Portland cement (PC) - a fine powder which is produced by heating limestone and clay minerals during a kiln and forms clinker. The clinker is grinded to fine powder with addition of bit of other materials. It is the foremost commonly used sorts of cement within the world. It is used as basic ingredients of concrete, mortar, stucco etc. It is named as hydraulic cement due to its similarity to Portland stone which was found on the Isle of Portland in Dorset, England.

Ordinary hydraulic cement (OPC) is graded consistent with their strength. The grade indicates the compression strength (mpa) of the concrete which will attain after 28 days of setting.

It is invented by the Joseph Aspdin in 1824. But the credit for the invention of the new hydraulic cement goes to his son William Aspdin in 1840’s.

Portland cement is that the commonest sort of cement generally use round the world as a basic ingredient of concrete, mortar, stucco, and non-specialty grout.

 

Different grades of cement


53 grade cement

Compression strength:

Cement grade indicates the compressive strength of cement concrete after 28 days of setting. The 53 grade cement achieves a compressive strength of 53 MPa (Mega Pascal) in 28 days of setting.

Uses and applications:

53 grade OPC is often used for later applications:

RCC works (preferably where the grade of concrete is M-25 and above).

Concrete -prestressed components

Prefabricated concrete items such as paving blocks, tiles building blocks etc.

Runways, concrete roads, bridges etc.

Initial strength:

53 grade cement is used for rapid construction, so that  initial strength can  be achieved quickly. 53 grade cement has a faster setting compared to 43 grade cement.

The 53 grade achieves 27 MPa in 3 days, 37 MPa in 7 days.

IS Code:

IS 12269: 1987 (reaffirmed 2008) "Specification for 53 grade ordinary hydraulic cement."


43 grade cement

Compression strength:

Cement grade indicates the compressive strength of cement concrete after 28 days of setting. The 43 grade cement achieves a compressive strength of 43 MPa (mega pascal) in a 28-day of setting period compared to the 53 MPa achieved by the 53 grade cement

Uses and applications:

43 grade OPC cement is commonly used for plastering works, non-RCC structures, paths, etc. where the initial setting time is not valued.

The 43 grade OPC is often used for the following applications:

General civil engineering construction work.

Asbestos products such as sheets and pipes.

RCC works (preferably where the grade of concrete is up to M-30).

Non-structural works such as plastering, flooring etc.

Precast items such as blocks, tiles, pipes, etc.

Initial strength:

The 43 grade achieves 23 MPa in 3 days, 33 MPa in 7 days.

IS Code:

IS 8122: 1989 ( reaffirmed 2005) "Specification for 43 grade ordinary hydraulic cement."


33 grade cement

Compression strength:

Cement grade indicates the compressive strength of cement concrete after 28 days of setting. The 33 grade cement achieves a compressive strength of 33 MPa (Mega Pascal) in 28 days of setting.

Uses and applications:

This cement is used for general civil construction work under normal environmental conditions. It can be used for plastering and single storey individual houses.

Due to low compressive strength, this cement is not commonly used where high grade of concrete i.e. M-20 and above is required. The availability of upper grades of OPCs within the market is affecting the use of 33 grades of OPCs and now 43 grades of OPCs a day are used for general construction work instead of 33 grades of OPCs.

Initial strength:

The 33 grade achieves 16 MPa in 3 days, 22 MPa in 7 days.

IS Code:

IS 269: Specification for ordinary hydraulic cement, 33 grades.

Variety of brands of cement: -

Birla Cement, Zuari Cement, Koramandal Cement, Ultratech Cement, ACC Cement, Ramco Cement, Dalmia Cement are several documented brands in Southern India.









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