2. Cement Lecturegag

7/28/2019 2. Cement Lecturegag

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Concrete Technology

VCB 2023

Cement


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Learning Outcome

To evaluate the properties of concreteconstituent materials.


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Definition

In BS EN 197-1, cement is defined as:

A hyd raul ic bind er, i .e. a f inely ground inorganicmater ial which , when m ixed w ith water, forms apaste which sets and hardens by means ofhydraul ic react ions and processes and which,after hardening, retains i ts s trength and s tabi l i tyeven under water.

Factory produced EN 197 cements are given thedesignation CEM

In British Standards, mixer combinations are giventhe designationCnot CEM


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History of Cement

In 1824, Joseph Aspdin, a British

(Leeds) stone mason, obtained a

patent for a cement he produced in his

kitchen.

The inventor heated a mixture of finely

ground limestone and clay in his

kitchen stove and ground the mixtureinto a powder create a hydraulic

cement-one that hardens with the

addition of water.


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History of Cement

Aspdin named the product Portland

cement because it resembled a stone

quarried on the Isle of Portland off the

British Coast.

With this invention, Aspdin laid the

foundation for today's Portland cement

industry.

Cement is so fine that one kg of cement contains more

than 300 billion grains


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Basic Composition

The raw materials required to produce Portland cement

are found and exploited in nearly all parts of the world,which is a significant reason for its universal importance

as a building material.

Table 1 indicates the standard mineralogical composition

of Portland cement and Table 2 indicates its standard

chemical composition.
http://sres-associated.anu.edu.au/fpt/cfb/cement.htmlhttp://sres-associated.anu.edu.au/fpt/cfb/cement.htmlhttp://sres-associated.anu.edu.au/fpt/cfb/cement.htmlhttp://sres-associated.anu.edu.au/fpt/cfb/cement.htmlhttp://sres-associated.anu.edu.au/fpt/cfb/cement.htmlhttp://sres-associated.anu.edu.au/fpt/cfb/cement.htmlhttp://sres-associated.anu.edu.au/fpt/cfb/cement.htmlhttp://sres-associated.anu.edu.au/fpt/cfb/cement.html


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Basic Composition

Chemical NameCommon

NameChemical Notation

Abbreviated

Notation

Mass Contents

(%)

tricalcium silicate alite 3CaO.SiO2 C3S 38-60

dicalcium silicate belite 2CaO.SiO2 C2S 15-38

tricalcium

aluminatebelite 3CaO.Al2O3 C3A 7-15

tetracalcium

aluminoferite celite 4CaO.Al2O3.Fe2O3 C4AF 10-18

pentacalcium

trialuminatecelite 5CaO.3Al2O3 C4AF 1-2

calcium sulphate

dihydrategypsum CaSO4.2H2O CSH2 2-5

Table 1 Mineralogical Composition of Portland Cements (Brandt, 1995)
http://sres-associated.anu.edu.au/fpt/cfb/references.htmlhttp://sres-associated.anu.edu.au/fpt/cfb/references.html


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Basic Composition

Tricalcium Silicate

(50%)

Dicalcium Silicate

(25%)

Tricalcium Aluminate

(12%)

Tetracalcium Aluminoferrite

(8%)

Gypsum

(3.5%) Other

(1.5%)


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Basic Composition

Chemical

NameCommon Name

Chemical

Notation

Abbreviated

Notation

Mass

Contents(%)

calcium oxide lime CaO C 58-66

silicon dioxide silica SiO2 S 18-26

aluminium

oxidealumina Al2O3 A 4-12

ferric oxides iron Fe2O3 + FeO F 1-6

magnesium

oxidemagnesia MgO M 1-3

sulphur

trioxide

sulphuric

anhydriteSO3 S 0.5-2.5

alkaline oxides alkalis K2O and NaO2 K + N


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Manufacturing of Cement

Producing a cement that meets specific chemicaland physical specifications requires carefulcontrol of the manufacturing process.

The first step in the Portland cement

manufacturing process is obtaining rawmaterials. Generally, raw materials consisting ofcombinations of limestone, shells or chalk, andshale, clay, sand, or iron ore are mined from aquarry near the plant. At the quarry, the rawmaterials are reduced by primary and secondarycrushers.

Stone is first reduced to 5-inch size (125-mm),then to 3/4-inch(19 mm). Once the raw materialsarrive at the cement plant, the materials areproportioned to create a cement with a specificchemical composition.


