TABLE OF CONTENTS
SUMMARY OF DESIGN DATA AND REMARKS
ROOF DESIGN
ROOF SUMMARY OF RESULTS
SHELL COURSE DESIGN
SHELL SUMMARY OF RESULTS
BOTTOM DESIGN
BOTTOM SUMMARY OF RESULTS
WIND MOMENT
SEISMIC SITE GROUND MOTION
SEISMIC CALCULATIONS
ANCHOR BOLT DESIGN
ANCHOR BOLT SUMMARY OF RESULTS
CAPACITIES AND WEIGHTS
Warnings!!
Initial Data
1.- Design internal pressure is greater than maximum allowable working pressure (MAWP). 2.- Design external pressure is greater than maximum allowable working vacuum (MAWV). Shell Course Data
1.- Please revise the shell thk, 3 courses have problems.
2.- The required minimum thickness based on external pressure is greater than the available thickness and the shell must be stiffened.
Top Member Data
1.- Design pressure is greater that maximum allowable pressure 2.- Reinforcement needed due to insufficient cross sectional area.
3.- Reinforcement needed due to insufficient combined stiffener shell moment of inertia. Intermediate Stiffener Data
1.- Number of intermediate stiffeners is less than required. Revise shell thicknesses or add stiffeners. Structure Data
1.- Please revise the Structure, there is a problem in the sizes. Shell Clean Outs
Clean-Out-0001
1.- Please revise the bottom plate thickness, has problem. Shell Pipe Overflows
Pipe-Overflow-0001
1.- Re Pad thickness is less than min req'd.
SUMMARY OF DESIGN DATA AND REMARKS
Back
Job : 2014-6-20-9-46
Date of Calcs. : 8/11/11
Mfg. or Insp. Date : Designer : TCB
Project : Tag Number :
Plant : PURCHASER DESCRIPTION CITY AND STATE Plant Location :
Site :
Design Basis : API-650 12th Edition, March 2013
TANK NAMEPLATE INFORMATION
Pressure Combination Factor 0.4
Design Standard API-650 12th Edition, March 2013 Appendices Used
Roof A36 : 0.1875 in
Shell (2) A36 : 0.5625 in
Shell (3) A36 : 0.3125 in
Shell (4) A36 : 0.3125 in
Shell (5) A36 : 0.3125 in
Bottom A36 : 0.25 in
Design Internal Pressure = 0.1 psi or 2.7682 inh2o
Design External Pressure = -0.06 psi or -1.6609 inh2o
MAWP = 0.0764 psi or 2.1165 inh2o
MAWV = -0.0575 psi or -1.5915 inh2o
D of Tank = 150 ft
OD of Tank = 150.125 ft
ID of Tank = 150 ft
CL of Tank = 150.0625 ft
Shell Height = 40 ft
S.G of Contents = 1
Max Liq. Level = 40 ft
Min Liq. Level = 2 ft
Design Temperature = 120 ºF
Tank Joint Efficiency = 1
Ground Snow Load = 0 psf
Roof Live Load = 20 psf
Additional Roof Dead Load = 0 psf
Basic Wind Velocity = 125 mph
Wind Importance Factor = 1
Using Seismic Method: API-650 - ASCE7 Mapped(Ss & S1)
DESIGNER REMARKS
Remarks or Comments
SUMMARY OF SHELL RESULTS
She ll # Widt h (in) Materi al C A (in ) J E Min Yield Strengt h (psi) Tensile Strengt h (psi) Sd (psi) St (psi) Weigh t (Lbf) Weigh t CA (Lbf) t-min Erectio n (in) t-Des (in) t-Test (in) t-min Seismi c (in) t-min Ext-Pe (in) t-min (in) t-Actu al (in) Statu s 1 96 A36 0 1 36,000 58,000 23,20 0 24,90 0 115,29 7 115,29 7 0.3125 0.655 6 0.610 8 0.5087 0.435 9 0.655 6 0.75 OK 2 96 A36 0 1 36,000 58,000 23,20 0 24,90 0 86,482 86,482 0.3125 0.521 1 0.485 5 0.4062 0.435 9 0.521 1 0.562 5 OK 3 96 A36 0 1 36,000 58,000 23,20 0 24,90 0 48,052 48,052 0.3125 0.386 6 0.360 2 0.3029 0.435 9 0.435 9 0.312 5 FAIL 4 96 A36 0 1 36,000 58,000 23,20 0 24,90 0 48,052 48,052 0.3125 0.252 2 0.234 9 0.199 0.435 9 0.435 9 0.312 5 FAIL 5 93 A36 0 1 36,000 58,000 23,20 0 24,90 0 46,550 46,550 0.3125 0.117 7 0.109 6 0.0948 0.435 9 0.435 9 0.312 5 FAIL
Total Weight of Shell = 344,435.3686 lbf
Plates Material = A36
Structural Material = A36
t.required = 0.1875 in
t.actual = 0.1875 in
Roof corrosion allowance = 0 in
