PRESENTATION ON CEMENTS

....MADE BY….

HARSH PALIWAL

Roll no.:- 13/IEC/013

MANIK GUPTA

Roll no.:- 13/IEC/017

Uses of Portland Cement Concrete

BuildingsBridgesPavementsConcrete block buildings

Other Uses of Cementitious Materials

Mortar for masonryGrout (protection, leveling, bonding, ...)ShotcreteCement boardSoil StabilizationRailroad ties, countertops, moldings...

Portland Cement History

Egyptian Pyramid of Cheops (3000 B.C.) First Calcareous Cement (CaO based)

Calcined gypsum

Roman and Greek ProjectsFirst Hydraulic Cements (100 B.C.) calcined limestone and clay

History of Cement2000 B.C.: Egyptians used cement in mortar when making Pyramids27 B.C.: Roman cement made of lime

and volcanic ash1756: Smeaton rebuilt Eddystone Lighthouse1824: Joseph Aspdin discovered and patented “Portland” cement

Isle of Portland Quarry Stone next to a Cylinder of Modern Concrete

Portland Cement History

Rotary Kiln Ransome (1886), Edison (1909)

Gypsum and Air-Entraining Admixtures

U.S. (1910-1940)

Cement is a Manufactured Material

Go Animation

Common Sources for Raw Materials

Lime (CaO)- Limestone, shale

Silica (SiO2) -Clay, sand, shale

Alumina (Al2O3)

- Clay, fly ash, shaleIron (Fe2O3)

- Clay, iron ore

Portland Cement Production

5/8 CaOLimestone or calcareous rock 1/5 SiO2 Clay or argillaceous rock1/10 Al2O3 Clay or Ore

1/20 Fe2O3 Clay or Ore

1/20 CaSO4*2H2O Gypsum

Cement Clinker

Shorthand Chemistry

C = CaO H = H2O

S = SiO2 S = SO3

A = Al2O3 F = Fe2O3

Clinker: artificial mineral containing:

C3S tricalcium silicate

C2S dicalcium silicate

C3A tricalcium aluminate

C4AF tetracalcium aluminoferrite

Clinker Micrographs

Finish GrindingInterground with ~5% Gypsum95% material must pass #325 Sieve

Hydration of Portland Cement

C3SH4 Calcium Silicate Hydrate

CH Calcium Hydroxide

Hydration of Portland Cement

C6AS3H32 Ettringite stable in SO4

-2 solution from C3A+CSH2

C4ASH12 Monosulfate unstable in SO4

-2

From C6AS3H32 +C3A

C3(A,F)H6 Hydrogarnets

Portland Cement Properties

Hydraulic Fineness 90% finer than 45m

Setting Time Controlled False Set Flash Set

Portland Cement Properties

Soundness MgO or Hard-Burned Lime

Specific Gravity: 3.15Heat of Hydration - Exothermic Reaction C3S & C3A

LOI SO3

How are Portland Cements different?Four Main Compounds

Tricalcium Silicate (C3S)

Dicalcium Silicate (C2S)

Tricalcium Aluminate (C3A)

Tetracalcium Aluminoferrite (C4AF)

Supplementary Cementing Materials

DEFINITION: Powdered or pulverized materials added before or during mixing to improve or change some of the plastic or hardened properties of concrete.

•Cementitious Cementitious •PozzolanPozzolans s •Nominally InertNominally Inert

Cementitious Materials

Possess hydraulic cementing propertiesGGBF slag (by-product of steel industry)Natural cement- Cement RockHydraulic hydrated lime

Fly AshClass F (low calcium) - from burning anthracite or bituminous coal, is pozzolanicClass C - from burning sub-bituminous or lignite coal, is somewhat cementitious

Types of Cement (ASTM C150 or AASHTO M85)

Type I Normal*Type II Moderate Heat and Sulfate*Type III High-Early Strength*Type IV Low Heat of HydrationType V High Sulfate Resistance

Special Types of Cement

Type IP Blended with a Pozzolan*Type IS Blended with a SlagType I-II Meets Type I and II standards*White Type I or III without Fe Masonry Blended Cements with Lime*Type K Expansive and ShrinkageOil Well Slow-set, high temp. & press.

The Water - Cement Ratio Law

For given materials the strength of the concrete (so long For given materials the strength of the concrete (so long as we have a plastic mix) depends solely on the relative as we have a plastic mix) depends solely on the relative quantity of water as compared with the cement, quantity of water as compared with the cement, regardless of mix or size and grading of aggregate.regardless of mix or size and grading of aggregate.

Duff A. AbramsDuff A. Abrams

May 1918May 1918

Same cement content

w/cm ratio

10152025303540455055

0.25

0.35

0.45

0.55

0.65

w/cm ratio

Fc'

, M

Pa

350kg300kg250kg

WCM

W

WWater

CementitiousMaterial