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Type of Manufacturing

Wet Process

Dry Process - 74% of cement produced

Preheater/Precalciner Process


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Dry Process

In the dry process, dry raw materials are

proportioned, ground to a powder, blendedtogether and fed to the kiln in a dry state.

In the wet process, a slurry is formed by addingwater to the properly proportioned raw materials.

The grinding and blending operations are thencompleted with the materials in slurry form. Afterblending, the mixture of raw materials is fed intothe upper end of a tilted rotating, cylindrical kiln.


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In the dry process, dry raw materials areproportioned, ground to a powder, blendedtogether and fed to the kiln in a dry state.

In the wet process, a slurry is formed byadding water to the properly proportionedraw materials. The grinding and blendingoperations are then completed with thematerials in slurry form.

After blending, the mixture of raw materialsis fed into the upper end of a tilted rotating,cylindrical kiln. The mixture passes throughthe kiln at a rate controlled by the slope androtational speed of the kiln.


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Burning fuel consisting of powdered coal ornatural gas is forced into the lower end of thekiln.

Inside the kiln, raw materials reachtemperatures of 1430oC to 1650oC. At1480oC, a series of chemical reactions causethe materials to fuse and create cementclinker-grayish-black pellets, often the size ofmarbles.

Clinker is discharged red-hot from the lowerend of the kiln and transferred to varioustypes of coolers to lower the clinker tohandling temperatures.


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The Cement is Ready for Market


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Cement Standards

BS EN 197-1:2000 (Inc. Amendment No.1:2004)

Composition, specifications and conformity criteria for

common cements

BS EN 197-4:2004

Composition, specifications and conformity criteria for

low early strength blast furnace cements

BS EN 196-series

Methods of testing cement


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Cement Standards

Cements are factory produced materials primarilyconforming to BS EN 197-1 or BS EN 197-4

Some cements, such as Sulphate-resisting Portlandcement (SRPC) are however, still covered by residualBritish Standards

There is a wide range of cements ranging from simplePortland cement to Composite cements containing upto three major constituents

Cements may be produced by inter-grinding or blendingthe constituents at the cement works

Cements can be CE marked against BS EN 197standards using BS EN 197-2 Conformity evaluation


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Types of Portland Cement

Different types of Portland cement are manufactured to

meet various physical and chemical requirements.

The American Society for Testing and Materials (ASTM)

Specification C-150 provides for eight types of Portland

cement.

BS EN 197-1 specified Five main classes of Portland

cement

However, Both BS EN and ASTM specified some other

types of cements for special functions.


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Types of BS EN 197-1Portland

Cement

Composite cementsCEM V

Pozzolanic cements (CEM IV/A, CEM IV/B)CEM IV

Blastfurnace cements (CEM III/A, CEM III/B)CEM III

Portland-composite cements including:

-Portland-fly ash cement (CEM II/A-V, CEM II/B-V)

-Portland-slag cement (CEM II/A-S, CEM II/B-S)

-Portland-limestone cement (CEM II/A-L (LL),CEM II/B-L (LL)

CEM II

Portland cementCEM I

DescriptionDesignation

Composite cementsCEM V

Pozzolanic cements (CEM IV/A, CEM IV/B)CEM IV

Blastfurnace cements (CEM III/A, CEM III/B)CEM III

Portland-composite cements including:

-Portland-fly ash cement (CEM II/A-V, CEM II/B-V)

-Portland-slag cement (CEM II/A-S, CEM II/B-S)

-Portland-limestone cement (CEM II/A-L (LL),CEM II/B-L (LL)

CEM II

Portland cementCEM I

DescriptionDesignation


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How are Cements Designated

Example: CEM II/A-LL 42,5 NExample: CEM II/A-LL 42,5 N

CEM II: Portland composite cement

A-LL: A signifies low proportion ofsecond constituent (6-20% in this case)

L orLL signifies limestone as the

second main constituent (LL signifies

high purity limestone)42,5 N: Cement strength class 42,5

Normal strength development

Portland-limestone cementPortland-limestone cement

Example: CEM II/A-LL 42,5 NExample: CEM II/A-LL 42,5 N

CEM II: Portland composite cement

A-LL: A signifies low proportion ofsecond constituent (6-20% in this case)

