Question

Design calculation of circular overhead water tank

Answer 1

7 step design procedure for RCC Circular Water Tank

In our previous article, we discussed some important theory and formulas required in the design procedure of Circular Water Tank.

Refer: Important theory and formula derivation for Circular Water Tank

Circular Water tank

We will now move on with the stepwise design procedure for Water tank design.

Step One

Determine the design constants such as σcbc, σct, m, σst

Where,

σcbc = permissible compressive stress in concrete

σct = permissible tensile stress in concrete

m = modular ratio

σst = permissible compressive stress in steel

Step two

Determine:

Dimensions of the tank

Volume of the tank

Area of the tank (by assuming its depth)

Refer: How to calculate Water Tank Capacity?

Step three:

Find:

Hoop tension, Ht = d x h x D/2

Area of steel, Ast = d x h x D/2 σst

Step four:

Thickness of the wall of water tank

Ht = [1000t + (m – 1)Ast] x σct

Step five

Reduction in hoop steel. The steel calculated in step 3 is for 1m height from the bottom of the water tank. The pressure of water decreases at the top. Hence, steel can be reduced by keeping the same thickness of wall.

Step six

Distribution steel (vertically placed)

Ast = 0.3% of Ag

Step seven

Floor of the tank

Provide 0.3% of Ag both ways

We will also do some good examples for the circular water tank in our succeeding articles.

Answer 2

Answer:

l=4m,b=3.2m&h=1400 cm