Chapter 2:

Blended Cement and other

types of cement
Oldest Concrete Found To
Date

 dates around 7000 BC

— a lime concrete floor found during the construction

of a road at Yiftah El in Galilee, Israel.
Beginning of the Industry

 Portland cement was first patented in 1824

 Named after the natural limestone quarried on
the Isle of Portland in the English Channel
Portland Cement First
Produced
 North America
1871— Coplay, Pennsylvania

 Canada
1889 — Hull, Quebec
Primary Components of Raw
Materials Necessary for
Portland Cement Manufacture
 Calcium
 Silica
 Alumina
 Iron
Calcium Iron Silica Alumina Sulfate
Alkali waste Blast-furnace Calcium silicate Aluminum-ore Anhydrite
Aragonite flue dust Cement rock refuse Calcium
Calcite Clay Clay Bauxite sulfate
Cement-kiln Iron ore Fly ash Cement rock Gypsum
dust Mill scale Fuller’s earth Clay
Cement rock Ore washings Limestone Copper slag
Chalk Pyrite cinders Loess Fly ash
Clay Shale Marl Fuller’s earth
Fuller’s earth Ore washings Granodiorite
Limestone Quartzite Limestone
Marble Rice-hull ash Loess
Marl Sand Ore washings
Seashells Sandstone Shale
Shale Shale Slag
Slag Slag Staurolite
Traprock
Quarry
Traditional Manufacture of Portland
Cement

1. Stone is first reduced to 125 mm

(5 in.) size, then to 20 mm (3/4 in.),
and stored.
2. Raw materials are ground to powder and blended.

or
2. Raw materials are ground, mixed with water to form slurry,
and blended.
3. Burning changes raw mix chemically into cement clinker.
4. Clinker with gypsum is ground into portland cement and
shipped.
Dry Process Manufacture
of Portland Cement

1. Stone is first reduced to 125 mm

(5 in.) size, then to 20 mm (3/4 in.),
and stored.
2. Raw materials are ground,
to powder and blended.
3. Burning changes raw mix chemically into clinker. Note
four stage preheater, flash furnaces, and shorter kiln.
4. Clinker with gypsum is ground into portland cement and
shipped
Clinker
Gypsum
Process of Clinker Production

(1)
(2)
(3)
Portland Cement

By definition —
a hydraulic cement produced by pulverizing
clinker consisting essentially of hydraulic
calcium silicates, usually containing one or
more of the forms of calcium sulfate as an
interground addition.
Types of Portland Cement

ASTM C 150 (AASHTO M 85)

I Normal
IA Normal, air-entraining
II Moderate sulfate resistance
IIA Moderate sulfate resistance, air-
entraining
III High early strength
IIIA High early strength, air-entraining
IV Low heat of hydration
V High sulfate resistance
Performance of Concretes
Made with Different Cements
in Sulfate Soil
Performance of Concretes
Made with Different W/C-Ratios
in Sulfate Soil
Type II & Type V
Sulfate Resistant
Cements
 Outdoor Sulfate Test

Type V Cement Type V Cement

W/C-ratio = 0.65 W/C-ratio = 0.39
Moderate and Low Heat
Cements
Type III
High Early
Strength
Cements
White Portland
Cement
Blended Hydraulic Cement
ASTM C 595
General —
a hydraulic cement consisting of two or more
inorganic constituents, which contribute to the
strength gaining properties of cement.
Blended Cements

 Clinker
 Gypsum
 Portland cement
 Fly ash
 Slag
 Silica Fume
 Calcined Clay
Blended Hydraulic Cements

ASTM C 595 (AASHTO M 240)

Type IS Portland blast-furnace
slag cement
Type IP Portland-pozzolan
cement
Type P Portland-pozzolan
cement
Type I(PM) Pozzolan-modified
portland cement
Type S Slag cement
Type I(SM) Slag-modified portland
cement
 Hydraulic Cements
ASTM C 1157
 First performance specification for hydraulic
cements
 Cements meet physical performance test
requirements rather than prescriptive
restrictions on ingredients or cement chemistry
as in other cement specifications.
 Provides for six types
Hydraulic Cement