Roof Joint Efficiency = 1
Plates Overlap Weight = 2,136.0223 lbf
Plates Weight = 135,679.1475 lbf
RAFTERS:
Qty At Radius (ft) Size Length (ft) W (lbf/ft) Ind. Weight (lbf) Total Weight (lbf)
40 37.5 W10X12 35.2765 12 423.3185 16,932.7414
80 74.9052 W10X22 40.926 22 900.374 72,029.9234
Rafters Total Weight = 88,962.6649 lbf
GIRDERS:
Qty At Radius (ft) Size Length (ft) W (lbf/ft) Ind. Weight (lbf) Total Weight (lbf)
8 37.5 W12X50 28.7012 50 1,435.0628 11,480.5029
Girders Total Weight = 11,480.5029 lbf
COLUMNS:
Qty At Radius (ft) Size Length (ft) W (lbf/ft) Ind. Weight (lbf) Total Weight (lbf)
1 0 10" SCH STD 43.6853 40.5207 1,770.1605 1,770.1605
8 37.5 10" SCH STD 40.4587 40.5207 1,640.1602 13,121.2819
Columns Total Weight = 14,891.4425 lbf
Bottom Type : Flat Bottom Annular
Bottom Material = A36
t.required = 0.236 in
t.actual = 0.25 in
Bottom corrosion allowance = 0 in
Bottom Joint Efficiency = 1
Total Weight of Bottom = 175,797.7572 lbf
TOP END STIFFENER : Detail D
Size = l3x3x3/8 Material = A36
STRUCTURALLY SUPPORTED CONICAL ROOF
Back
A = Actual Part. Area of Roof-to-shell Juncture per API-650 (in^2)
A-min = Minimum participating area (in^2) per API-650 5.10.5.2
a-min-A = Minimum participating area due to full design pressure per API-650 F.5.1 (in^2)
a-min-Roof = Minimum participating area per API-650 App. F.5.2 (in^2)
Add-DL = Added Dead load (psf)
Alpha = 1/2 the included apex angle of cone (degrees)
Aroof = Contributing Area due to roof plates (in^2)
Ashell = Contributing Area due to shell plates (in^2)
CA = Roof corrosion allowance (in)
D = Tank Nominal Diameter per API-650 5.6.1.1 Note 1 (ft)
density = Density of roof (lbf/in3)
DL = Dead load (psf)
e.1b = Gravity Roof Load (1) - Balanced (psf)
e.1u = Gravity Roof Load (1) - Unbalanced (psf)
e.2b = Gravity Roof Load (2) - Balanced (psf)
e.2u = Gravity Roof Load (2) - Unbalanced (psf)
Fp = Pressure Combination Factor
Fy = smallest of the yield strength (psi)
Fy-roof = Minimum yield strength for shell material (Table 5-2b) (psi)
Fy-shell = Minimum yield strength for shell material (Table 5-2b) (psi)
Fy-stiff = Minimum yield strength for stiffener material (Table 5-2b) (psi)
hr = Roof height (ft)
ID = Tank Inner Diameter (ft)
Insulation = Roof Insulation (ft)
JEr = Roof joint efficiency
Lr = Entered Roof Live Load (psf)
Lr-1 = Computed Roof Live Load, including External Pressure
Max-p = Max Roof Load due to participating Area (psf)
Net-Uplift = Uplift due to internal pressure minus nominal weight of shell, roof and attached framing (lbf), per API-650 F.1.2
P = Minimum participating area (psf)
P-ext-2 = Max external pressure due to roof shell joint area (psi)
P-F41 = Max design pressure limited by the roof-to-shell joint (inH2O)
P-F42 = Max design pressure due to Uplift per API-650 F.4.2 (inH2O)
P-F51 = Max design pressure reversing a-min-A calculation (psf)
P-max-ext-T = Total max external pressure due to roof actual thickness and roof participating area (psi)
P-max-internal = Maximum design pressure and test procedure per API-650 F.4, F.5. (psf)
P-Std = Max pressure pressure allowed per API-650 App. F.1 & F.7 (psi)
P-Uplift = Uplift case per API-650 1.1.1 (lbf) P-weight = Dead load of roof plate (Psf)
Pe = External Pressure (psf)
pt = Roof cone pitch (in) rise per 12 (in)
Pv = Internal Pressure (psf)
R = Roof horizontal radius (ft)
Ra = Roof surface area (in^2)
Roof-wc = Weight corroded of roof plates (lbf)
S = Ground Snow Load per ASCE 7-05 Fig 7-1 (psf)
Sb = Balanced Design Snow Load per API-650 Section 5.2.1.h.1 (psf)
