Ordinary Portland Cement

Ordinary Portland Cement (OPC) the most widely and commonly used cement in the world. This type of cement is manufactured to powder by mixing limestone and other raw materials which consist of argillaceous, calcareous and gypsum. It is preferred in places where there is need of fast construction. This cement is available in the market in three grades namely OPC 33, OPC 43 and OPC 53.These grades imply the maximum strength of the particular cement after 28 days.

Properties of Various Grades of Ordinary Portland Cement

Indian Standard Codes

Grade

33 Grade

43 Grade

53 Grade

Properties

Chemical Properties

Ratio of percentage of lime to percentages of silica, alumina and iron oxide

Not greater than 1.02 and not less than 0.66

Not greater than 1.02 and not less than 0.66

Not greater than 1.02 and not less than 0.8

Ratio of percentage of alumina to percentage of iron oxide

Not less than 0.66

Not less than 0.66

Not less than 0.66

Insoluble residue, percent by mass

Not more than 4

Not more than 2

Not more than 2

Magnesia, percent by mass

Not more than 6

Not more than 6

Not more than 6

Total Sulphur content calculated as Sulphuric anhydride (SO2), percent by mass

(a) When tricalcium aluminate is less than or equal to 5

Not more than 2.5

Not more than 2.5

Not more than 2.5

(b) When tricalcium aluminate is greater than 5

Not more than 3

Not more than 3

Not more than 3

Total loss on ignition, percent by mass, Max

Not more than 5 %

Not more than 5 %

Not more than 5 %

Chloride content, percent by mass, Max

Not more than 0.1 %

Not more than 0.1 %

Not more than 0.1 %

Alkali content

Not more than 0.05

Not more than 0.05

Not more than 0.05

Physical Properties

Setting Time

3 days

7 Days

28 Days

3 days

7 Days

28 Days

3 days

7 Days

28 Days

Avg. Compressive Strength in N/mm^2

16

22

33

23

33

43

27

37

53

Fineness in m^2 /kg, Min.

225

225

225

Soundness

a) By Le Chatelier method, mm, Max

10

10

10

b) By autoclave test method, percent, Max

0.8

0.8

0.8

Setting time

a) Initial in minutes, Min

30

30

30

b) Final in minutes, Max

600

600

600

Other Information

Code Reference

IS Code – IS 269 : 1989

IS Code – IS 8112: 1989

IS Code – IS 12269 : 1987

European Standard – EN-197-1

Types

Class 32.5

Class 42.5

Class 52.5

Properties

Compressive Strength in MPa

   

2 Days

10

20

20 -30

7 Days

Greater than 16

  

28 Days

32.5 -52.5

42.5 – 62.5

Greater than  52.5

Initial Setting Time

Greater than 75

Greater than 60

Greater than 45

Soundness

10mm

10mm

10mm