specific gravity and gradation analysis

8/19/2019 Specific Gravity and Gradation Analysis

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University of South Alabama

Department of Civil, Coastal, and Environmental Engineering

TITLE OF PAPER GOES HERE IN ALL APS

Proctor Geotechnical, Inc.

Thomas Calhoun (Project Manager

Musaad !l"aiji

#i$u Chen

%amantha &amilton

!aron 'eatherford

CE )* + %ection *-

e"ruar$ -/, -*0

Table of ontents

Ta"le of Contents.............................................................................................................................ii

*


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1etter of Transmittal.......................................................................................................................iv

!"stract...........................................................................................................................................iv

Introduction......................................................................................................................................*

Introduction..................................................................................................................................*

2"jective......................................................................................................................................*

1iterature %urve$ and Theor$..........................................................................................................-

Introduction..................................................................................................................................-

Measurement of %pecific Gravit$ of %oil %olids.........................................................................

%pecific Gravit$, !"sorption, and Moisture Content...............................................................

3ul4 Densit$ and 5oid Content...............................................................................................)

Design Parameters II6 !ggregate Gradation !nal$sis.................................................................7

%ieve !nal$sis..........................................................................................................................7

8ominal Ma9imum !ggregate %i:e and ineness Modulus...................................................0

Mi9 Design and Trial 3atch !nal$sis..........................................................................................;

Mi9 Design and 3atching........................................................................................................;

!nal$sis of resh Mi9 Properties............................................................................................<

Preparation of Test %pecimens................................................................................................./

!nal$sis of ;=Da$ and -s ?atio.......................................................................................................................**

Procedural 2utline.........................................................................................................................*-

Determination of !ggregate Properties.....................................................................................*-

%pecific Gravit$ and !"sorption...........................................................................................*-

3ul4 Densit$ and @nit 'eight...............................................................................................*

!ggregate Gradation !nal$sis...................................................................................................*)

Trial 3atching and resh Mi9 Properties...................................................................................*7

Measurement of %lump..........................................................................................................*7

Measurement of the resh Mi9 3ul4 @nit 'eight.................................................................*0

Determination of the !ir Content in the Mi9.........................................................................*;Preparation and Curing of C$lindrical Test %pecimens.........................................................*;

;=Da$ and -s ?atio.............................................................................*<

-


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?esults and Discussion..................................................................................................................*/

!nal$sis of !ggregate Properties..............................................................................................*/

!ggregate Gradation !nal$sis...................................................................................................-

Mi9 Design and Trial 3atch !nal$sis........................................................................................-*

; and -


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Letter of Transmittal

Eric %teAard, Ph.D., P.E. e"ruar$ -/, -*0

Department of Civil Engineering@niversit$ of %outh !la"amaMo"ile, !1 00


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for use in proportioning of the material components. This method uses specific gravit$, a"sorption, and

moisture content of the aggregates to account for the e9act volume of each component in the mi9. The

resulting design met the minimum specifications hoAever, the average compressive strength e9ceeded

the target value. It is recommended that further research is conducted to improve the econom$ of the

mi9.

S"e!ifi! Gravity an# Grain Si$e %istribution Analysis

Intro#u!tion

Concrete mi9 design is the methodical process of determining the material components, properties, and

relative proportions, such that the final mi9 satisfies the necessar$ design specifications and is suita"l$

economical. Man$ different methods have "een esta"lished "ut each procedure varies in terms of the

data and measurements that are reBuired for the design. The properties of the individual components of

a mi9 can var$ Aith certain parameters and conditions, such as the specific t$pe of materials used, the

source from Ahich the$ are o"tained, and the conditions under Ahich the$ are stored. The given state of

some material properties can "e detrimental to the final mi9 if not properl$ accounted for. 'ith this in

mind, it is necessar$ to determine a means of accounting for material varia"ilit$ "$ identif$ing and

Buantif$ing the appropriate properties to "e used in design calculations. 2nce the initial design has

"een o"tained, it is critical to s$stematicall$ evaluate the performance of the product in order to

account for possi"le error and to ensure that the design criteria has "een met. It is also "eneficial for

providing insight into the overall econom$ of the design.

E9perimentation for the development of the reBuested concrete mi9 design Aas carried out in the

Construction Materials 1a"orator$ at the @niversit$ of %outh !la"ama. The data collection team

consisted of Conner Griffin and Thomas Calhoun. or a complete listing of the dates and times of the

specific e9perimental procedures, refer to !ppendi9 C at the end of the report.

Ob&e!tive

The goal of this report is to outline the theor$ and procedures used for determining the designed

concrete mi9 and to present the results of the e9perimental anal$sis of the component, fresh mi9

concrete, and hardened concrete properties. The e9perimental results Aill "e compared to e9isting and

7


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theoretical data in order to provide a relative datum for conve$ing an$ deviation from t$pical values.

Thoughts and ideas for the improvement of the resulting design and underl$ing procedures Aill also "e

discussed.