Shell-wc = Weight corroded of shell (lbf)
Su = Unbalanced Design Snow Load per API-650 Section 5.2.1.h.2 (psf)
T = Balanced Roof Design Load per API-650 Appendix R (psf)
t-calc = Minimum nominal roof plates thickness per API-650 Section 5.10.5.1 (in)
t-Ins = thickness of Roof Insulation (ft)
Theta = Angle of cone to the horizontal (degrees)
U = Unbalanced Roof Design Load per API-650 Appendix R (psf)
Wc = Maximum width of participating shell per API-650 Fig. F-2 (in)
Roof Design Per API-650
Note: Tank Pressure Combination Factor Fp = 0.4
D = 150 ft
ID = 150 ft
CA = 0 in
R = 75.0677 ft
Fp = 0.4
JEr = 1
JEs = 1
JEst = 1
Insulation = 0 ft
Add-DL = 0 psf
Lr = 20 psf
S = 0 psf
Sb = 0 psf
Su = 0 psf
density = 0.2833 lbf/in3
P-weight = 7.6779 Psf
Pe = 8.64 psf
pt = 0.75 in rise per 12 in
t-actual = 0.1875 in Fy-roof = 36,000 psi
Fy-shell = 36,000 psi
Fy-stiff = 36,000 psi
Shell-wc = 344,435.3686 lbf
Roof-wc = 135,679.1475 lbf
P-Std = 2.5 psi, Per API-650 F.1.3
t-1 = 0.3125 in CA-1 = 0 in Sd = 23200 psi
Theta = TAN^-1 (pt/12)
Theta = TAN^-1 (0.75/12)
Theta = 3.5763 degrees
Alpha = 90 - Theta
Alpha = 90 - 3.5763
Alpha = 86.4237 degrees
Ap-Vert = D^2 * TAN(Theta)/4
Ap-Vert = 150^2 * TAN(3.5763)/4
Ap-Vert = 351.5625 ft^2
Horizontal Projected Area of Roof per API-650 5.2.1.f
Xw = D * 0.5
Xw = 150 * 0.5
Xw = 75 ft
Ap = PI * (D/2)^2
Ap = PI * (150/2)^2
Ap = 17,671.4586 ft^2
DL = Insulation + P-weight + Add-DL
DL = 7.6779 psf
Roof Loads per API-650 5.2.2
e.1b = DL + MAX(Sb , Lr) + (0.4 * Pe)
e.1b = 7.6779 + MAX(0 , 20) + (0.4 * 8.64)
e.1b = 31.1339 psf
e.2b = DL + Pe + (0.4 * MAX(Sb , Lr))
e.2b = 7.6779 + 8.64 + (0.4 * MAX(0 , 20))
e.2b = 24.3179 psf
T = MAX(e.1b , e.2b)
T = MAX(31.1339 , 24.3179)
T = 31.1339 psf
e.1u = DL + MAX(Su , Lr) + (0.4 * Pe)
e.1u = 7.6779 + MAX(0 , 20) + (0.4 * 8.64)
e.1u = 31.1339 psf
e.2u = DL + Pe + (0.4 * MAX(Su , Lr))
e.2u = 7.6779 + 8.64 + (0.4 * MAX(0 , 20))
e.2u = 24.3179 psf
U = MAX(e.1u , e.2u)
U = MAX(31.1339 , 24.3179)
U = 31.1339 psf
Lr-1 = MAX(T , U)
Lr-1 = MAX(31.1339 , 31.1339)
Lr-1 = 31.1339 psf
Ra = PI * R * SQRT(R^2 + hr^2) Ra = PI * 75.0677 * SQRT(75.0677^2 + 4.6917^2) Ra = 2,554,260.9252 in^2 or 17738 ft^2
Roof Plates Weight = density * Ra * t-actual
Roof Plates Weight = 0.2833 * 2,554,260.9252 * 0.1875
Roof plates Weight = 135,679.1475 lbf
BAY 2 DETAILS
MINIMUM # OF RAFTERS
l = Maximum rafter spacing per API-650 5.10.4.4 (in)
l-actual-2 = Actual rafter spacing (in)
Max-T1-2 = Due to roof thickness (psf) N-actual-2 = Actual number of rafter
N-min-2 = Minimum number of rafter
P = Uniform pressure as determined from load combinations described in Appendix R (psi)
P-ext-1-2 = Due to roof thickness vacuum limited by actual rafter spacing (psf)
R-2 = Outer radius (in)
RLoad-Max-2 = Maximun roof load based on actual rafter spacing (psf)
t-calc-2 = Minimum roof thickness based on actual rafter spacing (in)
P = Lr-1
P = 0.2162 psi
R-2 = 898.8625 in
l = MIN(((t-Roof - CA-Roof) * SQRT((1.5 * Fy-Roof)/P)) , 84)
l = MIN(((0.1875 - 0) * SQRT((1.5 * 36,000) / 0.2162)) , 84)
l = MIN(93.705 , 84)
l = 84 in
N-min-2 = (2 * PI * R-2)/l
N-min-2 = (2 * PI * 898.8625)/84
N-min-2 = 68
N-min-2 must be a multiple of 8, therefore N-min-2 = 72.
N-actual-2 = 80
l-actual-2 = (2 * PI * R-2)/N-actual-2
l-actual-2 = (2 * PI * 898.8625)/80
l-actual-2 = 70.5965 in
Minimum roof thickness based on actual rafter spacing
t-calc-2 = l-actual-2/SQRT((1.5 * Fy-Roof)/P) + CA-Roof
t-calc-2 = 70.5965/SQRT((1.5 * 36,000)/0.2162) + 0
t-calc-2 = 0.1413 in
NOTE: Governs for roof plate thickness.