L orLL signifies limestone as the

second main constituent (LL signifies

high purity limestone)42,5 N: Cement strength class 42,5

Normal strength development

Portland-limestone cementPortland-limestone cement


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Portland Cement

Portland cement is CEM I

NOT

Ordinary Portland cement, OPC or

PC

BUT

CEM I


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Cement strength Classes (I)

There are three cement strength classes,based on the minimum 28 day mortar prismstrength

32,5

42,552,5

Each class can be subdivided based on earlystrength development

L: Low early strength

N: Normal strength development

R: High early strength

Note: Use of

comma ratherthan decimal point


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Cement strength Classes (II)

-52,5-2052,5 N

-52,5-3052,5 R

62,542,5-2042,5 R

62,542,5-1042,5 N

52,532,5-1032,5 R52,532,516-32,5 N

Max.

28Day

Min.

28Day

Min.

7 Day

Min.

2 Day

StrengthClass

-52,5-2052,5 N

-52,5-3052,5 R

62,542,5-2042,5 R

62,542,5-1042,5 N

52,532,5-1032,5 R52,532,516-32,5 N

Max.

28Day

Min.

28Day

Min.

7 Day

Min.

2 Day

StrengthClass

These classes apply to all CEM

cements


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Cement strength Classes (II)

-52,5-1052,5 L

62,542,516-42,5 L

52,532,512-32,5 L

Max.

28Day

Min.

28Day

Min.

7 Day

Min.

2 Day

StrengthClass

-52,5-1052,5 L

62,542,516-42,5 L

52,532,512-32,5 L

Max.

28Day

Min.

28Day

Min.

7 Day

Min.

2 Day

StrengthClass

These low early strength classes apply

only to BS EN 197- 4 CEM III cements

These low early strength classes apply

only to BS EN 197- 4 CEM III cements


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Low Heat Cement

BS EN 197-1: 2000 (inc. Amendment 1:2004)now covers some low heat cements

Low Heat is defined as a characteristic heatof hydration not exceeding 270 J/g(measured at 7 days (EN 196-8) or 41 hrs (EN196-9))

Low heat cements carry an LH suffix ie:

Example: CEM III/B 32,5N - LH


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Minor Additional Constituents (I)

BS EN 197-1 allows for the inclusion of up to 5% bymass of a minor additional constituent (or mac) in alltypes of cement

A mac is defined as: special ly selected ino rganicnatural m ineral mater ials, inorganic m ineral mater ials

derived from the cl inker product ion process o r

[speci f ied cement] cons t i tuents unless they are

[al ready] included as m ain const i tuents in the cement

Materials typically used as a mac include: Finely ground limestone

Fly Ash

Cement kiln dust (CKD)


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Minor Additional Constituents (II)

Cement containing a mac has to meet the sameperformance criteria as the same cement type andclass without a mac

Setting timeStrength

Soundness/Chemical requirements

In specification terms a CEM cement with a macis considered to be identical to the same CEM

cement without a mac

A CEM I Portland cement with 5% mac is still a

Portland cement and will perform in the same

way as a similar cement without a mac !


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Other Cements

Sulfate-resisting Portland cement: still coveredby residual British Standard BS 4027

Low early strength blastfurnace cements:

covered by British Standard BS 146:2002 (tobe withdrawn Jan 2006)

High-alumina cement: still covered by residualBritish Standard BS 915

These standards will eventually be replaced by

new European Standards, but progress on a

standard for sulfate-resisting cement is slow


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Hydration of Cement

When Portland cement is mixed with water its chemicalcompound constituents undergo a series of chemicalreactions that cause it to harden (or set).

These chemical reactions all involve the addition of water tothe basic chemical compounds. This chemical reaction withwater is called "hydration". Each one of these reactionsoccurs at a different time and rate. Together, the results ofthese reactions determine how Portland cement hardensand gains strength.

Tricalcium silicate (C3S). Hydrates and hardens rapidly andis largely responsible for initial set and earlystrength. Portland cements with higher percentages of C3Swill exhibit higher early strength.


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Hydration of Cement

Dicalcium silicate (C2S). Hydrates and hardens slowly and islargely responsible for strength increases beyond one week.

