Question

As per India standard code of practice for prestressed concrete (IS:1343-1980) the minimum grades of concrete to be used for post-tensioned and pre-tensioned structural elements are respectively
1. M 20 for both
2. M 40 and M 30
3. M 15 and M 20
4. M 30 and M 40

Answer 1

Correct Answer - Option 4 : M 30 and M 40

Concept:

A minimum grade of concrete to be used in the design of the prestressed concrete structure as per IS 1343 is as below:

1. For Post-tensioning minimum grade of concrete used is M-30.

2. For Pre-tensioning minimum grade of concrete used is M-40.

Cover to be used in the design of the prestressed concrete structure as per IS 1343 is as below:

1. For Post-tensioning minimum cover to be used is 30 mm.

2. For Pre-tensioning minimum cover to be used is 20 mm.