RLoad-Max-2 = (1.5 * Fy-Roof)/(l-actual-2/(t-Roof - CA-Roof))^2
RLoad-Max-2 = (1.5 * 36,000)/(70.5965/(0.1875 - 0))^2
RLoad-Max-2 = 54.852 psf
Max-T1-2 = RLoad-Max-2
Max-T1-2 = 54.852 psf
P-ext-1-2 = Max-T1-2 - DL - (0.4 * MAX(Sb , Lr))
P-ext-1-2 = 54.852 - 7.6779 - (0.4 * MAX(0 , 20))
P-ext-1-2 = -39.1741 psf
Pa-rafter-3-2 = P-ext-1-2
Pa-rafter-3-2 = -39.1741 psf
t-required-2 = MAX(0.1413 , (0.1875 + 0))
t-required-2 = 0.1875 in
RAFTER DESIGN
Average-p-width-2 = Average plate width (ft)
Average-r-s-inner-2 = Average rafter spacing on inner girder (ft)
Average-r-s-shell-2 = Average rafter spacing on shell (ft)
Max-P-2 = Load allowed for each rafter in ring (psi)
Max-r-span-2 = Maximum rafter span (ft)
Max-T1-rafter-2 = Due to roof thickness (psf) Mmax-rafter-2 = Maximum moment bending (in-lbf)
P-ext-2-2 = Vacuum limited by rafter type (psf)
R-2 = Outer radius (in)
R-Inner-2 = Inner radius (ft)
Rafter-Weight-2 = (lb/ft)
Sx-rafter-actual-2 = Actual elastic section modulus about the x axis (in^3)
Sx-rafter-Req'd-2 = Required elastic section modulus about the x axis (in^3)
Theta = Angle of cone to the horizontal (degrees)
W-Max-rafter-2 = Maximum stress allowed for each rafter in ring (lbf/in)
W-rafter-2 = (lbf/in)
SPAN TO SHELL
P = 0.2162 psi
Rafter-Weight-2 = 22 lbf/ft
Theta = 3.5763 degrees
R-2 = 903 in
R-Inner2 = 447 in
Max-r-span-2 = (R-2 - R-Inner-2)/COS(Theta)
Max-r-span-2 = (903 - 447)/COS(3.5763)
Max-r-span-2 = 40.9261 ft
Average-r-s-inner-2 = (2 * PI * R-Inner-2)/N-actual-2
Average-r-s-inner-2 = (2 * PI * 447)/80
Average-r-s-inner-2 = 2.9256 ft
Average-r-s-shell-2 = (2 * PI * R-2)/N-actual-2
Average-r-s-shell-2 = (2 * PI * 903)/80
Average-r-s-shell-2 = 5.9101 ft
Average-p-width-2 = (Average-r-s-inner-2 + Average-r-s-shell-2)/2
Average-p-width-2 = (2.9256 + 5.9101)/2
Average-p-width-2 = 4.4179 ft
W-rafter-2 = (P * Average-p-width-2) + Rafter-Weight-2
W-rafter-2 = (0.2162 * 53.0148) + 1.8333
W-rafter-2 = 13.2954 lbf/in
Mmax-rafter-2 = (W-rafter-2 * Max-r-span-2^2)/8
Mmax-rafter-2 = (13.2954 * 491.1132^2)/8
Mmax-rafter-2 = 400,844 in-lbf
Sx-rafter-Req'd-2 = Mmax-rafter-2/Sd
Sx-rafter-Req'd-2 = 400,844/23,200
Sx-rafter-Req'd-2 = 17.2778 in^3
Sx-actual-2 = 23.2 in^3
W-Max-rafter-2 = (Sx-rafter-actual-2 * Sd * 8)/Max-r-span-2^2)
W-Max-rafter-2 = (23.2 * 23,200 * 8)/491.1132^2)
W-Max-rafter-2 = 17.8526 lbf/in
Max-P-2 = (W-Max-rafter-2 - Rafter-Weight-2)/Average-p-width-2
Max-P-2 = 0.3022 psi
Max-T1-rafter-2 = Max-P-2
P-ext-2-2 = Max-T1-rafter-2 - DL - (Fp * MAX(S , Lr))
P-ext-2-2 = 43.5168 - 7.6779 - (0.4 * MAX(0 , 20))
P-ext-2-2 = -27.8345 psf
P2-rafter-3-2 = P-ext-2-2
P2-rafter-3-2 = -27.8345 psf
Limited by rafter type
GIRDER DESIGN
Average-p-width-previous-2 = Average plate width (ft)
C1-2 = (in)
C2-2 = (in)
F-Max-girder-2 = Maximum load allowed for each girder in ring (lbf)
Girder-Length-2 = Girder length (ft)
Girder-W-2 = Girder weight (lb)
Girder-W-previous-2 = Girder weight (lb)
Max-P-girder-2 = Load allowed for each rafter in ring (psi)
Max-r-span/2-actual-2 = Average maximum rafter span (ft)
Max-r-span/2-previous-2 = Average maximum rafter span previous (ft)
Max-T1-girder-2 = Due to roof thickness (psf) Mmax-girder-2 = Maximum moment bending (in-lbf)
N-columns-actual-2 = Actual number of columns
N-columns-previous-2 = Previous number of columns
N-previous-2 = Previous number of rafter
