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Portland Cementis the basic binding material in Portland cement concrete and as such is the most

important of the materials composing concrete.

Clinkerit is the burnt product which is mixed with 2-1/2 to 5% gypsum and pulverized to form

Portland Cement.

Hydrationis the process of chemical combination of cement and water.

Curingis the process of maintaining the water in the concrete mixture for the hydration to continue.

Also means to store specimen in a moist condition at temperature range of 10 to 240oC.

The insoluble residue test of Portland cement determines the soundness of the cement and of course

the quality of cement.

Workability of Cementis defined as the case with which fresh concrete can be handled without

segregation from the time it is mixed up to its final lacing.

Hydraulic cement

is a property of Portland cement where it combines chemically with water, then

hares for an indefinite period.

Slumpis a type of test which measure the consistency, workability an the desirable properties of

concrete.

Portland Cement Concreteis the product produced by the binding of Portland cement and aggregates

and water.

The argillaneous raw materials include clay, shale and blast furnace slag. These materials contribute

silica (SiO2), alumina (Al2O3), and iron oxide to the clinker.

The calcareous raw materials includelimestone, chalk, mark and marine shells. These materials

contribute lime (CaO) and magnesia (MgO) to the clinker.

The Tricalcium Aluminate liberates the most heat and undergoes the most shrinkage.

The dicalcium silicate hardens the slowest, but at the age of a year has about the same strength as the

tricalcium silicate.

There are five types of Portland Cement, Namely:

Type Ifor general use when the special properties of the other types are not required

Type IIfor concrete construction exposed to moderate sulphate action or where moderate heat of

hydration is required.

Type IIIFor high early strength

Type IV - for low heat hydration

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Type Vfor high sulphite resistance

The four significant compounds In the finish cement

Tricalcium silicate, Dicalcium Silicate, Tricalcium aluminate, Tetracalcium alumina-ferrite

Two desirable properties of hardened concrete while in service

Strength and durability

What is the significance of Fineness test on Portland Cement?

The significance Fineness test determine how fine the cement is, and it is necessary to choose finer

cement because finer cement will give higher strength.

What is the significance of Loss on Ignition test on Portland Cement?

The significance of loss on ignition test is to measure of how fresh the cement is and the more fresh the

cement the better the quality.

What is the significance of soundness test on Portland cement?

The significance of soundness test is to determine the absence of those qualities which tend to destroy

its strength and durability.

Asphalt

Asphalt is defined as a dark brown to black cementitious material, solid or semi-solid in consistency in

which the predominating constituents are bitumens which occur in nature as such or are obtained as

residue in refining petroleum. Asphaltu or Sphallo

Significance Properties

Consistency Fluidity or degree of hardness. It varies with temperature and with kind and amount of

the flurring agent, in the case of liquid asphalts.

Durabilityresistance to change in properties due to weathering or aging. Asphalt generally tend to

become hard and brittle with age. Good asphalt quality is more weather-resistance.

Adhesionability to adhere to aggregate in the presence of water.

Rate of Settingrate of hardening or curing. It varies with the type of flurring agent, climatic conditions

and asphalt film thickness.

DuctilityAbility to stretch without breaking.

Types of Bituminous Materials

Natural DepositsPure deposits, Rock Asphalt

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Manufacturedasphalt cement(Hot asphalt), liquid grades(slow-curing, medium curing, rapid curing

cutback, asphalt emulsions)(liquid asphalts), blown asphalts, tars

Slow curing road oil or residualis a liquid asphalt consisting of asphalt consisting of asphalt cement

and slowly volatile and non-volatile oils. It is black has the characteristic smell of oil.

Medium Curing Cutsmell of kerosene

Rapid Curing cut-black(R-C)is a readily identified by the characteristics smell of naphtha or gasoline

which is used as flux.

Emulsified Asphaltis a colloidal dispersion of asphalt in water.

Asphalt Emulsionis chocolate-colored before use, turning black when the emulsion is broken.