Tricalcium aluminate (C3A). Hydrates and hardensquickest. Liberates a large amount of heat almostimmediately and contributes somewhat to earlystrength. Gypsum is added to Portland cement to retard C3Ahydration. Without gypsum, C3A hydration would causePortland cement to set almost immediately after adding water.

Tetracalcium aluminoferrite (C4AF). Hydrates rapidly butcontributes very little to strength. Its use allows lower kilntemperatures in Portland cement manufacturing. MostPortland cement colour effects are due to C4AF.


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Hydration of Cement

The result of the two silicate hydrations is the

formation of a calcium silicate hydrate (often written

C-S-H because of is variable stoichiometry). C-S-H

makes up about 1/2 - 2/3 the volume of the hydratedpaste (water + cement) and therefore dominates its

behavior (Mindess and Young, 1981).


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Physical Properties of Cement

Portland cements are commonly characterized by

their physical properties for quality control

purposes. Their physical properties can be usedto classify and compare Portland cements.

The challenge in physical property

characterization is to develop physical tests that

can satisfactorily characterize key parameters.


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Keep in mind that these tests are, in general, performed on"neat" cement pastes - that is, they only include Portlandcement and water.

Neat cement pastes are typically difficult to handle and testand thus they introduce more variability into the results.

Cements may also perform differently when used in a"mortar" (cement + water + sand).

Over time, mortar tests have been found to provide a betterindication of cement quality and thus, tests on neat cementpastes are typically used only for research purposes(Mindess and Young, 1981).

However, if the sand is not carefully specified in a mortartest, the results may not be transferable.


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Fineness

Fineness, or particle size of Portland cement affects hydration rate andthus the rate of strength gain. The smaller the particle size, the greaterthe surface area-to-volume ratio, and thus, the more area available for

water-cement interaction per unit volume. The effects of greater finenesson strength are generally seen during the first seven days (PCA, 1988).

Fineness can be measured by several methods: AASHTO T 98 and ASTM C 115: Fineness of Portland Cement by the

Turbidimeter.

AASHTO T 128 and ASTM C 184: Fineness of Hydraulic Cement by the150-mm (No. 100) and 75-mm (No. 200) Sieves

AASHTO T 153 and ASTM C 204: Fineness of Hydraulic Cement by AirPermeability Apparatus

AASHTO T 192 and ASTM C 430: Fineness of Hydraulic Cement by the45-mm (No. 325) Sieve


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Soundness

When referring to Portland cement, "soundness" refers to the ability of ahardened cement paste to retain its volume after setting without delayeddestructive expansion (PCA, 1988). This destructive expansion is causedby excessive amounts of free lime (CaO) or magnesia (MgO). Most

Portland cement specifications limit magnesia content and expansion. Thetypical expansion test places a small sample of cement paste into anautoclave (a high pressure steam vessel).

The autoclave is slowly brought to 2.03 MPa (295 psi) then kept at thatpressure for 3 hours. The autoclave is then slowly brought back to roomtemperature and atmospheric pressure. The change in specimen lengthdue to its time in the autoclave is measured and reported as a

percentage. ASTM C 150, Standard Specif icat ion for Port land Cementspecifies a maximum autoclave expansion of 0.80 percent for all Portlandcement types. The standard autoclave expansion test is: AASHTO T 107 and ASTM C 151:

Autoclave Expansion of Portland Cement


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Setting Time

Cement paste setting time is affected by a number of itemsincluding: cement fineness, water-cement ratio, chemical content(especially gypsum content) and admixtures. Setting tests are used

to characterize how a particular cement paste sets. Forconstruction purposes, the initial set must not be too soon and thefinal set must not be too late. Additionally, setting times can givesome indication of whether or not a cement is undergoing normalhydration (PCA, 1988). Normally, two setting times are defined(Mindess and Young, 1981):

Init ial set. Occurs when the paste begins to stiffen considerably.

Final set. Occurs when the cement has hardened to the point atwhich it can sustain some load.


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These particular times are just arbitrary points used to

characterize cement, they do not have any fundamental

chemical significance. Both common setting time tests,

the Vicat needle and the Gillmore needle, define initialset and final set based on the time at which a needle of

particular size and weight either penetrates a cement

paste sample to a given depth or fails to penetrate a

cement paste sample. The Vicat needle test is morecommon and tends to give shorter times than the

Gillmore needle test. Table 3.14 shows ASTM C 150

specified set times.