Num-Gird-actual-2 = Actual Number of girders
Num-Gird-Req-actual-2 = Required Number of girders
Num-Gird-Req-previous-2 = Required Number of girders previous
P-ext-4-2 = Vacuum limited by girder type (psi)
Pa-girder-2-2 = Vacuum limited by girder type (psi)
R-Inner-previous-2 = Inner radius (ft)
R-previous-2 = Outer radius (ft)
Sx-girder-actual-2 = Actual elastic section modulus about the x axis (in^3)
Sx-girder-Req'd-2 = Required elastic section modulus about the x axis (in^3)
W-girder-2 = Total load including weight of girder (lbf/in)
W-Max-girder-2 = Maximum stress allowed for each girder in ring (lbf/in)
W-rafter-actual-2 = (lbf/in)
W-rafter-previous-2 = (lbf/in)
W1-2 = Total rafter and roof load per girder length (lbf/in)
Wi-2 = Load due to inner rafters and roof (lbf)
Wo-2 = Load due to outer rafters and roof (lbf)
Num-Gird-actual-2 = 8
N-columns-actual-2 = 8
Girder-Length-2 = 344.4151 ft
Girder-W-2 = 50 lbf/ft
Wi-2 = W-rafter-previous-2 * Max-r-span/2-previous-2 * (Num-of-Rafters-Previous-2 / Number-of-columns)
Wi-2 = 9.2357 * 226.5 * (40 / 8)
Wi-2 = 10,390.1988 lbf
C2-2 = [(Radial-distance-next - Radial-distance-actual) / 2] * Num-Gird-Req-actual-2
C2-2 = [(900.0 - 450.0) / 2] * 10
C2-2 = 2250 in
Wo-2 = W-rafter-actual-2 * C2-2
Wo-2 = 29,914.7288 lbf
W1-2 = (Wi-2 + Wo-2)/Girder-Length-2
W1-2 = (10,390.1988 + 29,914.7288)/344.4151
W1-2 = 117.0242 lbf/in
W-girder-2 = W1-2 + Girder-W-2
W-girder-2 = 117.0242 + 4.1666
W-girder-2 = 121.1909 lbf/in
Mmax-girder-2 = (W-girder-2 * Girder-Length-2^2)/8
Mmax-girder-2 = (121.1909 * 344.4151^2)/8
Mmax-girder-2 = 1,796,985 in-lbf
Sx-girder-Req'd-2 = Mmax-girder-2/Sd
Sx-girder-Req'd-2 = 1,796,985/23,200
Sx-girder-Req'd-2 = 77.4563 in^3
Sx-girder-actual-2 = 64.2 in^3
W-Max-girder-2 = (Sx-girder-actual-2 * Sd * 8)/Girder-Length-2^2
W-Max-girder-2 = (64.2 * 23,200 * 8)/344.4151^2
W-Max-girder-2 = 100.4497 lbf/in
Let C1-2 = Max-r-span/2-previous-2 * Num-Gird-Req-previous-2
C1-2 = 226.5 * 5
C1-2 = 1125 in
Let C2-2 = [(Radial-distance-next - Radial-distance-actual) / 2] * Num-Gird-Req-actual-2
C2-2 = [(900.0 - 450.0) / 2] * 10
C2-2 = 2250 in
F-Max-girder-2 = (W-Max-girder-2 - Girder-W-2) * Girder-Length-2
F-Max-girder-2 = (100.4497 - 4.1666) * 344.4151
F-Max-girder-2 = 33,161.3307 lbf
Solve for Max-P:
Max-P-girder-2 = (F-Max-girder-2 - (Girder-W-2 * Girder-W-previous-2) - (C1-2 * Girder-W-2))/((C2-2 * Average-p-width-previous-2) + (C1-2 * Average-p-width-2))
Max-P-girder-2 = (33,161.3307 - (50 * 0) - (1125 * 50))/((2250 * 38.0918) + (1125 * 4.4179))
Max-P-girder-2 = 0.1664 psi
COLUMN DESIGN
A-actual-2 = Actual area of column (in^2)
A-req-2 = Required area of column (in^2)
C-length-2 = Column length (in)
E-c = Modulus of elasticity of the column material (psi)
Fa-2 = Allowable compressive stress per API-650 5.10.3.4 (psi)
Fy-c = Allowable design stress (psi)
Max-P-column-2 = Maximum Load allowed for each column in ring (psi)
Max-T1-column-2 = Due to roof thickness (psf)
P-c-2 = Total roof load supported by each column (lbf)
P-ext-3-2 = Vacuum limited by column type (psf)
Pa-column-3-2 = Vacuum limited by column type (psi)
Pa-column-3-2 = Vacuum limited by column type (psi)
Radius-Gyr-2 = Radius of gyration
Radius-Gyr-req-2 = Radius of gyration required
W-column-2 = Total weight of column (lbf)
W-Max-column-2 = Maximum weight allowed for each column in ring (lbf)