ASTM C 1157
Type GU General use
Type HE High early strength
Type MS Moderate sulfate resistance
Type HS High sulfate resistance
Type MH Moderate heat of hydration
Type LH Low heat of hydration
 Cement Applications
Resistance
to
Moderate High Low heat Moderate High alkali-silica
Cement General heat of early of sulfate sulfate reactivity
specification purpose hydration strength hydration resistance resistance (ASR)

ASTM C 150 II
(AASHTO M 85) (moderate Low alkali
I III IV II V
portland heat option
cements option)

ASTM C 595 IS IS(MS)

IS(MH)
(AASHTO M 240) IP IP(MS) Low
IP(MH)
blended I(PM) P(LH) P(MS) reactivity
I(PM)(MH)
hydraulic I(SM) I(PM)(MS) option
I(SM)(MH)
cements S, P I(SM)(MS)

ASTM C 1157
hydraulic GU MH HE LH MS HS Option R
cements
 Special cements Type Application
White portland cements, I, II, III, V White or colored concrete, masonry,
ASTM C 150 mortar, grout, plaster, and stucco
White masonry cements, M, S, N White mortar between masonry
ASTM C 91 units
Masonry cements, ASTM C M, S, N Mortar between masonry units,
91 plaster, and stucco
Mortar cements, ASTM C M, S, N Mortar between masonry units
1329
Plastic cements, ASTM C M, S Plaster and stucco
1328
Expansive cements, ASTM E-1(K), E-1(M), E-1(S) Shrinkage compensating concrete
C 845
Oil-well cements, API-10 A, B, C, D, E, F, G, H Grouting wells
Water-repellent cements Tile grout, paint, and stucco finish
coats
Regulated-set cements Early strength and repair
 Special cements Type Application
Cements with functional General concrete construction
additions, needing special characteristics such
as; water-reducing, retarding, air
ASTM C 595 (AASHTO M 240), entraining, set control, and
ASTM C 1157 accelerating properties
Finely ground (ultrafine)
Geotechnical grouting
cement
Repair, chemical resistance and high
Calcium aluminate cement
temperature exposures
Magnesium phosphate
Repair and chemical resistance
cement
General construction, repair, waste
Geopolymer cement
stabilization
Ettringite cements Waste stabilization
Sulfur cements Repair and chemical resistance
General paving where very rapid
Rapid hardening hydraulic
VH, MR, GC (about 4 hours) strength development
cement
is required
Masonry Cements

Type N — for Type O and Type N mortars and

with portland cement for mortar
Types S and M

Type S — for Type S mortar

Type M — for Type M mortar

Stucco using Masonry or Plastic
Cements
Finely-Ground Cements

Grout penetration
in soil
Expansive Cement Concrete
Drinking Water Applications
Chemical Compounds of
Portland Cement
Hydration Products
 Portland Cement Compound Hydration Reactions (Oxide Notation)
2 (3CaO•SiO2) + 11 H2O = 3CaO•2SiO2•8H2O + 3 (CaO•H2O)
Tricalcium silicate Water Calcium silicate Calcium hydroxide
hydrate (C-S-H)
2 (2CaO•SiO2) + 9 H2O = 3CaO•2SiO2•8H2O + CaO•H2O
Dicalcium silicate Water Calcium silicate Calcium hydroxide
hydrate (C-S-H)
3CaO•Al2O3 + 3 (CaO•SO3•2H2O) + 26 H2O = 6CaO•Al2O3•3SO3•32H2O
Tricalcium Gypsum Water Ettringite
aluminate
2 (3CaO•Al2O3) + 6CaO•Al2O3•3SO3•32H2O + 4 H2O = 3 (4CaO•Al2O3•SO3•12H2O)
Tricalcium Ettringite Water Calcium
aluminate monosulfoaluminate
3CaO•Al2O3 + CaO•H2O + 12 H2O = 4CaO•Al2O3•13H2O
Tricalcium Calcium hydroxide Water Tetracalcium aluminate
aluminate hydrate

4CaO• Al2O3•Fe2O3 + 10 H2O + 2 (CaO•H2O) = 6CaO•Al2O3•Fe2O3•12H2O

Tetracalcium Water Calcium Calcium aluminoferrite
aluminoferrite hydroxide hydrate
SEMs of Hardened
Cement Paste
 Chemical composition, %
Type of
portland
cement SiO2 Al2O3 Fe2O3 CaO MgO SO3 Na2Oeq