Literature Survey an# Theory

Intro#u!tion

!s previousl$ noted, there are man$ different methods that can "e used for developing a concrete mi9

design. !mong these are the ar"itrar$ volume method, the Aeight method, and the a"solute volume

method. or the ar"itrar$ volume method, the proportions for each component are specified ar"itraril$.

The Aeight method is similar to the a"solute volume method, "ut it is una"le to account for specificvolumes of the components in the mi9. The procedure descri"ed in this report, the a"solute volume

method, uses the specific gravit$ of each component, as Aell as other coarse and fine aggregate

properties, to account for the specific volume of matter that each component contri"utes to the mi9.

This alloAs for a ver$ precise and accurate means of concrete mi9 design.

The specific procedures defined "$ the a"solute volume method Aere officiall$ adopted "$ the

!merican Concrete Institute>s Committee -** (Michael %. Mamlou4, Proportioning of Concrete Mi9es

-**. The standard procedures for evaluation of the necessar$ design parameters used in the a"solute

volume method and the evaluation of a designed concrete mi9 Ahich are referenced in this report have

"een esta"lished "$ the !merican %ociet$ of &ighAa$ and Transportation 2fficials (!!%&T2 and the

!merican %ociet$ for Testing and Materials (!%TM. These standards aim to ensure that Bualities such

as Aor4a"ilit$, dura"ilit$, strength, and econom$ of a concrete mi9 design are consistentl$ attained.

The reBuired input parameters for the a"solute volume method include the folloAing6 nominal

ma9imum aggregate si:e, "ul4 specific gravit$, a"sorption, "ul4 densit$, moisture content, design air

content, and the fineness modulus of the fine aggregate. The a"solute volume method uses a statistical

approach to achieve the design compressive strength. It alloAs for the design strength and Aater tocement ratio of a mi9 to "e "ased upon the historical records of a designers past mi9es hoAever, Ahen

no past records are availa"le, reference can "e made to standard ta"ulated data and eBuations Ahich

provide conservative values that Aill ensure that the minimum strength reBuirements and other criteria

are met.

0


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'easurement of S"e!ifi! Gravity of Soil Soli#s

The specific gravit$ of a material is defined as the ratio of its densit$ to the densit$ of Aater. This

convention provides a relationship for the Aeight and volume of a su"stance to the unit Aeight of Aater.

In soil mechanics, the concept is particularl$ useful as it helps to facilitate the determination of varioussoil parameters in the a"sence of ph$sicall$ measured Buantities. T$pical values for specific gravit$ of

soil solids range from -.7 to -.< (The Transtec Group, Inc. -


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Grain si:e distri"ution is an important characteristic that must "e accounted for Ahen anal$:ing soil

samples. %oil performance is largel$ dependent on the gradation of the particles. The individual

particles that ma4e up a soil ma$ "e classified as gravels, sands, silts, cla$s, or organics and their

classification as such is primaril$ determined "ased on particle si:e. 'ith such diverse environments,

soils encompass a vast range of si:es, chemical structures, te9tures, and man$ other properties. 'ith

such diversit$, a standardi:ed soil classification s$stem Aas essential.31

5. ANALYSIS OF GRAIN SIZE DISTRIBUTION5.1. APPLICABLE ASTM STANDARDS

ASTM D422: Standard Test Method for Particle-Size Analysis of Soils ASTM D1140: Standard Test Method for Amount of Material in Soils iner

Than the !o" 200 #$%-m& Sie'e5.2. PURPOSE OF MEASUREMENT The (ur(ose of these tests is to determine the )rain size distri*ution #i"e"+ )rainsize

'ersus (ercent *y ,ei)ht& of soil and to determine the (ercenta)e of .nes #i"e"+material(assin) the !o" 200 sie'e& in soil" This information is used to classify the soil inaccordance ,ith the /ni.ed Soil lassi.cation System #/SS&"5.3. DEFINITIONS AND THEORY 5.3.1. Mechanca! Se"n#Soil consists of indi'idual (articles or )rains" rain size refers to the size of ano(enin)in a suare mesh throu)h ,hich a )rain ,ill (ass" Since all of the )rains in a massof soilare not the same size it is con'enient to uantify )rain size in terms of a

)radation cur'e"A )radation cur'e contains (oints corres(ondin) to a (articular )rain size and acorres(ondin) (ercent #*y ,ei)ht& of the soil )rains that are smaller than that)rain size"n the eam(le sho,n in i)" %"1 305 of the soil )rains are smaller than 0"16 mm" To (erform )rain size analysis of a dry )ranular soil #sand or )ra'el& mechanicalsie'in) is used and the soil is (assed throu)h a stac7 of sie'es" Any num*er ofsie'escan *e used *ut the size of the stac7 is ty(ically limited to si sie'es" Thecoarsest sie'eis at the to( of the stac7 follo,ed *y increasin)ly .ner sie'es *elo," A (an is

(laced*elo, the *ottom sie'e to collect the soil that (asses the .nest sie'e" 8y ,ei)hin)thefraction retained *y each sie'e (oints on the )radation cur'e can *e calculated"


