Step by step on how to design a distillation column with all equations and formulas. Provides in depth analysis to the procedure, application and method involved.
1. Average N= 15 Average unconfined strength corresponding to N=15 Cu=10.19t/m2 Average = 10.19/2 =5.09t/m 2 Say, 5t/m2 2. safe bearing capacity of soil = 5.14X5.0/2.5 = 10.28t/m 2 Lets take the S.B.C as 10.5t/m 2 3. Average unit weight = 1.83t/m 2 Submerged unit weight = 0.83t/m 2 4. Nominal diameter of stone column = 500mm Increased size after installation = 600mm 5. Critical depth = 4D = 4X0.6 = 2.40m 6. Initial radial stress in the soil ros = k 0ˠˈH K 0 = 0.6 ros = 0.6 X 0.83 X 2.40 = 1.1952t/m2 7. Radial stress in the soil due to surcharge effect equivalent 10.5 rss = 0.6 X 10.5 = 6.3t/m2 8. Vertical stress in the stone column 2 rc = tan {45+ᶲc /2}[f c+ ros+ rss] ᶲc = 30͘
F=4 C=5 tan2 [45++ᶲc /2] = 3 rc= 3 X [4 X 5 +1.1952+6.3] = 82.4856t/m 2 9. Ultimate load carried by a stone column = 82.4856 X /4 X 0.62 = 23.322t say 23.0t 10. Load at ground level Weight of water = Π/4 X 39 2 X 20.7 X 1 = 24728.025t =24729t Self weight of the tank = 508t Total weight = 25237t 11. Thickness of sand pad = 1m Offset = 1m Distribution of load assumed as 1t Pressure on soil at ground level = 25237t / Π/4 [39+2X1.0] 2 = 19.124t/m2
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12.0 Disposition of stone column: Equi- spacing of column at 1.25m Intervals on an equi-interval Triangular grid pattern 12.1 Load at ground level = 19.124t/m 2 Spacing of columns, S=1.25m Tributary area of a column A = 0.866 (1.25) 2 = 1.353m2 Area of stone column: A p = Π/4 X 0.62 = 0.283m 2 a= A p/A =0.283/1.353 = 0.209 ; say 0.21 12.2 Elastic modulus of soil: ES = 300t/m2 (assumed) Elastic modulus of stone column: E p = 3300 (assumed) 13. Equivalent modulus of soil stratum, reinforced with stone column Eeq = αE p+(1-α) ES = 0.210 X 3300 + (1-0.210) X 300 = 930t/m2 q p= 19.124 X 3300/ 930 = 67.85t/m2 Q p=67.85 X 0.283 = 19.20 F.S = 23.0/19.20 = 1.197 = 1.2 qs= 19.124 X 300/ 930 = 6.16t/m2 Stone column to be terminated in a cohesion less soil stratum, vide recommendation in the report. Depth of stone column will range from 7.5 to 9.5m.