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Test Method Set Type Time Specification

VicatInitial 45 minutes

Final 375 minutes

Gillmore Initial 60 minutesFinal 600 minutes

The standard setting time tests are:

AASHTO T 131 and ASTM C 191: Time of Setting of Hydraulic Cement

by Vicat Needle

AASHTO T 154: Time of Setting of Hydraulic Cement by GillmoreNeedles

ASTM C 266: Time of Setting of Hydraulic-Cement Paste by Gillmore

Needles


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StrengthCement paste strength is typically defined in three ways:

compressive, tensile and flexural. These strengths can be

affected by a number of items including: water-cement ratio,

cement-fine aggregate ratio, type and grading of fine

aggregate, manner of mixing and molding specimens,

curing conditions, size and shape of specimen, moisture

content at time of test, loading conditions and age (Mindess

and Young, 1981). Since cement gains strength over time,

the time at which a strength test is to be conducted must bespecified. Typically times are 1 day (for high early strength

cement), 3 days, 7 days, 28 days and 90 days (for low heat

of hydration cement). When considering cement paste

strength tests, there are two items to consider:


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Cement mortar strength is not directly related to concrete

strength. Cement paste strength is typically used as a

quality control measure.

Strength tests are done on cement mortars (cement + water +sand) and not on cement pastes.


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Comp ressive Strength

The most common strength test, compressive strength, is carried out on

a 50 mm (2-inch) cement mortar test specimen. The test specimen is

subjected to a compressive load (usually from a hydraulic machine) until

failure. This loading sequence must take no less than 20 seconds and

no more than 80 seconds. Following Table shows ASTM C 150

compressive strength specifications.

The standard cement mortar compressive strength test is:

AASHTO T 106 and ASTM C 109: Compressive Strength of HydraulicCement Mortars (Using 50-mm or 2-in. Cube Specimens)

ASTM C 349: Compressive Strength of Hydraulic Cement Mortars

(Using Portions of Prisms Broken in Flexure)


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Portland Cement TypeCuring

Time I IA II IIA III IIIA IV V

1 day - - - -12.4

(1800)

10.0

(1450)- -

3 days12.4

(1800)

10.0

(1450)

10.3

(1500)

8.3

(1200)

24.1

(3500)

19.3

(2800)-

8.3

(1200)

7 days19.3

(2800)

15.5

(2250)

17.2

(2500)

13.8

(2000)- --

6.9

(1000)

15.2

(2200)

28 days - - - - - -17.2

(2500)

20.7

(3000)

Note: Type II and IIA requirements can be lowered if either an optional heat of

hydration or chemical limit on the sum of C3S and C3A is specified


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Tens i le Streng th

Altho ugh st i l l speci f ied by ASTM, the direct tension test

does no t prov ide any useful insight into the conc rete-

making propert ies of cements. It persis ts as a specif ied

test because in the early years o f cement manufactu re,

i t used to be the mos t common test since it was di f f icul t

to f ind machines that could compress a cement sample

to failure.


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Flexural Streng th

Flexural strength (actual ly a measure of tensi le strength inbend ing ) is carr ied ou t on a 40 x 40 x 160 mm (1.57-inch x 1.57-inc hx 6.30-inch) cement mo rtar beam. The beam is then loaded at itscenter point unt i l fa i lure.

The standard cement mortar f lexu ral strength test is: ASTM C 348: Flexu ral Streng th o f Hydraul ic Cement Mor tars

Specif ic Gravi ty Test

Speci f ic gravi ty is normal ly used in mixture propor t ion ingcalculat ions. The specif ic gravi ty of Port land cement is general ly

around 3.15 whi le the specif ic gravi ty of Port land -blast-furnace-slag and Po rt land -pozzolan c ements m ay have specif ic g ravi t iesnear 2.90 (PCA, 1988).

The standard specif ic gravi ty test is:

AASHTO T 133 and ASTM C 188: Dens ity o f Hydraul ic Cement


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Heat of Hydrat ion

The heat of hydrat ion is the heat generated when water and

Port land cement react. Heat of hydrat ion is mos t inf luenced by the

propo r t ion of C3S and C3A in th e cement, but is also inf luenced by

water-cement rat io, f ineness and cu r ing temperature. As each one

of th ese factors is inc reased, heat of h ydrat ion in creases.