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The standard e9perimental procedure for determining the "ul4 unit Aeight and void content is outlined

in the !%TM C-/ standard (!%TM International -/. The calculated values are given "$ the

folloAing eBuations6

Gs= M o

M o+( M a− M b),

(*

Gs20=G s K ,

#2&

,here: SSD Weight 9 saturated sam(le ,ei)ht ,ith all 'isi*le surface ,ater

remo'ed and

Dry Weight 9 sam(le ,ei)ht after heatin) to remo'e all ,ater from

(ermea*le

Moisture Content ( )=( Weight moist −Weight dryWeight dry )⋅100 , (7

Ahere6 Weight moist = the Aeight of a sample in the air dr$ or moist condition, and

Weight dry = the Aeight of an oven dried aggregate sample.

Bulk Density=Weight of Measure∧ Aggregate−Weight of Measure

Volume of Measure (0

!er"ent Voids=( (Bulk Dry #$G $ % & ' 2 ( )−Bulk DensityBulk Dry #$ G$ %& ' 2( )⋅100, (;

,here: & ' 2

(=¿ s(eci.c ,ei)ht of ,ater"

%esi)n Parameters II* A))re)ate Gra#ation Analysis

Sieve Analysis

! sieve anal$sis provides a measure of the particle si:e distri"ution of an aggregate. This procedure

involves passing an aggregate sample through a series of sieves Aith consecutivel$ smaller openings.

/


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!s a sample is processed, some particles are retained Ahile others pass on to "e retained on a smaller

sieve. The resulting gradation is then Buantified "$ the ratio of the amount retained on each sieve to the

total amount processed and the cumulative amount passing each sieve in the series. These values are

then used to o"tain the standard coarse aggregate si:e classification and fineness modulus. The grading

reBuirements for the !%TM si:e classifications are listed in the !%TM C standard (!%TM

International -. The e9perimental procedure for conducting a sieve anal$sis is descri"ed in the

!%TM C*0 standard (!%TM International -*). The calculated values for percent passing and

percent retained on each sieve are given "$6

!er"ent )etained=(Weight of #ie*e∧#am+le−Weight of #ie*e,otal#am+leWeight ) ⋅100,(


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Figure 2: %hoAs an e9ample of an aggregate gradation chart Aith the percent passing versus

sieve si:e (increasing to the right plotted for four different t$pes of gradations.

Nominal 'a+imum A))re)ate Si$e an# Fineness 'o#ulus

Data collected during the sieve anal$sis is also used to calculate the nominal ma9imum aggregate si:e

of the coarse aggregate and the fineness modulus for the fine aggregate. The nominal ma9imum

aggregate si:e is given as the first sieve si:e to retain less than ten percent of the graded sample. The

fineness modulus is defined as the sum of the cumulative percentages retained on the standard sieves

divided "$ one=hundred. These values are used to determine the amount of coarse aggregate in a mi9.

The procedure for the calculation of the fineness modulus is discussed in the !%TM C*0 standard

(!%TM International -*). The folloAing eBuation is used for the calculation6

er"ent )etained

Cumulati*e ! ¿¿¿ i¿∑ ¿

-ineness Modulus=¿

, (*

Ahere6 H(Cumulative Percent Retained i is for the standard sieve si:es outlined in the !%TM

C*0 standard.'i+ %esi)n an# Trial ,at!h Analysis

'i+ %esi)n an# ,at!hin)

**

%ource6 (Michael %. Mamlou4, Gradation %pecifications -**


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The components for a mi9 design include coarse aggregate, fine aggregate, cement, and Aater.

!dmi9tures ma$ also "e considered if the$ are necessar$ to achieve certain properties or are reBuested

"$ the client hoAever, their use Aill not "e discussed in this report. The process of determining the mi9

proportions using the a"solute volume method is defined "$ the !CI ?ecommended Practice -**.*

(!merican Concrete Institute *//*. This method involves a series of procedures in Ahich the

previousl$ discussed parameters are used to determine a ratio of the volume of the mi9 components to a

unit volume of concrete. The final step uses the a"sorption and moisture content of the aggregates to

correct the design for the actual amount of Aater reBuired for the mi9. 2nce the correct proportions are

o"tained, a trial "atch of concrete is mi9ed. This alloAs the designer to e9perimentall$ evaluate

properties of the design and to ensure that the design specifications are met. ! "atch can "e hand mi9ed

or mi9ed Aith the aid of a mechanical mi9er. 'hen "atching concrete, care should "e ta4en to avoid

o"taining an inconsistent mi9ture. The !%TM C*/- standard for mi9ing and curing concrete lists

several steps and precautionar$ measures that should "e folloAed to ensure that a Bualit$ product is

attained (!%TM International -*7.

Analysis of Fresh 'i+ Pro"erties

!nal$sis of the fresh mi9 properties of a design involves measuring the slump, fresh mi9 unit Aeight,

and air content. The slump of fresh mi9ed concrete is a measure of the Aor4a"ilit$ or ease of placing.

