The structure is made with Reinforce cement concrete (RCC) material.
It is a combination of bars and cement with strong bonding between them. Bars are provided to resist tensile as well as compressive stresses. Thus it's very important to make a strong bond between concrete and Reinforced bars.
If small diameter bars(also called distribution bars) are used more in quantity, increase the surface area of steel, and thus bonding area of reinforcement bars and cement increase. Thus bond becomes stronger and avoids cracks in the future.
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