Two terms are generally used in the reinforcements of slabs. Main bars and Distribution bars, in this post we are going to explain you the difference between main bar and distribution bar in slab the concept was explained in simple words so you can easily understand, their differences and where these bars are provided in R.C.C slab.
MAIN BARS IN SLAB:
1. The main reinforcement is to be provided at the shorter span of the slab. In the shorter span slab faces Highbending Moment which is known as sagging or positive bending moment.
2. Main reinforcement bars will counter or responsible for taking all the tensile stresses, bending moment (Sagging), and superimposed load (Dead load) which developed at the shorter span of the slabs.
3. Main reinforcement bars are provided in one way slab in one side (At shorter span), but in the two-way slab, we provided bars in both ways.
4. In Flat plate slabs, the main bars are provided in one direction at bottom of the distribution bar (in shorter span).
5. Main bars in the slabs won’t be less than 8 mm if you are using (H.Y.S.D) or 10 mm if you are using (Plain bars).
DISTRIBUTION BARS IN SLAB:
1. Distribution reinforcement bar is to provide at the longer side span of the slab.
2.Distribution bar is designed to distribute the superimposed load equally or counter the Shrinkagestresses which are developed due to Temperaturevariation (Winter, Summer).
3. In Flat plate slab, the Distribution bars are provided in one direction at Top of the main bar (in longer span).
4. The distribution bars aren’t less than 8 mm in diameteror not be more than 1/8 of the thickness of the R.C.C slabs.
5. The distribution bars are provided to hold the mesh in position and maintain the centre to centre c/c, bars spacing between main bars.
DIFFERENCE BETWEEN MAIN BARS AND DISTRIBUTION BARS:
1. The Main bars are normally provided at the bottom of distribution bar in slabs But Distribution bars are provided on the top of the main bar.
2. The Main bars are provided in the shorter span of the slabs But Distribution bars are provided in the longer span of the slabs.
3. The main reinforcement was provided to counter the bending moment, tensile stresses and superimposed load But Distribution bars are used to distribute the load equally, resist the shrinkage stress (Temperature variation) or hold the mesh in his desired position.
4. Main bars in the slab won’t be less than 8 mm if you are using (HYSD) or 10 mm if you are using (Plain bars)and the Distribution bars is also not less than 8 mm diameter and the bar won’t be more than 1/8 of the thickness of the slab.
watch this article video on YouTube for your better understanding. This video was in Hindi.