Solution:

IS 456-2000 Plain and Reinforced Concrete – Code of Practice is an Indian Standard code of practice for general structural use of plain and reinforced concrete. The latest revision of this standard was done in year 2000, reaffirmed 2005. This code uses the limit state design approach as well working stress design approach. It is written for use in India. It gives extensive information on the various aspects of concrete. As per the rule the diameter of the reinforcing bars in slabs shall not exceed one eighth of the total thickness of the slab.