The document discusses cement chemistry and the key components and reactions involved. It introduces the common notation used - where elements like CaO are represented by single letters. It then explains the four main clinker phases produced by the reactions - C3S, C2S, C3A, C4AF. These correspond to the chemical compounds 3CaO·SiO2, 2CaO·SiO2, 3CaO·Al2O3, 4CaO·Al2O3·Fe2O3. It notes each phase's impact on the properties of cement such as strength, setting time, heat released.

1. Cement Chemistry
2
Chemistry and “Cement” Chemistry
Things like CaO, SiO2 are compounds, but they
combine to produce more complex compounds
Remember our shorthand - using it,
3C + S = C3S (really 3CaO.SiO2)
2C + S = C2S (2CaO.SiO2)
3C + A = C3A (3CaO.Al203)
4C + A + F = C4AF (4CaO.Al2O3.Fe2O3)

2. 3
CaO = C
SiO2 = S
Al2O3 = A
Fe2O3 = F
Na20 and K2O are Usually Combined into Total
Alkalies
MgO = M
SO3 = S
Chemistry and “Cement” Chemistry
4
Confused yet?
Chemical Notation
C
S
F
A
Cement Chemistry Notation
C
S
F
A

3. 5
Clinker Phases
C3S
C2S
C3A
C4AF
(CaO)3SiO2
(CaO)2SiO2
(CaO)3Al2O3
(CaO)4Fe2O3
Alite
Belite
Aluminate
Ferrite
6
Chemistry and “Cement” Chemistry
Alite:
3C + S = C3S
______ + ________ = 3CaO.SiO2
Belite:
2C + S = C2S
2CaO + ______ = _____________

4. 7
Chemistry and “Cement” Chemistry
Aluminate:
3C + A = C3A
______ + ________ = 3CaO.Al203
Ferrite:
4C + _____ + F = C4AF
_____+ Al2O3 + ____ = 4CaO.Al2O3.Fe2O3
8
Clinker Phases
“Phases” are impure compounds
____ is called “Alite”
C2S is called “_____”
____ is called the “Aluminate Phase”
C4AF is called the “______ Phase”

5. 9
Impact of the phases
Clinker phase ‘Ideal’ content [%] Main effect on
C3S 60 - 65
Early strength
Final strength
C2S 15 - 5 Final strength
C3A 7 - 10
Setting and water demand
Heat of Hydration
C4AF 8 - 10 Color
Affects C3A (Iron Content)