (nline#)ol. 3* No.12* 2%13

12$

Baghdad Subgrade Resilient Modulus and liquefaction Evaluationfor Pavement Design using Load Cyclic Tria ial Strength

+r.Saad ,.I rahim.Sc.* /.Sc.* !h+ 0.E.#./ISS/ E./.I. S0E* 0ollege of Engineering.* l-/ustansiria niversit * aghdad*

Ira5.Email drsaadfarhan7 ahoo.com

!bstract!avements fail for different reasons8 "oor design* "oor materials and "oor construction methods are the mostcommon. 9he "avement foundation su grade# re"resents one of the :e elements in the "avement design. 9he

merican ssociation of State ;ighwa and 9rans"ortation officials S;9(# "u lished the S;9( uidefor +esign of !avement Structures S;9(* 1&'6# in which the use of


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su Bected to re"eated traffic loading* can occur through two "rimar mechanisms - colla"se of the "avementstructure or crac:ing of the surface of the "avement. colla"se of the "avement structure can occur due to large

"lastic "ermanent# deformations in the su grade soils. ;owever* even when the loads on the "avement are note=cessive ut nominal* the "avement surface can crac: due to fatigue* caused the reversal of elastic strains at

an location in the "avement s stem. s a result of re"eated loads such as those caused moving traffic*cohesive soils in the su grade incur re"eated elastic deformations. Dhen these deformations e=ceed a thresholdvalue* "remature fatigue failure of the fle=i le "avement through crac:ing of the "avement surface occurs.

>im 2%%4 studied the suita ilit of e=isting regression models and* if necessar * develo"s an im"rovedmodel for "redicting / r of cohesive soils without conducting e="ensive and time-consuming / r tests. dditionaltests were "erformed on sam"les com"acted to o"timum conditions ut allowed to full saturate. / r "redictedfrom si= e=isting models studied showed wide scatter and "oor correlation with the measured / r . n im"rovedconstitutive model was develo"ed to account for the effects on / r of the stress state of the soil and itsengineering "ro"erties o tained from sim"le la orator tests.

eorge 2%%4 used an e=isting models to stud significantl overestimated the / r of a cohesive soil* the "ro"osed model "redictions are close to the e="erimental values and are in most cases a slight underestimation.9his im"lies that / r )alues "redicted the "ro"osed model are generall slightl conservative* and can esafel used in the design of fle=i le "avements to e uilt on cohesive soils. 9he "ro"osed model can e a usefuland relia le tool for estimating / r of cohesive su grade soils using asic soil "ro"erties and the stress state ofthe soil.


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stress* deviator stress* and num er of loading c cles. fter the 1&'6 ado"tion of / r of soil for the design of "avement structures* the severe sam"le conditioning efore testing often resulted in distur ance to the soilsam"le* and sometimes sam"le failure was e="erienced during testing. In 1&&1* S;9( 92&2-&1 modified92?4-'2. 9he se5uence of a""l ing the confining "ressure and deviator stress to the s"ecimens in the S;9(

92&2-&1 testing "rocedure has raised some concerns. s shown in 9a le 1* the S;9( 92?4-'2 and 92&2-&1testing "rocedures allow various waveform and loading fre5uencies* "ermitting the tester to choose among thevarious o"tions. 9his ma lead to different / r )alues for the same s"ecimen. In 1&&4* S;9( introduced92&4-&4 ased u"on the S;

S;9( 92&4-&4 testing "rocedure ields more consistent results than the other two testing "rocedures 0laros*et al. 1&&%#* and 0osentino* et al. 1&&1##. /ohammad* et al. 1&&4# re"orted that the S;9( 92&4-&4 testing

"rocedure ields higher / r than those o tained using the S;9( 92&2-&1 testing "rocedure.s shown in 9a le 1* the S;9( 92?4-'2 and 92&2-&1 testing "rocedures allow various

waveform and loading fre5uencies. !ermitting the tester to choose among the various o"tions ma lead todifferent results for the same s"ecimen. In 1&&2* S;9( introduced 92&4-&2. 9his "rocedure is asedu"on the S;

"rocedure for measurement of / r in 1&&4* and designated this testing "rocedure as S;9( 92&4-&4. Ithas een re"orted that the S;9( 92&4-&4 testing "rocedure ields more consistent results than the othertwo testing "rocedures 0laros* et al.* 1&&%8 0osentino* et al.* 1&&1#. /ohammad* et al. 1&&4# has re"ortedthat the S;9( 92&4-&4 testing "rocedure ields higher / r )alues than those o tained using the

S;9( 92&2-&1 testing "rocedure.