Wi-2 = Load due to inner rafters and roof (lbf)
Wo-2 = Load due to outer rafters and roof (lbf)
W1-2 = Total rafter and roof load per girder length (lbf/in)
W-girder-2 = Total load including weight of girder (lbf/in)
AT GIRDER RING OUTER Radius = 75.25 ft
W-column-2 = 1,640.1602 lbf
Fy-c = 35,000 psi
E-c = 28,600,000.38 psi
A-actual-2 = 11.9083 in^2
C-length-2 = 40.4587 ft
Radius-Gyr-2 = 3.6717 in
If C-length-2/Radius-Gyr-2 must be less than 180, then
Radius-Gyr-req-2 = C-length-2/180
Radius-Gyr-req-2 = 40.4587/180
Radius-Gyr-req-2 = 2.6972 in
Per API-650 5.10.3.3
R-c-2 = C-length-2/Radius-Gyr-2
R-c-2 = 40.4587/3.6717
R-c-2 = 132.2306
Rafter-L-2 = (- R-2 - R-Inner2)/COS(Theta)
Rafter-L-2 = (- 898.8625 - 408.7058)/COS(3.5763)
Rafter-L-2 = 491.1131 in
Wi-2 = W-rafter-previous-2 * Max-r-span/2-previous-2 * (Num-of-Rafters-Previous-2 / Number-of-columns)
Wi-2 = 9.2357 * 226.5 * (40 / 8)
Wi-2 = 10,390.1988 lbf
C2-2 = [(Radial-distance-next - Radial-distance-actual) / 2] * Num-Gird-Req-actual-2
C2-2 = [(900.0 - 450.0) / 2] * 10
C2-2 = 2250 in
Wo-2 = W-rafter-actual-2 * C2-2
Wo-2 = 13.2954 * 2250 Wo-2 = 29,914.7288 lbf
W1-2 = (Wi-2 + Wo-2)/Girder-Length-2
W1-2 = (10,390.1988 + 29,914.7288)/344.4151
W1-2 = 117.0242 lbf/in
W-girder-2 = W1-2 + Girder-W-2
W-girder-2 = 117.0242 + 4.1666
W-girder-2 = 121.1909 lbf/in
P-c-2 = W-column-2 + (W-girder-2 * Girder-Length-2)
P-c-2 = 1,640.1602 + (121.1909 * 344.4151)
Since R-c-2 > 120, using API-650 Formulas in 5.10.3.4
Fa-2 = (/ (* 12 (EXPT PI 2) E-c) (* 23 (EXPT R-c-2 2)))
Fa-2 = (/ (* 12 (EXPT PI 2) 28,600,000.38) (* 23 (EXPT 132.2306 2)))
Per API-650 M.3.5
Fa is not modified Since Design Temp. <= 200 ºF.
(API-650 M.3.5 N.A.)
Fa-2 = 8,971.4086 psi
A-req-2 = P-c-2/Fa-2
A-req-2 = 43,380.1508/8,971.4086
A-req-2 = 4.8354 in^2
W-Max-column-2 = (Fa-2 * A-actual-2) - W-column-2
W-Max-column-2 = (8,971.4086 * 11.9083) - 1,640.1602
W-Max-column-2 = 105,193.9348 lbf
Max-P-column-2 = ((W-Max-column-2/((Rafter-L-2 * N-actual-2)/2)) - Rafter-Weight-2)/(AVERAGE Average-r-s-inner-2 , Average-r-s-shell-2)
Max-P-column-2 = ((105,193.9348/((491.1131 * 80)/2)) - 22)/(AVERAGE 2.675 , 5.883)
Max-P-column-2 = 0.5005 psi
Max-T1-column-2 = Max-P-column-2
Max-T1-column-2 = 72.072 psf
P-ext-3-2 = Max-T1-column-2 - DL - (Fp * MAX(S , Lr))
P-ext-3-2 = 72.072 - 7.6779 - (0.4 * MAX(0 , 20))
P-ext-3-2 = -56.3917 psf
Pa-column-3-2 = P-ext-3-2
Pa-column-3-2 = -56.3917 psf
Limited by column type
BAY 1 DETAILS
MINIMUM # OF RAFTERS
l = Maximum rafter spacing per API-650 5.10.4.4 (in)
l-actual-1 = Actual rafter spacing (in)
Max-T1-1 = Due to roof thickness (psf) N-actual-1 = Actual number of rafter
N-min-1 = Minimum number of rafter
P = Uniform pressure as determined from load combinations described in Appendix R (psi)
P-ext-1-1 = Due to roof thickness vacuum limited by actual rafter spacing (psf)
R-1 = Outer radius (in)
RLoad-Max-1 = Maximun roof load based on actual rafter spacing (psf)
t-calc-1 = Minimum roof thickness based on actual rafter spacing (in)
FOR GIRDER RING OUTER Radius = 37.5 ft
P = Lr-1
P = 0.2162 psi
R-1 = 450 in
l = MIN(((t-Roof - CA-Roof) * SQRT((1.5 * Fy-Roof)/P)) , 84)
l = MIN(((0.1875 - 0) * SQRT((1.5 * 36,000) / 0.2162)) , 84)
l = MIN(93.705 , 84)
l = 84 in
N-min-1 = (2 * PI * R-1)/l
N-min-1 = (2 * PI * 450)/84
N-min-1 = 34
N-min-1 must be a multiple of 8, therefore N-min-1 = 40.