In large mass con crete struc tures such as gravi ty dams , hyd rat ion

heat is produced signi f icant ly faster than it can be dissipated

(especial ly in the center of large con crete masses), which can

create high temperatures in the center of these large con crete

masses that, in turn, may cause undesirable stresses as theconc rete coo ls to ambient temperature. Conversely, the heat of

hydrat ion can help maintain favorable cur ing temperatures dur ing

w in ter (PCA, 1988).

The standard heat of hy drat ion test is:

ASTM C 186: Heat of Hyd rat ion o f Hydrau l ic Cement


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Loss on Igni t ion

Loss on igni t ion is calculated by heat ing up a cement

sample to 900 - 1000C (1650 - 1830F) un ti l a cons tan t

weight is obtained. The weight loss of the samp le due to heat ing is th en

determ ined. A high loss on igni t ion can indicate pre-

hydrat ion and carbonation, wh ich may be caused by

imp roper and p rolonged storage or adul terat ion du r ing

transpo rt o r trans fer (PCA, 1988).

The standard loss on igni t ion test is con tained in:

AASHTO T 105 and ASTM C 114: Chemical Analysis of

Hydraul ic Cement


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Application of Different Types

of Cement

Portland Cement CEM I

CEM I is the cement that has been most

commonly used throughout the world incivil engineering and building works.

Concretes and mortars made using CEM

I are versatile, durable and forgiving of

poor construction practice.


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of Cement

Sulphate-Resisting Cements

SRPC is normally a low alkali cement which benefitsconcrete in resisting the alkali silica reaction (ASR).However, it is not the only sulphate-resisting cementavailable. Various factory-made composite cements arealso sulphate-resisting including the generally availableCEM II/B-V type of Portland-fly ash cement containing atleast 25% of fly ash. Such CEM II/B-V cements arepermitted for use in the same wide-range of sulphate

exposure conditions as is SRPC and are also low inreactive alkalis. Moreover, SRPC is a type of CEM Icement with a high clinker content, it is no longermanufactured in the UK and is becoming more difficult tosource. Consequently, greener sulphate-resistingcomposite cements will continue to grow in importance.


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of Cement

SRPC is used where precaution against moderate

sulphate attack is important, as in drainage structures

where sulphate concentrations in groundwater are

higher than normal but not unusually severe (Table).

Relative Degreeof Sulfate Attack

Percentage Water-SolubleSulfate (as SO4) in Soil

Samples

Sulfate (as SO4) inWater Samples,

ppm

CementType

Negligible 0.00 to 0.10 0 to 150 CEM IPositive 0.10 to 0.20 150 to 1500 SRPC

Severe 0.20 to 2.00 1500 to 10,000 CEM II/B-V

Very Severe 2.00 or more 10,000 or more CEM II/B-V


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of Cement

Rapid Hardening Portland Cements

Rapid hardening versions of CEM I cements are

available. The average particle size is smaller in these

cements and they gain strength more quickly than doordinary CEM I types. They generate more heat in the

early stages and can be useful in cold weather

concreting. However, their principal use is in

manufacturing precast concrete units where the highearly strength of the concrete permits quick re-use of

moulds and formwork.


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of Cement

White Cement

White cement is a Portland cement CEM I made

from specially selected raw materials, usuallypure chalk and white clay (kaolin) containing

very small quantities of iron oxides and

manganese oxides. White cement is frequently

chosen by architects for use in white, off-whiteor coloured concretes that will be exposed,

inside or outside buildings, to the public's gaze.


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of Cement

White Cement

White cement is a Portland cement CEM I made

from specially selected raw materials, usuallypure chalk and white clay (kaolin) containing

very small quantities of iron oxides and

manganese oxides. White cement is frequently

chosen by architects for use in white, off-whiteor coloured concretes that will be exposed,

inside or outside buildings, to the public's gaze.


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Summary

Port land cement, the chief ingredient in cement paste,

is the most w idely used bui ld ing mater ial in the wo r ld.

In the presence of water , the chemical compounds

with in Port land cement hydrate causing hardening and

strength gain.

Port land cement can be speci f ied based on i ts chem ical

compos i t ion and other var ious physical character ist ics

that affect i ts behavior.

Tests to character ize Port land cement, such as

f ineness, soundness, sett ing t ime and strength are

useful in quali ty contro l and speci f ications but should

no t be subs t i tuted for tests on PCC.


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Thank You

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