Percentage of steel in RCC Structures as per IS 456 : 2000

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    RCC (Reinforced Cement Concrete) is the concrete in which the steel is provided within the concrete to increase the tensile strength of the concrete structure. Concrete has very high compressive strength but it has very low tensile strength. To overcome this steel reinforcement is provided inside the concrete. At the same time both concrete and steel have the same properties like both have nearly the same or similar thermal expansion hence when they expand or contract due to environmental changes both expand or contract at the same rate. Steel can last up to 100 years if it is not exposed to open air with water.

    There are some percentages of steel the each structural member like Footing, Column, Beam, and slabs. This percentage of steel is set by the standards of each country based on their country's geographical and environmental conditions. If you want to know who set all these standards in each country check out our article "Code of Practice or Standards for Civil Engineering".

IS 456: 2000

Steel Requirement for Slabs as per IS 456: 2000

1. Minimum - 0.15% of the cross-sectional area of the slab on either side of the beam, this can be reduced to 0.12% of the cross-sectional area of the Slab.

    

    Note: The Diameter of the bar should not exceed 1/8th of the thickness of the slab. For example, let's take the slab thickness as 150mm then 1/8th of the slab is 18.75mm that means you can use up to 16mm diameter rod in the slab since 18mm diameter rods were not available in the markets of India.

Steel Requirement for Beams as per IS456: 2000

1. Minimum - Not less than 0.8% of the cross-sectional area of the column
2. Maximum - Not more than 6% of the cross-sectional area of the column

    Note: In a Rectangular Column minimum of 4 numbers of main rods need to be provided and in a circular column minimum of 5 numbers of main rods need to be provided. In Columns the main rods need not be less than 12mm in diameter.