The !%TM C*) standard outlines the procedure for the measurement of slump (!%TM International

-*7. This procedure involves placing fresh mi9ed concrete into a specified mold and Buic4l$

removing the mold to measure the vertical distance that the mi9 settles. Man$ different factors can

affect the slump of a designed mi9 "ut (since admi9tures are not "eing considered in this report the

most significant contri"uting factor is the Aater to cement ratio. !s the amount of Aater in a mi9 is

increased, the slump of the mi9 is also increased. 'hile increasing the Aater to cement ratio ma$ "e

"eneficial to the Aor4a"ilit$ needs, it ma$ have significant repercussions for other properties.

Increasing the Aater content of a mi9 can result in decreased strength, increased segregation of mi9

constituents, and dela$ed set time. This is onl$ a feA of the considerations that the designer must ta4e

into account.

Though the mi9 constituents consist of onl$ aggregate, cement, and Aater, it is inherent that air voids

Aill also "e present. The design process attempts to account for the volume of air that Aill "e trapped in

the mi9 as a result of the "atching process. !ir voids in a hardened concrete sample can reduce its

strength and dura"ilit$. It is therefore necessar$ to measure the amount of air present in a mi9. The

!%TM C-* standard descri"es accepta"le procedures for determining the air content of freshl$ mi9ed

concrete using the pressure method (!%TM International -*7. The pressure method uses the

*-


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relationship "etAeen volume and pressure from 3o$le>s laA to measure the volume change in a

compressed sample (Michael %. Mamlou4, Measuring !ir Content in resh Concrete -**.

The unit Aeight of a fresh mi9 provides a means of determining the $ield of a concrete mi9 design. The

procedure for calculating the unit Aeight of a freshl$ mi9ed concrete sample is descri"ed in the !%TM

C*< standard (!%TM International -*). The calculated value is given "$6

.nit Weight = /et weight of "on"rete

Volume of measure. (**

Pre"aration of Test S"e!imens

2nce the fresh mi9 properties of a design have "een determined, c$lindrical test specimens are then

prepared for future evaluation of hardened concrete properties. The !%TM C* standard outlines the

procedure for the preparation and curing of compression test samples (!%TM International -*7. The

fresh mi9 is placed in the ()=in diameter


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Com+ressi*e #trength= Ma0 1oad at -ailure

A*erage Cross #e"tional Area

. (*-

'o#ulus of Elasti!ity

The modulus of elasticit$ provides a measure of hoA much load a material can incur "efore it reaches

its elastic limit. The elastic limit of a material is defined as the largest stress that does not cause a

measura"le permanent deformation (Michael %. Mamlou4, Materials for Civil and Construction

Engineers -**. Figure 3, shoAs t$pical stress=strain relationships for concrete samples Aith different

Aater to cement ratios. 8otice hoA there seems to "e a semi=linear relationship until a specimen is

loaded "e$ond a certain stress. This point is appro9imatel$ the elastic limit. The elastic modulus can "e

appro9imated as the slope of the semi=linear portion of a curve.

Figure 3: T$pical stress=strain relationships for concrete specimens Aith var$ing Aater to cement ratios tested in compression.

%ource6 (Michael %. Mamlou4, Materials for Civil and Construction Engineers -**

2ne procedure for determining the modulus of elasticit$ of a sample is presented in the !%TM C)0/

standard (!%TM International -*). The value o"tained in this method is 4noAn as the chord

modulus. ! chord modulus uses tAo points on the interior of a curve to calculate the linear slope "etAeen those tAo points. The chord modulus is given "$6

2"hord= 3

2−3

1

42−0.00005( +si ) (*

*)


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Ahere6 K* stress at a strain of .7,

K- stress at fort$ percent of the design compressive strength, and

L- the strain at fort$ percent of the design compressive strength.

The !CI *< code recogni:es a graphical method of determining the elastic modulus. This method is

used to find a value termed the secant modulus (!merican Concrete Institute *///. The secant

modulus applies a "est fitN linear curve to a plot of the stress=strain data Ahich displa$s a ma9imum

load of fort$ percent of the ultimate load. The slope of this curve is ta4en to "e the secant modulus.

Theoretical values for the modulus of elasticit$ can "e used as a means of comparing e9perimental

results to t$pical values. The tAo theoretical values for the elastic modulus Ooung>s and !CI>s

theoretical modulus respectfull$ (!merican Concrete Institute *///Q that Aill "e discussed are given

"$6

2theor=w"1.5

%33%√ f 5

" ( +si) , (*)

2theor=57,000%√ f 5 " ( +si ) (*7

Ahere6 wc the unit Aeight of the fresh mi9, and

f Rc the compressive strength.

