Question

The maximum tension reinforcement an RCC beam can have is

Where b = width of the beam; D = depth of the beam

1. 6% bD
2. 4% bD
3. 2% bD
4. 0.2% bD

Answer 1

Correct Answer - Option 2 : 4% bD

Explanation:

• Steel reinforcing rods are used in concrete beams to make them carry tension.
• As concrete is strong in compression but weak in tension and its tensile strength is approx 1/10th of compressive strength. To improve its tensile strength, reinforcement ( steel reinforcing rods ) is embedded in it.
• As per IS 456 maximum area of tension reinforcement in the beam shall not exceed 4% of the total area i.e. 4% of bD or 0.04bD

S ome other provision is given by IS 456:

• The minimum area of tensile reinforcement = \(\frac{{{A_{st}}}}{{bd}} = \frac{{0.85}}{{{f_y}}}\)
• Nominal cover =  25 mm
• Ultimate tensile strain in steel is in the range of = 0.12% to 0.2%