I (mean) 20.5 5.4 2.6 63.9 2.1 3.0 0.61

II (mean) 21.2 4.6 3.5 63.8 2.1 2.7 0.51

III (mean) 20.6 4.9 2.8 63.4 2.2 3.5 0.56

IV (mean) 22.2 4.6 5.0 62.5 1.9 2.2 0.36

V (mean) 21.9 3.9 4.2 63.8 2.2 2.3 0.48

White (mean) 22.7 4.1 0.3 66.7 0.9 2.7 0.18

 Potential compound composition,%
Type of Blaine
portland fineness
cement C3 S C2 S C3 A C4AF m2/kg

I (mean) 54 18 10 8 369

II (mean) 55 19 6 11 377

III (mean) 55 17 9 8 548

IV (mean) 42 32 4 15 340

V (mean) 54 22 4 13 373

White (mean) 63 18 10 1 482

Reactivity of Cement Compounds
Nonevaporable Water Contents

Nonevaporable
Hydrated cement (combined) water content
compound (g water/g cement compound)
C3S hydrate 0.24
C2S hydrate 0.21
C3A hydrate 0.40
C4AF hydrate 0.37
Free lime (CaO) 0.33
Scanning-Electron Micrograph
of Powdered Cement
Fineness of Cement

ASTM C 204

ASTM C 115
Cement Fineness
Particle Size Distribution
Soundness Test

ASTM C 151
(AASHTO T 107 )
Consistency of Cement
Paste
ASTM C 187
(AASHTO T 129)

Vicat plunger
Consistency of
Mortar
ASTM C 230
(AASHTO M 152)
and ASTM C 1437

Flow table
Setting Time
ASTM C 191
(AASHTO M 131)

Vicat apparatus
Setting Time
ASTM C 266
(AASHTO M 154)

Gillmore needle
Setting Times for Portland
Cements
Mortar Cubes
ASTM C 109
(AASHTO T 106)
Strength Development of
Mortar Cubes
Strength Development
Type I and II Cements
Strength Development
Type III, IV, and V Cements
 Heat of Hydration at 7 Days

Type I Type II Type II Type III Type Type V

cement cement Moderate cement IV cement
heat cement cement
% of
100 99 75 106 67 89
Type I
Heat Evolution
Density of Cement
Le Chatelier flask ( ASTM C 188 or
AASHTO T 133)

Helium
pycnometer
Bulk Density

Bulk density of cement

varies between
830 kg/m3 (52 lb/ft3)
and

1650 kg/m3 (103 lb/ft3).

Thermal Analysis
 Thermogravimetric analysis (TGA)
 Differential Thermal Analysis
(DTA)
 Differential Scanning Calorimetry
(DSC)
Differential Scanning Calorimetry
Thermogram of a Cement Paste after
(a) 15 min and (b) 24 h of Hydration
Virtual Cement Testing
Transporting Cement
Packaging and Storage
 POZZOLANS
(Supplementary Cementitious Materials)
Pozzolan

 The name Pozzolan comes from the town

Pozzuoli, Italy.
 Ancient Romans (~100 B.C.) produced a hydraulic
binder by mixing hydrated lime with soil
(predominantly volcanic ash)
 Horasan mortar, mixing lime with finely divided
burned clay, is extensively used by Ottomans
 Nowadays, the word pozzolan covers a broad
range of natural and artificial materials.
Pozzolan

a material that, when used in conjunction with portland cement,

contributes to the properties of the hardened concrete through hydraulic
or pozzolanic activity, or both.
 Natural (Volcanic ash, volcanic tuff, pumicite)
 Artificial (fly ash, silica-fume, granulated blast furnace slag)
Pozzolan

 Siliceous or aluminous material, which in itself possesses little or no

cementitious value but will, in finely divided form and in the presence of
moisture, chemically react with calcium hydroxide Ca(OH)2 to form
compounds possessing hydraulic cementitious properties.
 POZZOLANS

Iron oxide, calcium oxide,

Silica&Alumina magnesium oxide,
(higher amounts) alkalies
(lesser amounts)

POZZOLANIC REACTIONS
Calcium Hydroxide+Silica+Water → “Calcium-Silicate-Hydrate”
(C-S-H)
C-S-H provides the hydraulic binding property of the material.