Poisson1s Ratio

Poisson>s ratio is a measure of the proportionalit$ of a9ial to transverse strain for materials that are

loaded Aithin their elastic limit. !s a material deforms Aith respect to an a9is, there must "e a resulting

deformation along the a9is> that are perpendicular to it in order to satisf$ conservation laAs. The ratio

of these deformations is a function of "onding on the molecular level. %ince no tAo materials are

e9actl$ ali4e, Poisson>s ratio Aill var$ from one material to the ne9t. or freshl$ mi9ed concrete, the

desira"le range is .-=.-*. The !%TM C)0/ standard descri"es the procedure used for determining

Poisson>s ratio. or e9perimentall$ determined values of strain,

Poisson>s ratio is given "$6

6=4t 2−4t 142−41

(*0

Ahere6 L* .7,

Lt* transverse strain at L*,

*7


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Lt- transverse strain at fort$ percent of the design compressive strength, and

L- a9ial strain at fort$ percent of the design compressive strength.

Pro!e#ural Outline

%etermination of A))re)ate Pro"erties

S"e!ifi! Gravity an# Absor"tion

Determination of specific gravit$ and a"sorption folloAed the !%TM C*-; standard (!%TM

International -*7. !ppendi9 3 contains the data used for calculations. The folloAing eBuipment Aas

used for the e9perimental procedure6

• 'ater tan4 Aith overfloA apparatus,

• Digital "alance,

• 'ire mesh "as4et, and

• %uspending apparatus.

or this e9periment, a representative aggregate sample Aas su"merged in Aater for appro9imatel$

tAent$=four hours. The sample Aas then removed from the saturation cham"er and toAel dried to

remove the surface moisture. The Aeight of the sample in the %%D condition Aas then recorded. The

sample Aas then placed into a Aire mesh "as4et and suspended from a "alance. ! Aater tan4 Aith an

overfloA apparatus Aas hoisted up to the sample until it Aas completel$ su"merged. !fter Aaiting toensure that an$ entrapped air Aas released and all displaced Aater Aas evacuated from the tan4, the

sample Aeight in Aater Aas recorded. ! t$pical assem"l$ for measurement of the su"merged Aeight is

shoAn in Figure . inall$, the sample Aas placed in an oven at appro9imatel$ **FC for tAent$=four

hours and the oven=dried Aeight Aas recorded. The data Aas then processed for determination of

specific gravit$ and a"sorption.

*0


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Figure 4! This figure shoAs a t$pical Aater tan4 Aith overfloA apparatus, digital "alance, Aire mesh "as4et,

and the suspending apparatus used for determining the specific gravit$ of a coarse aggregate.(Michael %. Mamlou4, Materials for Civil and Construction Engineers -**

,ul2 %ensity an# Unit (ei)ht

Determination of "ul4 densit$ and "ul4 unit Aeight of the aggregates folloAed the !%TM C-/ standard

(!%TM International -/. !ppendi9 3 contains the data used for calculations. The folloAing

eBuipment Aas used for the e9perimental procedure6

• 3alance,

• Tamping rod, and a

• ?igid metal container to serve as a measure.

irst, the volume of the measure Aas determined "$ measuring its Aeight empt$ and its Aeight Ahile

filled Aith Aater. The aggregate Aas then placed into the measure in multiple la$ers. !fter each la$er

Aas placed, it Aas rodded -7 times Aith a tamping rod to ensure standard compaction. 2nce the

measure Aas filled Aith the aggregate sample, its Aeight Aas then recorded. The data Aas then used to

calculate the "ul4 densit$ and unit Aeight of the aggregate. Figure " shoAs t$pical eBuipment used for

the procedure.

Figure 5! This figure shoAs an aggregate sample "eing rodded (left, and Aeighed for the "ul4 unit Aeight (right.(Michael %. Mamlou4, Materials for Civil and Construction Engineers -**

A))re)ate Gra#ation Analysis

The aggregate gradation procedure folloAed the !%TM C*0 standard (!%TM International -*).

!ppendi9 3 contains the data used for calculations. The folloAing eBuipment Aas used for

e9perimentation6

• 8est of sieves Aith a pan and cover,o Coarse ( - in, * S in, * in, in, S in, 8o.), 8o.


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• 1arge mechanical sieve sha4er.

irst, representative samples of coarse and fine aggregate Aere o"tained. The Aeight of each sample

Aas then recorded. or the gradation anal$sis, the sieves Aere chec4ed to ensure that no particles

remained from previous use. !fter inspecting the sieves, each sieve Aas Aeighed and the Aeights Aere

recorded. The sieves Aere then stac4ed in ascending order "$ mesh si:e. The samples Aere then placed

on the top sieve and agitated "$ a mechanical apparatus for five minutes. Figure # shoAs t$pical

eBuipment used for a sieve anal$sis. !fter the agitation process, the Aeights of the sieves Aith the

retained sample Aere recorded. The measurements o"tained Aere then used for the calculations and

anal$sis. The aggregate si:e num"er Aas determined "$ referring to the !%TM C standard (!%TM

International -.

Figure 6 ! This figure shoAs (from left to right t$pical sieves "eing loaded Aith the sample,a ?o=Tap mechanical sieve sha4er, and a t$pical large mechanical sha4er.

