OPC comes in three different grades, including 33 grade, 43 grade and 53 grade. Due to weak compressive strength, 33 grade is normally not opted where high grade of concrete viz, M-20 and above is required. 43 grade is widely used for its multiple applications. This grade is very popular in the construction industry. 53 grade has high strength that can match the demand of strong concrete. However, the chemical composition of OPC 33, OPC 43 and OPC 53 grades is same though the higher grade cements are much stronger and long lasting. Whereas the compressive strength of PPC matches the strength of 33 grade OPC at present, according to BIS.
What is the difference between grade 43 and grade 53 cement?
Grade 43 and grade 53 cement indicate the maximum strength achieved after 28 days. These are the most commonly used grades of cement and the differences between the two grades of cement are –
- Grade 53 cement achieves strength of 530kg/sq. cm. after 28 days while Grade 43 cement achieves strength of 430kg/sq. cm. after 28 days.
- Grade 53 cement is used for fast paced construction like bridges, roads, multistoried buildings and cold weather concrete. Grade 43 cement is used as the most widely used general purpose cement.
- Grade 53 cement has a very quick setting time and attains quick strength. The strength does not increase much after 28 days. Grade 43 cement has a low initial strength but gains good strength over a period of time.
- Grade 53 Cement sets fast and releases higher heat of hydration while Grade 43 Cement releases very low heat of hydration. As a result there are chances of micro cracks which are not visible on the surface in Grade 53 Cement and proper curing should be done.
- Grade 53 cement is slightly costlier than Grade 43 Cement