Reinforced Concrete Slab and Maximum Size of Reinforced Bar

Reinforced concrete slabs are used in construction for their strength and durability. They are made by pouring concrete into a formwork and then reinforcing it with steel bars. The thickness of a reinforced concrete slab is an important factor in determining the size of the reinforced bar that can be used.

Maximum Size of Reinforced Bar

The maximum size of the reinforced bar that can be used in a concrete slab is determined by the thickness of the slab. The general rule is that the diameter of the bar should not exceed one-eighth of the thickness of the slab. For example, if the slab is 75 mm thick, the maximum diameter of the reinforced bar that can be used is:

Maximum bar diameter = 75 mm/8 = 9.375 mm

However, the actual maximum size of the reinforced bar that can be used is usually rounded down to the nearest even number. This is because odd-numbered bars are not readily available in the market and require special ordering.

Therefore, the correct answer to the given question is option 'C' which is 8 mm diameter. This is because 8 mm is the largest even number that is less than or equal to 9.375 mm.

Conclusion

The maximum size of the reinforced bar that can be used in a concrete slab is determined by the thickness of the slab. The general rule is that the diameter of the bar should not exceed one-eighth of the thickness of the slab. The actual maximum size is usually rounded down to the nearest even number. In the case of a 75 mm thick reinforced concrete slab, the maximum size of the reinforced bar that can be used is 8 mm in diameter.

Code recommend that maximum dia of bar in slab should not be greater 1/8 of total thickness
if 75 mm thickness then dia will be 75/8 = 9.3 thus maximum dia will be 8mm because 9mm dia bar is not available