(Michael %. Mamlou4, Materials for Civil and Construction Engineers -**

Trial ,at!hin) an# Fresh 'i+ Pro"erties

'easurement of Slum"

Determination of slump of the fresh mi9ed concrete folloAed the !%TM C*) standard (!%TM

International -*7. !ppendi9 3 contains the data used for calculations. The folloAing eBuipmentAas used for the procedure6

• mold in the form of a lateral surface frustum, and a

• tamping rod.

*


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irst, a sample of the freshl$ mi9ed concrete Aas placed into a mold in three la$ers and rodded "etAeen

each consecutive la$er. The mold Aas then cleared of an$ e9cess mi9 at the top of the frustum. 8e9t,

the mold Aas raised at a specified rate, and the concrete alloAed to su"side. 'ith the mold set aside the

mound of fresh mi9, the tamping rod Aas placed on top of the mold and used as a datum for the

measurement. Figure $ displa$s the t$pical eBuipment used, rodding procedure, and measurement. The

vertical distance "etAeen the original and displaced position of the center of the top surface of the

concrete Aas measured and reported as the slump of the concrete.

Figure 7 ! This figure illustrates a t$pical slump mold and tamping rods, and the procedure used to determine the slump. 2n the left is a

mold "eing rodded in "etAeen la$ers. The picture on the right shoAs a measurement "eing ta4en after the mold has "een removed.


'easurement of the Fresh 'i+ ,ul2 Unit (ei)ht

Determination of the "ul4 unit Aeight of the fresh mi9 folloAed the !%TM C*< standard (!%TM

International -*). !ppendi9 3 contains the data used for calculations. The folloAing eBuipment Aas

used for the procedure6

• 3alance,

• Measure, and• Mallet.

To measure "ul4 unit Aeight, a sample of the fresh concrete Aas rodded in a measure of predetermined

Aeight and volume. !fter rodding each la$er, the sides of the measure Aere tapped Aith a mallet to

release an$ large air "u""les that ma$ have "een trapped. The measure Aas then Aeighed and the unit

Aeight Aas calculated.

*/


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%etermination of the Air ontent in the 'i+

The !%TM C-* standard Aas used for determination of the air content of the fresh mi9 (!%TM

International -*7. The folloAing eBuipment Aas used for the e9perimental procedure6

•T$pe 3 air meter,• Tamping rod,

• Mallet, and

• %tri4e off "ar.

or the procedure, the T$pe 3 air meter ( Figure #% Aas filled Aith the fresh mi9 in three la$ers. The

mi9 Aas rodded "etAeen each to ensure proper compaction. !fter each la$er Aas rodded, the sides of

container Aere tapped Aith a mallet to rid the mi9 of an$ large trapped air poc4ets. The rim of the

container Aas then cleaned to ensure an air tight seal. 'ith the lid placed, the apparatus Aas then filled

Aith Aater. The container Aas then pressuri:ed and the air content Aas recorded.

Figure 8: This figure shoAs a t$pical T$pe 3 air meter and the reading o"tained from the e9perimental procedure.


Pre"aration an# urin) of ylin#ri!al Test S"e!imens

The preparation and curing of test specimens folloAed the !%TM C*/- standard (!%TM International

-*7. The folloAing eBuipment Aas used for the procedure6

• < non=a"sor"ent c$lindrical molds,

• Tamping rod,

• 'ater tan4 filled Aith lime saturated Aater.

or the trial "atch, eight ()=in diameter 9


21/41

-.%ay an# /0.%ay on!rete Testin)

Avera)e om"ressive Stren)th

The !%TM C/ standard Aas used for determination of the average compressive strength of the seven

and tAent$=eight da$ cured samples (!%TM International -*7. !ppendi9 3 contains the data used for

calculations. The folloAing eBuipment Aas used for the e9perimental procedure6

• 1oading machine,

• 8eoprene caps, and a

• Computer Aith data collection softAare.

To determine the average compressive strength, the samples Aere removed from the curing tan4 and

dried. Measurements Aere then ta4en for the diameter and height of each sample. The samples Aere

then placed into the loading machine and compressed at a rate of )) l"sJsec. !fter loading the samples

to the point of failure, the ma9imum load applied to each sample Aas recorded.

Figure 9: This figure shoAs a t$pical loading machine used for compression testing of concrete specimens.


The Elasti! 'o#ulus an# Poisson1s Ratio

The !%TM C)0/ standard Aas folloAed for the procedure of determining the modulus of elasticit$ and

Poisson>s ratio of the seven and tAent$=eight da$ cured samples. !ppendi9 3 contains the data used for

calculations. The folloAing eBuipment Aas used for e9perimentation6

• 1oading machine,

• Compressometer Aith an e9tensometer,

• 8eoprene caps, and a

•Computer Aith data collection softAare.

or the procedure, the sample Aas outfitted Aith a compressometer and e9tensometer "efore "eing

placed into the loading machine. 2nce placed in the device, the sample Aas then loaded to half of the

predetermined ultimate compressive strength. 8o data Aas recorded for the first loading, as this Aas

necessar$ to ensure that the eBuipment Aas properl$ Aor4ing. The sample Aas then loaded a second

-*


22/41

time as data Aas collected for the calculation of the elastic modulus and Poisson>s ratio. Figure &

displa$s a t$pical compressometer Aith an e9tensometer that can "e used for the procedure.

