Ordinary Portland Cement
Nearly 60% of the Cement used in the country is Ordinary Portland Cement. It is most suitable for use in general concrete construction where there is no exposure to Sulphates in the soil or in ground water. It has a medium rate of strength development and heat generation. It's also known as Normal Setting Cement.
The Bureau of Indian Standards ( BIS ) has graded the Ordinary Portland Cement into three grades:
33 Grade
43 Grade
53 Grade
33 Grade
43 Grade
53 Grade
The Compressive Strength of these Cements at 28 days should not be less than 33 N/mm2, 43 N/mm2 & 53 N/mm2 respectively.
Properties Of Ordinary Portland Cement:
It's residue by weight is not to exceed 10% when sieving through Is sieve number 9.
In the Soundness Test, it's expansion is not more than 10mm.
It's initial Setting Time is not less than 30 minutes and Final Setting Time not more than 10 hours.
The Compressive Strength of 33 grade opc after 3 days, 7 days & 28 days should not be less than 16 N/mm2, 22 N/mm2 & 33N/mm2 respectively.
The Compressive Strength of 43 grade opc after 3 days, 7 days & 28 days should not be less than 23 N/mm2, 33 N/mm2 & 43N/mm2 respectively.
The Compressive Strength of 53 grade opc after 3 days, 7 days & 28 days should not be less than 27 N/mm2, 37 N/mm2 & 53N/mm2 respectively.
It's residue by weight is not to exceed 10% when sieving through Is sieve number 9.
In the Soundness Test, it's expansion is not more than 10mm.
It's initial Setting Time is not less than 30 minutes and Final Setting Time not more than 10 hours.
The Compressive Strength of 33 grade opc after 3 days, 7 days & 28 days should not be less than 16 N/mm2, 22 N/mm2 & 33N/mm2 respectively.
The Compressive Strength of 43 grade opc after 3 days, 7 days & 28 days should not be less than 23 N/mm2, 33 N/mm2 & 43N/mm2 respectively.
The Compressive Strength of 53 grade opc after 3 days, 7 days & 28 days should not be less than 27 N/mm2, 37 N/mm2 & 53N/mm2 respectively.