Estimating Sheet

# Some useful guidelines for designing the RCC slab

Construction Software In this construction video tutorial, the renowned engineer, Sami Ullah, introduces some useful guidelines which are essential to create the design of any RCC slab.

This video is very vital for civil engineering students.

The steel bars having least diameter of 12 mm should be applied for RCC slab.

Highest diameter of steel bars should not be in excess of D/8 (D signifies depth of RCC slab).

In case, the thickness of the slab is 6 inches, then the maximum diameter of steel bar will be 6/8.

Maximum spanning of main bar should be 3D or 300 mm (D denotes depth of RCC slab).

In case, the depth of the slab is 3 inches, then the maximum spanning should be 3 x 6 = 18 inches or 1.5 feet.

Maximum spanning for distribution bar should be 5D or 450 mm.

Minimum spanning for main bar and distribution bar should not be under 75 mm in RCC slab.

The depth for one way and two way slab should be L/22 to L/28 (here, L denotes length of the slab). It is based on thumb rules.

In case, the length of the slab is 14 feet, the depth will be 14/22 = 0.63 feet. To covert the value in inches, multiply with 12 i.e. 0.63 x 12 = 7.56 inches.

In RCC slab, the percentage of the steel should be 0.2% to 0.5% with X cross section area.

In case the cross section area of the slab is 25 feet, then the quantity of steel should be 25 x 0.2 = 5 feet

To get more details with graphical representation, go through the following video tutorial.

Video Source: Sami Ullah 