N-actual-1 = 40
l-actual-1 = (2 * PI * R-1)/N-actual-1
l-actual-1 = (2 * PI * 450)/40
l-actual-1 = 70.6858 in
Minimum roof thickness based on actual rafter spacing
t-calc-1 = l-actual-1/SQRT((1.5 * Fy-Roof)/P) + CA-Roof
t-calc-1 = 70.6858/SQRT((1.5 * 36,000)/0.2162) + 0
t-calc-1 = 0.1414 in
NOTE: Governs for roof plate thickness.
RLoad-Max-1 = (1.5 * Fy-Roof)/(l-actual-1/(t-Roof - CA-Roof))^2
RLoad-Max-1 = (1.5 * 36,000)/(70.6858/(0.1875 - 0))^2
RLoad-Max-1 = 54.7134 psf
Max-T1-1 = RLoad-Max-1
Max-T1-1 = 54.7134 psf
P-ext-1-1 = Max-T1-1 - DL - (0.4 * MAX(Sb , Lr))
P-ext-1-1 = 54.7134 - 7.6779 - (0.4 * MAX(0 , 20))
P-ext-1-1 = -39.0356 psf
Pa-rafter-3-1 = P-ext-1-1
Pa-rafter-3-1 = -39.0356 psf
t-required-1 = MAX(0.1414 , (0.1875 + 0))
t-required-1 = 0.1875 in
RAFTER DESIGN
Average-p-width-1 = Average plate width (ft)
Average-r-s-inner-1 = Average rafter spacing on inner girder (ft)
Average-r-s-shell-1 = Average rafter spacing on shell (ft)
Max-P-1 = Load allowed for each rafter in ring (psi)
Max-r-span-1 = Maximum rafter span (ft)
Max-T1-rafter-1 = Due to roof thickness (psf) Mmax-rafter-1 = Maximum moment bending (in-lbf)
P-ext-2-1 = Vacuum limited by rafter type (psf)
R-1 = Outer radius (in)
R-Inner-1 = Inner radius (ft)
Rafter-Weight-1 = (lb/ft)
Sx-rafter-actual-1 = Actual elastic section modulus about the x axis (in^3)
Sx-rafter-Req'd-1 = Required elastic section modulus about the x axis (in^3)
Theta = Angle of cone to the horizontal (degrees)
W-Max-rafter-1 = Maximum stress allowed for each rafter in ring (lbf/in)
W-rafter-1 = (lbf/in)
SPAN TO GIRDER RING OUTER Radius = 37.75 ft
P = 0.2162 psi
Rafter-Weight-1 = 12 lbf/ft
Theta = 3.5763 degrees
R-1 = 453 in
R-Inner1 = 32 in
Max-r-span-1 = (R-1 - R-Inner-1)/COS(Theta)
Max-r-span-1 = (453 - 32)/COS(3.5763)
Max-r-span-1 = 35.2765 ft
Average-r-s-inner-1 = (2 * PI * R-Inner-1)/N-actual-1
Average-r-s-inner-1 = (2 * PI * 32)/40
Average-r-s-inner-1 = 0.4189 ft
Average-r-s-shell-1 = (2 * PI * R-1)/N-actual-1
Average-r-s-shell-1 = (2 * PI * 453)/40
Average-r-s-shell-1 = 5.9298 ft
Average-p-width-1 = (Average-r-s-inner-1 + Average-r-s-shell-1)/2
Average-p-width-1 = (0.4189 + 5.9298)/2
Average-p-width-1 = 3.1743 ft
W-rafter-1 = (P * Average-p-width-1) + Rafter-Weight-1
W-rafter-1 = (0.2162 * 38.0916) + 1
W-rafter-1 = 9.2357 lbf/in
Mmax-rafter-1 = (W-rafter-1 * Max-r-span-1^2)/8
Mmax-rafter-1 = (9.2357 * 423.318^2)/8
Mmax-rafter-1 = 206,879 in-lbf
Sx-rafter-Req'd-1 = Mmax-rafter-1/Sd
Sx-rafter-Req'd-1 = 206,879/23,200
Sx-rafter-Req'd-1 = 8.9172 in^3
Sx-actual-1 = 10.9 in^3
W-Max-rafter-1 = (Sx-rafter-actual-1 * Sd * 8)/Max-r-span-1^2)
W-Max-rafter-1 = (10.9 * 23,200 * 8)/423.318^2)
W-Max-rafter-1 = 11.2893 lbf/in
Max-P-1 = (W-Max-rafter-1 - Rafter-Weight-1)/Average-p-width-1
Max-P-1 = 0.2701 psi
Max-T1-rafter-1 = Max-P-1