Pozzolanic Activity: Capacity of pozzolan to form alumino-

silicates with lime to form cementitious products. (How good
how effective the pozzolan is!)
FACTORS THAT AFFECT THE
ACTIVITY OF POZZOLANS
1) SiO2 + Al2O3 + Fe2O3 content

2) The degree of amourpheness of its structure

3) Fineness of its particles

 1) SiO2 + Al2O3 + Fe2O3
 The greater amount of these, the greater its
activity.
 ASTM C 618 & TS 25 → min “SiO2+Al2O3+Fe2O3” for
natural pozzolans > 70%
 Fly Ash - ASTM
✓ Class C→ from lignitide or subbituminous coals
(SiO2+Al2O3+Fe2O3>50%)
✓ Class F→ from bituminous coals and
SiO2+Al2O3+Fe2O3>70%
 Silica fume → SiO2 ≈ 85-98%
 Blast Furnace Slag→ SiO2 ~ 30-40%
Al2O3 ~ 7-19%
CaO ~ 30-50%
 2) Amorphousness

 For chemical reaction → pozzolans must be amorphous

 Volcanic ash, volcanic tuff, fly ash, silica fume are all amorphous by nature.
 Clays → contain high amounts of silica & alumina but have a crystallic structure!
(Do not possess pozzolanic activity)

 However, by heat treatment, such as calcining

~700-900°C crystallic structure is destroyed & a
quasi-amorphous structure is obtained.
2) Amorphousness
➢ Clay → does not possess pozzolanic property
➢ Burned clay → possess pozzolanic property
➢ Blast furnace slag → contain high amounts of silica, alumina & lime.
➢ However, if molten slag is allowed to cool in air, it gains a crystal structure. * do
not possess pozzolanic property.
➢ However, if it is cooled very rapidly by pouring it into water, it becomes a granular
material & gains amorpousness. * possess pozzolanic property.
 3) Fineness
➢ Pozzolanic activity increases as fineness increases.

➢ Volcanic ash, rice husk ash, fly ash, condensed silica fume are obtained in
finely divided form.

➢ Volcanic tuff, granulated blast furnace slag & burned clay must be ground.
 DETERMINATION OF POZZOLANIC
ACTIVITY
➢ Pozzolanic activity is determined by “strength activity indexes”

➢ Six mortar cubes are prepared (ASTM)

→”Control Mixture” 500 g portland cement+1375 g sand+242 ml water
→”Test Mixture” 400g of portland cement+100g of pozzolan+1375g of sand+some
water for the same consistency
➢ Compressive testing at 7 or 28 days

➢ Strength Activity Index (SAI) =A/B*100

➢ A=f’c of test mixture

➢ B=f’c of control mixture

➢ ASTM C 618 → SAI ≥ 75%

 CHEMICAL COMPOSITION OF
POZZOLANS
➢ Silica Fume is mostly SiO2

➢ G. G. Blast Furnace Slag→ high amounts of CaO (self-cementitious)

➢ Class C Fly Ash has CaO (self-cementitious)

 Chemical Analysis of Typical Fly Ash, Slag, Silica Fume,
Calcined Clay, Calcined Shale, and Metakaolin
Artificial Pozzolans Natural Pozzolans
Class F Class C Silica Calcined Calcined Meta-
fly ash fly ash Groundslag fume clay shale kaolin
SiO2, % 52 35 35 90 58 50 53

Al2O3, % 23 18 12 0.4 29 20 43

Fe2O3, % 11 6 1 0.4 4 8 0.5

CaO, % 5 21 40 1.6 1 8 0.1

SO3, % 0.8 4.1 9 0.4 0.5 0.4 0.1

Na2O, % 1.0 5.8 0.3 0.5 0.2 — 0.05

K2O, % 2.0 0.7 0.4 2.2 2 — 0.4

Total Na
2.2 6.3 0.6 1.9 1.5 — 0.3
eq. alk, %
SILICA FUME FLY ASH

GRANULATED BLAST FURNACE SLAG

 Selected Properties of Typical Fly Ash, Slag, Silica Fume,
Calcined Clay, Calcined Shale, and Metakaolin

