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Technical particles acts as an anchor and keeps the while before sinking, then it is of superior aggregate particles in together with the quality. Sometimes, the cement may sink real concrete mix. fast. This happens due to the presence of So what are grades in cement? Ordinary Portland Cement is graded according to strength, the cements too have to gain a particular strength. 33, 43 and 53 grade in OPC indicates the compressive strength of cement after 28 days when tested as per IS: 40311988, eg, 33 Grade means that 28 days of compressive strength is not less than 33 N/mm2 (MPa) . Similarly for 43 grade and 53 grade the 28 days compressive strength should not be less than 43 and 53 MPa respectively. 43 and 53 grade are also being introduced in PPC and PSC shortly by the Bureau of Indian Standards (BIS) How to check the quality of cement Before you send a sample of cement and concrete to the labs, you can check the quality of cement out of the bag only. Make sure that impurities. Cement being used should be within 6 weeks from the manufactured date. After purchasing the cement, make sure that the cement bags are placed close together without any presence of moisture and air circulation. Which cement should we use? Frankly speaking, b