Figure 10: This figure shoAs a t$pical compressometer Aith an e9tensometer that Aould "e used for

determining the modulus of elasticit$ and Poisson>s ratio.

Results an# %is!ussion

Analysis of A))re)ate Pro"erties

The results for the calculation of specific gravit$ and a"sorption of the coarse aggregate are

summari:ed in 'a(le 1. The results also indicate that the values for the "ul4 densit$ and void content of

the coarse aggregate are *- l"Jft and 0.7 percent respectfull$. The fineness modulus for the fine

aggregate sample Aas found to "e -.;-

Table 1! Calculated values for "ul4 specific gravit$ (dr$, %%D, and apparent and a"sorption.

A))re)ate Gra#ation Analysis

!ppendi9 3 contains the ta"ulated values for the percent retained, cumulative percent retained, and

percent passing each consecutive sieve si:e for the coarse and fine aggregate samples. The sieve

anal$sis for the coarse aggregate sample indicates that the closest si:e classification "ased on the

--

S"e!ifi! Gravity an# Absor"tion

3ul4 %.G.=Dr$ -.7;

3ul4 %.G.=%%D -.0

!pparent %.G. -.00

!"sorption (U *.


23/41

!%TM grading reBuirements is 8o. ;. This can "e graphicall$ visuali:ed "$ referring to the semi=log

gradation chart in Figure 11. The standard limiting values for the sample classification are plotted Aith

the calculated sample gradation.

0"00

10"00

20"00

30"00

40"00

%0"00

:0"00

$0"00

60"00

;0"00

100"00

100

$0

1%%

100

;0

40

00

Semilo) Gra#ation hart for oarse Sam"le).;7 mm (8o. ) -.0 mm (8o.


24/41

Coarse !ggregate *77 *7)

ine !ggregate /


25/41

Table 5: Data collected during the tAent$=eight da$ compressive strength test Aith the

ma9imum load, the compressive strength, and "rea4 t$pe.

Loa# %ata

Sam"le 'a+ Loa# 3lbs6 om"ressive Stren)th 3"si6 ,rea2 Ty"e

7 /7 ;)/ @ndetermined

/ //s ratio Aere found to "e .*< and

.-0 respectfull$. The values for the theoretical and e9perimentall$ determined elastic moduli are

summari:ed in 'a(les # and &.

Table 6: 5alues for the seven da$ theoretical and e9perimentall$ determined elastic moduli.

'etho# 'o#ulus of Elasti!ity 3"si6

Se!ant E e+"4 ).E0

hor# E e+" .;7E0

9oun)1s E Theor4 ).)7E0

AI Se!ant E Theor4 ).)E0

Table 7: 5alues for the tAent$=eight da$ theoretical and e9perimentall$ determined elastic moduli.

'etho# 'o#ulus of Elasti!ity 3"si6

Se!ant E e+"4 ).E0

hor# E e+" ).7E0

9oun)1s E Theor4 7.7E0

AI Se!ant E Theor4 )./-E0

Figures 12 and 13 shoA the stress versus strain curves used for determining the secant moduli. The

slope of the "est fitN (dotted lines are the secant modulus value. The eBuation for the lines are also

displa$ed on the graphs.

-7


26/41

0"00


27/41

J< inch sieve. The calculated value Aas found to "e eight$ percent passing hoAever, the standard

reBuires that the value "e in the range of fort$ to sevent$ percent. !ll other values for percent passing

Aere in the standard range for a 8o.; classification.

The e9perimental results for the calculation of air content, unit Aeight, and slump Aere consistent Aith

the design specifications and other pu"lished data. !lthough the measured values for slump and air content Aere satisfactor$, the compressive strength of the mi9 far e9ceeded the design specification.

%ince no historical data Aas availa"le for the design of the mi9, conservative values Aere selected for

input parameters in order to ensure that the minimum average compressive strength Aould "e attained.

If the econom$ of the design is a concern, it is recommended that a neA mi9 design is considered.

'hile the current design Aill satisf$ Aor4a"ilit$, air content, and strength reBuirements, increasing the

Aater content Aill result in reduced costs Ahile maitaining an accepta"le average compressive strength.

The calculated values for the e9perimentall$ determined elastic moduli Aere found to "e similar to the

theoretical values. The calculated value of Poisson>s ratio Aas .*< at seven da$s and .-0 at tAent$=

eight da$s. 8either of these values Aere in the normal range of .- to .-*. It should "e noted that

during the data collection process for Poisson>s ratio, recording of the load data "egan after the sample

had surpassed the necessar$ strain of 7.E=7. or the calculation, the loAest recorded stress and strain

values Aere used.

