Circular Slab
Circular Slab
(OP)
Hello
I am designing a pedestal with a circular slab of diameter 50 feet supported on a circular wall of 8" thick and 38 feet outer diameter. The thickness of the slab is 28" (governed by shear design)
I am looking for a good example for two-way reinforcement detail. Can someone give me any suggestion on how to proceed. Thank you.
I am designing a pedestal with a circular slab of diameter 50 feet supported on a circular wall of 8" thick and 38 feet outer diameter. The thickness of the slab is 28" (governed by shear design)
I am looking for a good example for two-way reinforcement detail. Can someone give me any suggestion on how to proceed. Thank you.






RE: Circular Slab
BA
RE: Circular Slab
Self Wt of Slab = (145 lb/ft^3)* thickness (2.33') = 0.34 kips/ft^2
Wt of Water = 438000 Gal = (438000*8.33)/(pi/4*48^2)=2.02 kips/ft^2 ------------- (8.33 is the conversion of Gal to lb and 48 is the diameter of the steel tank). This load as the area load over 48' diameter
Wt of Steel Tannk = 40750 lb = 40750/(pi*d) = 40750/(pi*48) = 0.27 kips/ft
Wt. of Snow load = 30 psf (Act as a line load along the circumference of the tank) = (30*pi*48^2)/(pi*48) = 0.360 kips/ft
Note: For simplicity snow load is taken as dead load
Load Combination = 1.4*(Dead load+Water Load)
Hope this will clearly explain my whole problem
RE: Circular Slab
Provide two way bottom reinforcement for maximum positive moment. Provide two way top reinforcement for maximum negative moment. Provide nominal circumferential bars on edge of slab.
BA
RE: Circular Slab
Please confirm my reinforcement detail
I got my negative and positive moment from RISA model. I want to check it with hand calculation. So is there anyway I can calculate moments for given loading.
RE: Circular Slab
RE: Circular Slab
Though, as BARetired suggests, a circumferential bar at the edge of the slab is a good idea. But, that's just to better control localized shrinkage cracking in locations where the orthogonal bars don't have sufficient development length.
RE: Circular Slab