9a le 1 0om"arison of resilient modulus test "rocedures after >im2%%4#

Testing

Procedure

+aveTy)e

Load

Duratio

n,Sec&-

Cyclic

Duratio

n,Sec&-

. d ,/Pa- . * ,/Pa-

0umberof

Cycles

92?4-'2

Sine*

;aversine*


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9a le 2 0om"arison of !46 and 93%? after roeger et al* 2%%3#Protocol s)ecification P12 T*34

9 "e of @oading S stem ; draulic ; draulicH!neumatic

@oad control

uses 2%% "oints and not $%% as in !46*and its c cle can have duration of u" to 3

seconds8 in addition* :neadingcom"action can also e use as an

alternative com"action method. 0losed@oo"

0losed @oo"

@oad 0ell @ocation E=ternal E=ternal+eformation /easurement E=ternal E=ternal

0onfining ,luid ir ir@oad !ulse Sha"e ;aversine ;aversine

@oad duration %.1 s %.1 s0 cle +uration 1.% s 1.% s to 3.% s

Num er of @)+9s 2 2K of "ts "er c cle $%% 2%%

S"ecimen @H+ neading

1& Parameters !ffecting Resilient Modulus of 5ine 6rained Soils/ r is numericall e5ual to the ratio of the deviator stress to the resilient or recovera le strain after large

num er of load c cles / r Ld H Mr . 9he resilient modulus value can e estimated directl from la orator testing*indirectl through correlations with other la orator Hfield tests* or ac: calculated from deflection measurementsthe resilient res"onse of a soil has een studied and documented several researchers over the "ast $% ears.9hese studies evaluated the characteristics of / r for cohesive soils in association with the stress state andengineering "ro"erties* and develo"ed "rocedures for estimating / r . 9he results of these studies show that / r ofcohesive soils de"ends on deviator stress* confining stress* water content* and degree of saturation* "lasticitinde=* unconfined com"ressive strength* freeCe-thaw action* and "ore water "ressure.

/ r of cohesive soils at constant confining stress decreased nonlinearl with increasing deviator stressSeed* et al. 1&62#* ,redlund* et al. 1&??#* Doolstrum 1&&%#* +rumm* et al. 1&&%#* @i and Selig 1&&4#* !eCo

and ;udson 1&&4#* @ee et al. 1&&$#* /ohammad* et al. 1&&* >im 1&&* ;uang 2%%1#* and /asada andSargand 2%%2##. /r for cohesive soils stee"l decreases with an increase in the am"litude of the c clic load u"to a deviator stress* called the rea:"ointA suggested 9homson and im 1&. >im 1&&* and utalia* et al. 2%%3# showed that the effect ofeffective confining stress on / r of cohesive soils graduall decreases with an increase in the moisture content.;owever* other researchers have suggested that the confining stress around cohesive soils has no significanteffect on the / r ,redlund* et al. 1&??#* /uhanna* et al. 1&&* and /asada and Sargand 2%%2##. 9he effect ofthe num er of re"eated stresses Seed* et al. 1&62# and


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9a le 3 Summar of E=isting / r im 2%%4#E isting Model 'n)ut Parameters !dvantages Limitations

