Give the physical characteristics of 53 grade OPC.
OPC means Ordinary Portland Cement. If the 28 days strength is not less than 53 N/mm2. It is called as 53 grade cement as per IS: 4031-1988.
OPC 53 grade cement is manufactured as per specification laid down by ministry of railways under IRS:T40-1985. It is a very finely ground cement with high C3S content designed to develop high early strength.
What is an air entraining agents? Give some examples. What is efflorescence in concrete structure?
What are flaky and elongated aggregates? How can the shape of aggregate influence strength of concrete? Following is the result of a sieve analysis of 500 gm aggregate:
| IS sieve size | 10 mm | 4.75 mm | 2·36 mm | 1·18 mm | 600 micron | 300 micron | 150 micron | lower than 150 micron |
| Weight retained in gm | 0 | 10 | 50 | 50 | 95 | 175 | 85 | 35 |
Find out the 'Fineness Modulus' of the sample
