Q. As per IRC recommendations, the sub-grade or sub-base layer whatever underlies the concrete wearing slab, in concrete pavements, must confirm to the requirement that (Solved)
1. no soft spots are present in the sub-grade or sub-base
2. the base or sub-base extends to atleast 30 cm wider on either side of the width to be concreted
3. the sub-grade is properly drained
4. all of the above
- d. all of the above