S+ /odel0armichael Q Stuart*

1&'6#

S0S soil t "e* !I* w* P "assing No.2%% sieve* R3* Rd

Includes effect of- R3 - !I- w

- @inear model- Soil t "e

; "er olic /odel+rumm* et al.* 1&&%#

5u* P of clay * !I** S* P "assing No.2%% sieve* ; "er olic "arametera*

@@* Rd

- Nonlinear modelIncludes effect of

- 5u- !I- S

- R3 not considered

+(9 /odelSantha* 1&&4#

w, w opt *d*d*ma=* P of silt* P ofcla *P swell*

P "assing K4% sieve* S* P shrin:age*@@* !I* Rd* !a

- Nonlinear modelIncludes effect of

- w and wopt- S and !I

- ! a

- R3 not considered - 0om"le= model

- /an tests re5uired

9+(9 /odel!eCo Q ;udson* 1&&4# w, d*d*ma=* !I* Sam"le age* R3*Rd

Includes effect of- w- !I

- Sam"le age- R3

- @inear model- In"ut "arameters have

narrow range

0S /odel@ee* et al.* 1&&$# Su at 1.%P of a=ial strain* R3*Rd

- Nonlinear model- Sim"licit of /odel

- R3 at %* 2%.?* 41.4 :!a- 13 :!a R d 6% :!a

(+(9 /odel(+(9* 1&&

I P "assing No. 2%% sieve* @@* !I#*0 < - Sim"licit of model

- @inear model- R3 and R d not considered

(S /odel 2%%65u* P of clay * !I** S* P "assing No.2%% sieve* ; "er olic "arametera*@@* Rd * w, d*d*ma=* !I* Sam"le age

Includes effect of- R3 - !I- w

- @inear model- R3 and R d t considered

7& Sam)le Collection aCalia >1# and l./ansour /1#.

@a orator tests were "erformed on the sam"les to determine their asic engineering "ro"erties. / r andli5uefaction 9ests were conducted on soil sam"les at three different moisture contents which are dr ofo"timum +(!#* o"timum (!9#* and wet of o"timum D(!#.

2& Basic Engineering Pro)erties of 8sed Soil@a orator tests were conducted on the four soil sam"les to determine their asic engineering "ro"erties.

@a orator tests conducted were tter erg limits* sieve anal sis* h drometer* Standard !roctor com"action*unconfined com"ressive strength* and tests. ll soil sam"les collected were trans"orted to the Soil/echanics @a orator at 9he (hio State niversit As +e"artment of 0ivil* Environmental and eodeticEngineering. 9he sam"les were oven-dried at 6% 0* for 24 hours and then air-dried in the la orator over a two-wee: "eriod. ll dried soil sam"les were thoroughl "ulveriCed.

ccording to nified Soil 0lassification s stem in S9/ +24'?-&3 and S;9( Soil 0lassifications stem in S;9( /14$-&1* the soil t "e for each soil sam"le was identified on the asis of the results of

tter erg limit* and "article siCe distri ution tests see 9a le 4#. In the nified Soil 0lassification s stem* asshown in ta le 4 were found to e classified as 0@ low "lasticit cla # for 1* O1* /1 and :1.tter erg limit tests were "erformed in accordance with S;9( 9'&-&6* and 9&%-&6 testing

"rocedures. s shown in 9a le 4* the li5uid limit of -6 location ranged a out 3'* and that of -?-$ locationswere much higher 4% to 4. 9he "lasticit inde= of -6 grou" ranged a out 1? while it shows higher for -?-$which was a ove 2%.

Sieve anal ses and h drometer tests were conducted in accordance with S;9( 9''-&?. s shownin 9a le 4* all soil of -?-$ had a""ro=imatel highest "ercent of 0la generall ranging from 4%P to $%P#.9he -6 soil had 0la ranging etween 2$P and 3%P. 9he -?-$ soil had the lowest amount of sand.


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9a le 4 0lassification and Engineering !ro"erties of each location

Standard !roctor com"action tests were conducted on each soil sam"le in accordance with "rocedure in S;9( 9&&-&? testing methods as shown in figure 1. 9a le 4 summariCes the o"timum moisture content*ma=imum dr densit * sam"le moisture content* sam"le dr densit * and unconfined com"ressive strength forthe soil sam"les for each location.

nconfined com"ressive strength tests were conducted immediatel after sam"le com"action in accordance withS;9( 92%'-&6 testing "rocedures. 9he unconfined com"ressive strength tests were conducted on each soil

sam"le at three different moisture contents. s shown in 9a le $* the three different moisture contents were drof o"timum moisture content +(!#* o"timum moisture content (!9#* and wet of o"timum moisture content

D(!#.s shown in 9a le $* the unconfined com"ressive strength for -?-$ grou" were found to higher at dr of

o"timum moisture content* than values o tained from (!9 and D(!.In general* the dr of o"timum sam"lese=hi ited the highest unconfined com"ressive strength values. 9he measured strength values t "icall decreasedwith increasing sam"le moisture content.

