CEMENT

Finely ground powders that, when mixed with water, set to a hard mass.

Setting and hardening result from hydration, because of their hydrating properties, constructional cements, which will even set and harden under water, are often called hydraulic cements. The most important of these is PORTLAND CEMENT. 

It is a mixture of calcareous, siliceous, argillaceous and other substances. Cement is used as a binding material in mortar, concrete, etc.

Chemical compostion of Cement

Application of Cement

Grouting material

Mortar

Concrete

Manufacture of Cement

Manufacture of Cement

Crushing

Manufacture of Cement

Blending

Manufacture of Cement

Burning

Manufacture of Cement

Grinding

Types of Cement Ordinary Portland Cement

Sulfate Resisting Cement

Rapid Hardening Cement or Early

Strength Cement

Quick Setting Cement

Low Heat Cement

High Alumina Cement

Air Entraining Cement

White Cement

Ordinary Portland Cement

It is the variety of artificial cement.

It is called Portland cement because on

hardening its color resembles to rocks

near Portland in England. It was first of

all introduces in 1824 by Joseph

Aspdin, a bricklayer of Leeds, England.

Sulfate Resisting Cement

It is modified form of Ordinary Portland

Cement and is especially manufactured to resist the

sulfates.

This cement requires longer period of curing.

This cement is used for hydraulic structures in

alkaline water and for canal and water courses

lining. It develops strength slowly, but ultimately it is

as strong as Ordinary Portland Cement.

Rapid Hardening Cement

It is a high early strength cement. The

high strength at early stage is due to finer

grinding, burning at higher temperature and

increased lime content. The strength

obtained by this cement in 4 days is same

as obtained by Ordinary Portland Cement in

14 days.

Quick Setting Cement

When concrete is to be laid under water,

quick setting cement is to be used. This cement is

manufactured by adding small percentage of

aluminum sulfate which accelerates the setting

action. The setting action of such cement starts

within 5 minutes after addition of water and it

becomes stone hard in less than half an hour.

Low Heat Cement

In this cement the heat of hydration is reduced by tri calcium aluminate content. It contains less percentage of lime than an Ordinary Portland Cement. It is used for mass concrete works much as dams.

High Alumina Cement

This cement contains high aluminate

percentage usually between 35% - 55%. It

gains strength very rapidly within 24 hours. It is

also used for construction of dams and other

heavy structures. It has resistance to sulfates

and action of frost also

Air Entraining Cement

This type of cement was first of all developed in U.S.A. to

produce such concrete which would have resistance to

weathering actions and particularly to the action of frost. It is

found that entrainment of air or gas bubbles while applying

cement, increases resistance to frost action. Air entraining

cement is produced by grinding minute air entraining materials

with clinker or the materials are also added separately while

making concrete. Entrainment of air also improves workability

and durability. It is recommended that air contents should be 3%

- 4% by volume. Natural resins, fats, oils are used as air

entraining agents

White Cement

This cement is called snowcrete. As iron oxide

gives the grey color to cement, it is therefore

necessary for white cement to keep the content of

iron oxide as low as possible. Lime stone and china

clay free from iron oxide are suitable for its

manufacturing. This cement is costlier than Ordinary

Portland Cement. It is mainly used for architectural

finishing in the buildings.