Reinforcing Configuration in Circular Tank Base Slab

[mrengineer]

I am detailing a circular base slab for a 30 foot diameter clarifier tank. The walls have been designed for hoop stress, and therefore no real structural demands on base slab other than water tightness concerns. I am trying to decide whether to simply have straight bars two ways in the slab (variable length), or provide radial bars originating from center of tank in combination with circular bars of variable diameter. Does anyone have any druthers one way or the other?
Thanks

 

[pappyirl]

I would use a rectangular grid of staright bars for ease of placement. More bar varieties are used and you will have to use Wood Armer or some other equivalent moment method to work out the reinforcement areas required.

For the radial bars, how do you intend to lap them at the centre of the base?