9a le $0om"action and nconfined 0om"ressive Strength 9est


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131

4& Evaluation of Resilient Modulus ,Testing Procedure-9he maBor com"onents of / r testing as "erformed in the Soil /echanics @a orator at 9he (hio State

niversit are shown in ,igure 2. 9he s"ecified load was a""lied a loading s stem manufactured /9S.9he 9ria=ial "ressure cham er see ,igure 3# was modified to include a load cell to measure a=ial load* an

@)+9 to measure a=ial dis"lacement. 9he @)+9 was mounted on the e=ternal steel rod in the to" cover of the9ria=ial "ressure cham er.

,igure 2 / r 9esting S stem ,igure 3 9ria=ial 0ells for / r 9est

9a le 6 / r 9esting Se5uences for nsaturated Sam"les

,igures 4* $*6and 16 show t "ical results of / r test on 1* O1* /1 and >1 at +(!*(!9 andD(! for whole sam"les. ,igures 1?* 1' and 1& illustrate the effects of var ing deviator stresses and


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aghdad soils and the Neural Networ: /ath Dor:s 9ool o=.It is elieved that / r of a cohesive soil is de"endent u"on its moisture content. 9o stud this

"henomenon for the "ro"osed constitutive model* the "redicted and measured / r at various moisture contentsdr of o"timum* o"timum* and wet of o"timum# were investigated. ,igures 1&* 2%* and 21 show com"arison of

the measured / r with the "redicted / r for 1* O1* /1 and >1 soils* res"ectivel . 9o "rove the ca"a ilitof the networ:* / r "redicted values for aghdad soils were com"ared with its corres"onding / r measured asillustrated and e="lained in ,igures 1&* 2% and 21. It can e o served that as the sam"le moisture contentincreases* / r "redicted the model reduces significantl and is generall close to the e="erimentall measured/ r * irres"ective of the sam"le moisture content. It can e o served that as the sam"le moisture content increases*/ r "redicted the model reduces significantl and is generall close to the e="erimentall measured / r *irres"ective of the sam"le moisture content. this model was "erformed "reviousl >im 2%%4# and


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Fig. (+ ) #esilient Mo$ulus From Mr la%oratory test For BZ1&ocation (D' )

70

75

80

85

90

95

100

0 20 40 60 80

De iator *tre ss (K a)

# e s i l i e n t M o $ u l u s ( M a )

Confining stress 41 kPa

Confining stress 21 KPa

Confining Stress 0 KPa

Fig. (, ) #esilient Mo$ulus From Mr la%oratory test For BM1&ocation (D' )

65

70

75

80

85

90

0 20 40 60 80

De iator *tress (K a)





Fig. (- ) #esilient Mo$ulus From Mr la%oratory test For BK1&ocation (D' )

40

45

50

55

60

65

0 20 40 60 80







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Fig. ( ) #esilient Mo$ulus From Mr la%oratory test For BZ1&ocation (' /)

60

65

70

75

80

0 10 20 30 40 50 60 70


# e s

i l i e n

t M o

$ u

l u s

( M

a

)

Confining stress 41 k Pa

Confining stress 21 KP a

Confining Stress 0 K Pa

Fig. (0 ) #esilient Mo$ulus From Mr la%oratory test For BB1&ocation (' /)

30

34

38

42

46

50

0 10 20 30 40 50 60 70


# e s

i l i e n

t M o

$ u

l u s

( M a

)


Confining stress 21 K Pa

Confining Stress 0 KP a

Fig. (1 ) #esilient Mo$ulus From Mr la%oratory test For BM1&ocation (' /)

50

55

60

65

70

75

80

0 10 20 30 40 50 60 70


# e s

i l i e n

t M o

$ u

l u s

( M a

)

Confining stress 41 kP a




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13$

Fig. (11 ) #esilient Mo$ulus From Mr la%oratory test For BK1&ocation (' /)

30

35

40

45

0 10 20 30 40 50 60 70


# e s

i l i e n t

M o

$ u

l u s

( M

a )


Confining stress 21 KP a

Confining Stress 0 K Pa

Fig. (12 ) #esilient Mo$ulus From Mr la%oratory test For BB1&ocation (3' )

15

20

25

30

35

40

0 10 20 30 40 50 60 70






Fig. (1! ) #esilient Mo$ulus From Mr la%oratory test For BM1&ocation (3' )