-;


28/41

Referen!es

!merican Concrete Institute. *///. V3uilding Code ?eBuirements for %tructural Concrete6 (!CI *va+ora(le -oisture Content of )ggregate

(y 0rying . 'est Conshohoc4en, P!6 AAA.astm.org.

W. -. )'- tandard C33, /+ecification for Concrete )ggregates/ . 'est Conshohoc4en, P!6

AAA.astm.org.

Michael %. Mamlou4, Xohn P. YanieAs4i. -**. V!"sorption.V In -aterials for Civil and Construction

>ngineers, "$ Michael %. Mamlou4 and Xohn P. YanieAs4i, *;). @pper %addle ?iver, 8eA

Xers$6 Pearson Education.

Michael %. Mamlou4, Xohn P. YanieAs4i. -**. VGradation %pecifications.V In -aterials for Civil and

Construction >ngineers, "$ Michael %. Mamlou4 and Xohn P. YanieAs4i, *


29/41

W. -**. -aterials for Civil and Construction >ngineers. @pper %addle ?iver, 8eA Xers$6 Pearson

Education.

Michael %. Mamlou4, Xohn P. YanieAs4i. -**. VMeasuring !ir Content in resh Concrete.V In

-aterials for Civil and Construction >ngineers, "$ Michael %. Mamlou4 and Xohn P YanieAs4i,

-;-=-;. @pper %addle ?iver, 8eA Xers$6 Pearson Education.

Michael %. Mamlou4, Xohn P. YanieAs4i. -**. VProportioning of Concrete Mi9es.V In -aterials for

Civil and Construction >ngineers, "$ Michael %. Mamlou4 and Xohn P. YanieAs4i, -);. @pper

%addle ?iver, 8eA Xers$6 Pearson Education.

-/


30/41

A""en#i+


31/41

A""en#i+ A* %ummar$ of Calculations

Bulk Dry # $G $= Dry Weight

(##DWeight −Weight ∈ ' 2 (),

(*

Bulk ##D# $ G $= ##D Weight

(##DWeight −Weight ∈ ' 2 (),

(-

A++arent # $G $= Dry Weight

( Dry Weight −Weight ∈ ' 2(), (

Absor+tion ( )=( ##D Weight − Dry Weight Dry Weight ) ⋅100 , #)&

MoistureContent ( )=( Weight moist −Weight dryWeight dry )⋅100 , (7

Bulk Density=Weight of Measure∧ Aggregate−Weight of Measure

Volume of Measure (0

!er"ent Voids=

( (Bulk Dry #$G $ % &

' 2 ( )−Bulk Density

Bulk Dry #$ G$ %& ' 2( )⋅ 100,

(;

!er"ent )etained=(Weight of #ie*e∧#am+le−Weight of #ie*e,otal#am+leWeight ) ⋅100, (


32/41

.nit Weight = /et weight of "on"rete

Volume of measure. (**

Com+ressi*e #trength= Ma0 1oad at -ailure

A*erage Cross #e"tional Area

. (*-

2"hord= 3

2−3

1

42−0.00005( +si ) (*

2theor=w"1.5

%33%√ f 5

" ( +si) , (*)

2theor=57,000%√ f 5 " ( +si ) (*7

6=4t 2−4t 1

42−41 (*0

A""en#i+ ,* Data Collected During E9perimentation

%ata olle!te# for al!ulation of S"e!ifi! Gravity an# Absor"tion

(ei)ht 3lbs46

'easure .7

'easure :5 SS% Sam"le


33/41

%ata olle!te# %urin) Sieve Analysis

Fine A))re)ate

Sieve Si$e Per!ent Retaine# umulative Per!ent Retaine# Per!ent Passin)

850> * * //No4 ? * - /<

No4 0 < * /No4 7@ *- -- ;<No4 8 - )0 7)No4 B ); /- <No4 7 ; // *Pan .


34/41

%ata olle!te# %urin) -.%ay on!rete Testin)

S"e!imen Si$e

Sam"le C %iameter 3in6 Hei)ht 3in6

7 ).-7


35/41

Stress an# Strain %ata Use# for al!ulations

DT7 *./*E=7

DT/ *.-E=)

D7 ;.))E=7

D/ ).7;E=)

7


36/41

A""en#i+ * Photographs of %pecimens !fter ailure

- %ay on!rete Tests Photos

0


37/41

/0 %ay on!rete Tests Photos

;


38/41


39/41

/


40/41

A""en#i+ %* Calendar of E9perimental Procedures

E+"erimental Pro!e#ure %ate

!ggregate Testing + %pecific Gravit$, @nit 't., !"sorption %eptem"er *0, -*7

!ggregate Testing + Gradation %eptem"er -, -*7

Concrete 3atching Aith resh Properties Testing 2cto"er -*, -*7

;=Da$ Concrete Testing 2cto"er -


41/41

A""en#i+ E* Group Mem"er Contri"utions

Tas2 Thomas alhoun onnor Griffin

Ta"le of Contents 7 7

1etter of Transmittal

specific gravity and gradation analysis

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