Class F Class C Groun Silica Calcined Calcined Meta-

fly ash fly ash dslag fume clay shale kaolin

Loss on ignition,
2.8 0.5 1.0 3.0 1.5 3.0 0.7
%

Blaine fineness,
420 420 400 20,000 990 730 19,000
m2/kg

Relative density 2.38 2.65 2.94 2.40 2.50 2.63 2.50

Typical Amounts of Pozzolans in Concrete
by Mass of Cementing Materials

 Fly ash
 Class C 15% to 40%
 Class F 15% to 20%
 Slag 30% to 45%
 Silica fume 5% to 10%
 Calcined clay 15% to 35%
 Metakaolin 10%
 Calcined shale 15% to 35%
 REQUIREMENTS FOR AN ACCEPTABLE
QUALITY OF POZZOLAN

➢ TS 25 → Natural Pozzolans
➢ TS 639 → Fly Ash
➢ ASTM C 618 → For Natural Pozzolan & Fly Ash

Natural Class F Class C

Fineness (max. % retained
when wet sieved on 45 mm
sieve) 34% 34% 34%
Strength Activity Index 75 75 75
min "SiO2+Al2O3+Fe2O3" 70 70 50
USES OF POZZOLANS
1) Direct use of Pozzolan by Mixing it with Calcium
Hydroxide
Extensively used in ancient times but not very
common now.
2) Use of Pozzolan in Producing Blended Cements
Grinding “Clinker+Pozzolan+Gypsum”→
Portland Pozzolan Cements Extensively used
3) Use of Pozzolan as an Admixture
“Cement+Pozzolan+Aggregate+Water”→
Concrete
 POZZOLANS
(Supplementary Cementitious Materials)
Pozzolan

 The name Pozzolan comes from the town

Pozzuoli, Italy.
 Ancient Romans (~100 B.C.) produced a hydraulic
binder by mixing hydrated lime with soil
(predominantly volcanic ash)
 Horasan mortar, mixing lime with finely divided
burned clay, is extensively used by Ottomans
 Nowadays, the word pozzolan covers a broad
range of natural and artificial materials.
Pozzolan

a material that, when used in conjunction with portland cement,

contributes to the properties of the hardened concrete through hydraulic
or pozzolanic activity, or both.
 Natural (Volcanic ash, volcanic tuff, pumicite)
 Artificial (fly ash, silica-fume, granulated blast furnace slag)
Pozzolan

 Siliceous or aluminous material, which in itself possesses little or no

cementitious value but will, in finely divided form and in the presence of
moisture, chemically react with calcium hydroxide Ca(OH)2 to form
compounds possessing hydraulic cementitious properties.
 POZZOLANS

Iron oxide, calcium oxide,

Silica&Alumina magnesium oxide,
(higher amounts) alkalies
(lesser amounts)

POZZOLANIC REACTIONS
Calcium Hydroxide+Silica+Water → “Calcium-Silicate-Hydrate”
(C-S-H)
C-S-H provides the hydraulic binding property of the material.

Pozzolanic Activity: Capacity of pozzolan to form alumino-

silicates with lime to form cementitious products. (How good
how effective the pozzolan is!)
FACTORS THAT AFFECT THE
ACTIVITY OF POZZOLANS
1) SiO2 + Al2O3 + Fe2O3 content

2) The degree of amourpheness of its structure

3) Fineness of its particles

 1) SiO2 + Al2O3 + Fe2O3
 The greater amount of these, the greater its
activity.
 ASTM C 618 & TS 25 → min “SiO2+Al2O3+Fe2O3” for
natural pozzolans > 70%
 Fly Ash - ASTM
✓ Class C→ from lignitide or subbituminous coals
(SiO2+Al2O3+Fe2O3>50%)
✓ Class F→ from bituminous coals and
SiO2+Al2O3+Fe2O3>70%
 Silica fume → SiO2 ≈ 85-98%
 Blast Furnace Slag→ SiO2 ~ 30-40%
Al2O3 ~ 7-19%
CaO ~ 30-50%
 2) Amorphousness

 For chemical reaction → pozzolans must be amorphous

 Volcanic ash, volcanic tuff, fly ash, silica fume are all amorphous by nature.
 Clays → contain high amounts of silica & alumina but have a crystallic structure!
(Do not possess pozzolanic activity)

 However, by heat treatment, such as calcining

~700-900°C crystallic structure is destroyed & a
quasi-amorphous structure is obtained.
2) Amorphousness
➢ Clay → does not possess pozzolanic property
➢ Burned clay → possess pozzolanic property
➢ Blast furnace slag → contain high amounts of silica, alumina & lime.
➢ However, if molten slag is allowed to cool in air, it gains a crystal structure. * do
not possess pozzolanic property.
➢ However, if it is cooled very rapidly by pouring it into water, it becomes a granular
material & gains amorpousness. * possess pozzolanic property.
 3) Fineness
➢ Pozzolanic activity increases as fineness increases.