35

40

45

50

55

60

0 10 20 30 40 50 60 70







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Fig. (1" ) #esilient Mo$ulus From Mr la%oratory test For BK1&ocation (3' )

20

24

28

32

36

40

0 10 20 30 40 50 60 70






Fig. (1+ ) #esilient Mo$ulus From Mr la%oratory test For BZ1&ocation (3' )

30

34

38

42

46

50

0 10 20 30 40 50 60 70


# e s i l i e n t M o $ u l u s ( M

a )


Confining stress 21 K Pa

Confining Stress 0 KP a

Fig. (1 ) #esilient Mo$ulus From Mr la%oratory test For BB1,BZ1,BM1 &ocation (D' ) at Con4ining ressure "15 a

50

55

60

65

70

75

80

85

90

95

100

0 20 40 60 80


# e s

i l i e n

t M o

$ u

l u s

( M a

)

BB1BZ1

BM1

BK1

Fig. (1-) #esilient Mo$ulus From Mr la%oratory test For BB1,BZ1,BM1 &ocation (' /) at Con4ining ressure "15 a

40

50

60

70

80

90

100

0 10 20 30 40 50 60 70


# e s

i l i e n

t M o

$ u

l u s

( M a

)

BB1

BZ1

BM1

BK1

Fig. (1 ) #esilient Mo$ulus From Mr la%oratory test For BB1,BZ1,BM1 &ocation (3' ) at Con4ining ressure "15 a

30

35

40

45

50

55

60

0 10 20 30 40 50 60 70


# e s

i l i e n

t M o

$ u

l u s

( M a

)

BB1

BZ1

BM1

BK1


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A& Liquefaction Potentenial of Baghdad Soil ,Testing and Results-0 clic 9ria=ial tests were "erformed to evaluate the li5uefaction "otential and measured with guidance from thestandard test method for load controlled c clic 9ria=ial strength of soil S9/ + $311# see ,ig.2#. 9he testwas carried out on each soil at wet of o"timum which considered the most worst condition if there than +(! and(!9 conditions. ll sam"les should have e saturated efore starting the test* the U )alue of a out %.&% wasre5uired to "erform a c clic test. ;owever* if the s"ecimen too: longer than 1% da s to reach re5uired -)alue*the s"ecimen was tested due to time constraints. 9he li5uefaction test results are "resented in ta le ?. fterreaching re5uired level of saturation. 9o develo" c clic strength curves* confining "ressure ranged etween11$:!a to 2'%:!a and c clic stress ratios etween %.1%% to %.4%.9he c clic stress ratio 0Sramer*1&&6#.

Fig.(10) Measure$ an$ 6re$icte$ #esilient Mo$olus 4or all soils at D'

%

2%

4%

6%

'%

1%%

% 2% 4% 6% '% 1%%

Measured MrC MPa

P r e d

i c t e d M r C

M P a

@ine of E5ualit

Fig.(2 ) Measure$ an$ 6re$icte$ #esilient Mo$olus 4or all soils at ' /

%

2%

4%

6%

'%

1%%

% 2% 4% 6% '% 1%%

Measured MrC MPa

P r e d

i c t e d M r C M P a

@ine of E5ualit

Fig.(21) Measure$ an$ 6re$icte$ #esilient Mo$olus 4or all soils at 3'

%

2%

4%

6%

'%

1%%

% 2% 4% 6% '% 1%%

Measured Mr MPa

P r e

d i c t e d

M r C

M P a

@ine of E5ualit


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0S< V c cl. HR% 9a le ? Summar of li5uefaction test results on soil sam"les at D(!

S(I@

9W!E

0 clicStress

m"litude "si#

0onfining!ressure

"si#0S< 0 cles to @i5uefaction

1 ?.2 2% %.1' 243

O1 1%.4 2% %.26 +N@

/1 1%.' 2% %.2? +N@

>1 11.6 2% %.2& +N@+N@ +id Not @i5uef within 4%% c cles

,igures 22* 23* 24 and 2$ shows the li5uefaction tests results on sam"les 1* >1* O1 and /1.It could e concluded from test results that there is no "recautions for cohesive su grade should e ta:en

concerning li5uefaction.

