Tand diameterTank shell height

Design liquid levelSpecific gravity of liquid

Allowable design stressAllowable stess in tension ring

Minimum yield strength of all steelSpecified corrosion allowane

Tank bottom plate thickness

Design external pressure (gauge)Design wind velocityMaximum wind pressureDesign snow loadRoof design live loadMofulus of elasticityShell course height and thicknesses calculated by the one foot method are as follows

Required MinimumCoruse (H-1) Thickness ThicknessNumber (ft) (in) (in)

1 7 0.059 5/162 15 0.126 5/163 23 0.193 5/164 31 0.261 5/165 39 0.328 0.3286 47 0.395 0.395

Calculate the transformed shell heightActual Shell Transformed Shell

Course Course Height Thickness Course HeightNumber (ft) (in) (ft)

1 8 0.3125 8.002 8 0.3125 8.003 8 0.3125 8.004 8 0.3125 8.005 8 0.328 7.096 8 0.395 4.45

Sum = 48 Sum = 43.54

Check that buckling will occur elastically in the unstiffened cylindrical shell

Minimum thickness of thinnest shell course

Transformed height of tank shell

Buckling ratioBuckling will occur elastically

Calculate the minimum shell thickness tequired for the combined loading from design external pressure and wind

Total design external pressure for design of shell

Required minimum shell thickness

The required thickness is greater than the available thickness and the shell must be stiffened

Calculate the macimum spacing of intermediate stiffeners

Maximum height of unstiffened shell permitted based on the calculated minimum thickness

D 75 ftH 48 ft

48 ft

23,200 lb/in^2f 21,600 lb/in^2

36,000 lb/in^20

3/8 in

0.6 lb/in^2 Min Value 0.036 lb/in^2 0.248211 kPaV 120 mph Max Value 1 lb/in^3 6.89476 kPaW 31 lb/ft^2S 0 lb/ft^2

E 30,000,000 lb/in^2

Transformed ShellCourse Height

(ft)8.008.008.008.007.094.45

43.54

0.3125 in

43.54 ft

1.23

Calculate the minimum shell thickness tequired for the combined loading from design external pressure and wind

86.4 lb/ft^2

0.698 in

Hin

Sd

Fy

tb

Pe

tsmin

HTS

R Buckling

Ps

tsmin required

2.8369E-25Hsafe

Course Actual Shell Thickness Transformed ShellNumber Course Height (in) Course Height

(ft) (ft)1 8 0.3125 82 8 0.3125 83 8 0.3125 84 8 0.3125 85 8 0.328 7.08810972562566 8 0.395 4.4537137663537

48 43.541823491979