➢ Volcanic ash, rice husk ash, fly ash, condensed silica fume are obtained in
finely divided form.

➢ Volcanic tuff, granulated blast furnace slag & burned clay must be ground.
 DETERMINATION OF POZZOLANIC
ACTIVITY
➢ Pozzolanic activity is determined by “strength activity indexes”

➢ Six mortar cubes are prepared (ASTM)

→”Control Mixture” 500 g portland cement+1375 g sand+242 ml water
→”Test Mixture” 400g of portland cement+100g of pozzolan+1375g of sand+some
water for the same consistency
➢ Compressive testing at 7 or 28 days

➢ Strength Activity Index (SAI) =A/B*100

➢ A=f’c of test mixture

➢ B=f’c of control mixture

➢ ASTM C 618 → SAI ≥ 75%

 CHEMICAL COMPOSITION OF
POZZOLANS
➢ Silica Fume is mostly SiO2

➢ G. G. Blast Furnace Slag→ high amounts of CaO (self-cementitious)

➢ Class C Fly Ash has CaO (self-cementitious)

 Chemical Analysis of Typical Fly Ash, Slag, Silica Fume,
Calcined Clay, Calcined Shale, and Metakaolin
Artificial Pozzolans Natural Pozzolans
Class F Class C Silica Calcined Calcined Meta-
fly ash fly ash Groundslag fume clay shale kaolin
SiO2, % 52 35 35 90 58 50 53

Al2O3, % 23 18 12 0.4 29 20 43

Fe2O3, % 11 6 1 0.4 4 8 0.5

CaO, % 5 21 40 1.6 1 8 0.1

SO3, % 0.8 4.1 9 0.4 0.5 0.4 0.1

Na2O, % 1.0 5.8 0.3 0.5 0.2 — 0.05

K2O, % 2.0 0.7 0.4 2.2 2 — 0.4

Total Na
2.2 6.3 0.6 1.9 1.5 — 0.3
eq. alk, %
SILICA FUME FLY ASH

GRANULATED BLAST FURNACE SLAG

 Selected Properties of Typical Fly Ash, Slag, Silica Fume,
Calcined Clay, Calcined Shale, and Metakaolin

Class F Class C Groun Silica Calcined Calcined Meta-

fly ash fly ash dslag fume clay shale kaolin

Loss on ignition,
2.8 0.5 1.0 3.0 1.5 3.0 0.7
%

Blaine fineness,
420 420 400 20,000 990 730 19,000
m2/kg

Relative density 2.38 2.65 2.94 2.40 2.50 2.63 2.50

Typical Amounts of Pozzolans in Concrete
by Mass of Cementing Materials

 Fly ash
 Class C 15% to 40%
 Class F 15% to 20%
 Slag 30% to 45%
 Silica fume 5% to 10%
 Calcined clay 15% to 35%
 Metakaolin 10%
 Calcined shale 15% to 35%
 REQUIREMENTS FOR AN ACCEPTABLE
QUALITY OF POZZOLAN

➢ TS 25 → Natural Pozzolans
➢ TS 639 → Fly Ash
➢ ASTM C 618 → For Natural Pozzolan & Fly Ash

Natural Class F Class C

Fineness (max. % retained
when wet sieved on 45 mm
sieve) 34% 34% 34%
Strength Activity Index 75 75 75
min "SiO2+Al2O3+Fe2O3" 70 70 50
USES OF POZZOLANS
1) Direct use of Pozzolan by Mixing it with Calcium
Hydroxide
Extensively used in ancient times but not very
common now.
2) Use of Pozzolan in Producing Blended Cements
Grinding “Clinker+Pozzolan+Gypsum”→
Portland Pozzolan Cements Extensively used
3) Use of Pozzolan as an Admixture
“Cement+Pozzolan+Aggregate+Water”→
Concrete