-0.040

0.000

0.040

0.080

0.120

0.160

0.200

-0.1

-0.1

0.0

0.1

0.1

0.2

0.2

0.3

0.3

0 50 100 150 200 2 50 300

* t r a

i n ( i n

i n

)

# a

t i o o

4 7 8 c e s s

o r e

r e s s u r e

t o 9 n i t i a l C o n

4 i n

i n g

* t r e s s

( 6 s

i 6 s

i )

Cycles

!"ess Pore Press#re toConfining Stress

Strain $in%in&

'oa( Ce))

-40

-30

-20

-10

0

10

20

30

40

50

60

0 50 100 150 200 250 300 350 400 450 500

Cycles

: 8

i a l * t r e s s

( 6 s

i )

Load

-8

-6

-4

-2

0

2

4

6

8

0 10 20 30 40 50 60 70 80 90 100

Cycles

S t r e s s

, l b = i n ( -

Load

The curve continues in thesame context, whi e

access to 400 !"c e

,ig. 24# @i5uefaction test results of ?-$ soil

,ig. 22# @i5uefactiontest results of ?-$ soil

,ig. 23# @i5uefaction test results of 6 soil


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@& Conclusions and RecommendationsEvaluation of aghdad Soil rought from four locations was well studied to evaluate the resilient

modulus and the following conclusions were drawn1. 9he results of all e="erimental "rograms show the real need in evaluating the resilient modulus

ado"ting la orator methodolog .2. total colla"se of the "avement structure can occur due to large "lastic deformations arising in

the su grade soil due to e=tremel heav traffic loads.3.


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14%

mmG +ro"*Z merican ssociation of State ;ighwa and 9rans"ortation (fficials* Dashington* +.0.* 2%%4.?. S;9( 91%%-%3* YS"ecific ravit of Soils*Z merican ssociation of State ;ighwa and 9rans"ortation

(fficials* Dashington* +.0.* 2%%4.'. S;9( 92%'-&6* Y nconfined 0om"ressive Strength of 0ohesive Soil*Z merican ssociation of State

;ighwa and 9rans"ortation (fficials* Dashington* +.0.* 2%%4.&. S;9( / 14$-&1* 0lassification of soils and Soil- ggregate /i=tures for ;ighwa 0onstruction !ur"oses*Z

merican ssociation of State ;ighwa and 9rans"ortation (fficials* Dashington* +.0.* 2%%4.1%. S;9( 92?4-'2* YStandard /ethod of 9est for

14. S9/ +24'?-&'* YStandard 0lassification of Soils for Engineering !ur"ose nified Soil 0lassificationS stem#*Z nnual oo: of S9/ Standards* )ol. %4.%'* 2%%%.

1$. utalia* 9. S.* ;uang* J.* >im* +. U .* and 0roft* ,.* YEffect of /oisture 0ontent and !ore Dater !ressureuildu" on .* Yhasawneh* /ohammad li.* 2%%$* Laboratory Characteri ation of Cohesi!e Sub"rade Materials * 9hesis*+e"artment of 0ivil Engineering 9he niversit of :ron* 2%%$.

3%.>im* +. .* 1&&&* #n"ineerin" Properties $ffectin" %he Resilient Modulus of &ine'(rained Soils asSub"rade * Master %hesis, +e"artment of 0ivil and Environmental Engineering and eodetic Science 9he(hio State niversit .


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31.>im* +. .* 2%%4 )e!elopment of a Constituti!e Model for Resilient Modulus of Cohesi!e Soils, Ph ) )issertation * +e"artment of 0ivil and Environmental Engineering and eodetic Science 9he (hio State

niversit .32.@ee* D.* ohra* N. 0.* ltschaeffl* . .* and Dhite* 9. +.* YSu grade

4%./ohammad* @. N.* 9iti* ;. ;.* and ;erath* .* YEvaluation of


18/18

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The IISTE is currently hosting more than 30 peer-reviewed academic journals andcollaborating with academic institutions around the world. Theres no deadline for

submission. Prospective authors of IISTE journals can find the submissioninstruction on the following page: http://www.iiste.org/journals/ The IISTEeditorial team promises to the review and publish all the qualified submissions in afast manner. All the journals articles are available online to the readers all over theworld without financial, legal, or technical barriers other than those inseparable fromgaining access to the internet itself. Printed version of the journals is also availableupon request of readers and authors.

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Book publication information: http://www.iiste.org/book/

Recent conferences: http://www.iiste.org/conference/

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