circular concrete tank formula

huangyhg

circular concrete tank formula
would anybody have pca 'circular concrete tanks without prestressing' publication handy to give me a formula for wall thickness calkulation?? thanks.
check out our whitepaper library.
wall thickness = [(ces + fs - nfc)/(12*fc*fs)]*t
where c = coeff of concrete shrinkage at 0.0003 in/in
es = modulus of elasticity of reinforcing steel = 29000 ksi
fs = allow tension in rebar typically kept low at 18 ksi
fc = 28 day concrete strength x 0.10
n = modular ratio = es/ec where ec = 57*square root of f'c
t = ring wall tension anticipated based on fixity conditions