Statement I): Torsion reinforcement is provided at (and near) corners in a two-way slab which is simply supported on both edges meeting at the corner. Statement II): The area of reinforcement in each of the layers shall be three-quarters of the area required for maximum mid-span moment in the slab.
Statement I): Torsion reinforcement is provided at (and near) corners in a two-way slab which is simply supported on both edges meeting at the corner. Statement II): The area of reinforcement in each of the layers shall be three-quarters of the area required for maximum mid-span moment in the slab. Correct Answer Both Statement I) and Statement II) are individually true, but Statement II) is not the correct explanation of Statement I)
As per IS 456:2000, Annexure-D, D-1.8,
Torsion reinforcement shall be provided at any corners in a two-way slab which is simply supported on both edges meeting at the corner.
It shall consists of top and bottom reinforcement, each with layers of bars placed parallel to the side of the slab and extending from the edges a minimum distance of 1/5th of the shorter span.
The area of reinforcement in each of these four layers shall be three-quarters of the area required for maximum mid-span moment in the slab.
Other provisions about torsional reinforcement in two-ways labs as per IS 456:2000
1. Torsional reinforcement need not be provided at any corner where both edges are continuous.
2. Torsional reinforcement of 50 % of three-quarters of the area required for maximum mid-span moment in the slab shall be provided at a corner contained by edges over only one of which the slab is continuous.