P-ext-2-1 = Max-T1-rafter-1 - DL - (Fp * MAX(S , Lr))
P-ext-2-1 = 38.8944 - 7.6779 - (0.4 * MAX(0 , 20))
P-ext-2-1 = -23.2195 psf
P2-rafter-3-1 = P-ext-2-1
P2-rafter-3-1 = -23.2195 psf
Limited by rafter type
GIRDER DESIGN
NOT REQUIRED FOR CENTER COLUMN
CENTER COLUMN
A-actual-1 = Actual area of column (in^2)
A-req-1 = Required area of column (in^2)
C-length-1 = Column length (in)
E-c = Modulus of elasticity of the column material (psi)
Fa-1 = Allowable compressive stress per API-650 5.10.3.4 (psi)
Fy-c = Allowable design stress (psi)
Max-P-column-1 = Maximum Load allowed for each column in ring (psi)
Max-T1-column-1 = Due to roof thickness (psf)
P-c-1 = Total roof load supported by each column (lbf)
P-ext-3-1 = Vacuum limited by column type (psf)
Pa-column-3-1 = Vacuum limited by column type (psi)
Pa-column-3-1 = Vacuum limited by column type (psi)
R-c-1 = Per API-650 5.10.3.3
Radius-Gyr-1 = Radius of gyration
Radius-Gyr-req-1 = Radius of gyration required
W-column-1 = Total weight of column (lbf)
W-Max-column-1 = Maximum weight allowed for each column in ring (lbf)
W-column-1 = 1,770.1605 lbf
Fy-c = 35,000 psi
E-c = 28,600,000.38 psi
A-actual-1 = 11.9083 in^2
C-length-1 = 43.6853 ft
Radius-Gyr-1 = 3.6717 in
If C-length-1/Radius-Gyr-1 must be less than 180, then
Radius-Gyr-req-1 = C-length-1/180
Radius-Gyr-req-1 = 43.6853/180
Radius-Gyr-req-1 = 2.9124 in
Per API-650 5.10.3.3
R-c-1 = C-length-1/Radius-Gyr-1
R-c-1 = 43.6853/3.6717
R-c-1 = 142.776
Rafter-L-1 = (- R-1 - R-Inner1)/COS(Theta)
Rafter-L-1 = (- 450 - 0)/COS(3.5763)
Rafter-L-1 = 423.3185 in
P-c-1 = W-column-1 + (Rafter-L-1 * W-rafter-1 * N-actual-1)/2
P-c-1 = 1,770.1605 + (423.3185 * 9.2357 * 40)/2
P-c-1 = 79,963.2946 lbf
Since R-c-1 > 120, using API-650 Formulas in 5.10.3.4
Fa-1 = (/ (* 12 (EXPT PI 2) E-c) (* 23 (EXPT R-c-1 2)))
Fa-1 = (/ (* 12 (EXPT PI 2) 28,600,000.38) (* 23 (EXPT 142.776 2)))
Per API-650 M.3.5
Fa is not modified Since Design Temp. <= 200 ºF.
(API-650 M.3.5 N.A.)
Fa-1 = 8,152.9746 psi
A-req-1 = P-c-1/Fa-1
A-req-1 = 79,963.2946/8,152.9746
A-req-1 = 9.8079 in^2
W-Max-column-1 = (Fa-1 * A-actual-1) - W-column-1
W-Max-column-1 = (8,152.9746 * 11.9083) - 1,770.1605
W-Max-column-1 = 95,317.7892 lbf
Max-P-column-1 = ((W-Max-column-1/((Rafter-L-1 * N-actual-1)/2)) - Rafter-Weight-1)/(AVERAGE Average-r-s-inner-1 , Average-r-s-shell-1)
Max-P-column-1 = ((95,317.7892/((423.3185 * 40)/2)) - 12)/(AVERAGE 0 , 5.8905)
Max-P-column-1 = 0.2693 psi
Max-T1-column-1 = Max-P-column-1
Max-T1-column-1 = 38.7792 psf
P-ext-3-1 = Max-T1-column-1 - DL - (Fp * MAX(S , Lr))
P-ext-3-1 = 38.7792 - 7.6779 - (0.4 * MAX(0 , 20))
P-ext-3-1 = -23.1024 psf
Pa-column-3-1 = P-ext-3-1
Pa-column-3-1 = -23.1024 psf
Limited by column type
P-max-ext-T = MAX(P-ext-1-1 , P-ext-2-1 , P-ext-3-1 , P-ext-1-2 , P-ext-2-2 , P-ext-3-2)
P-max-ext-T = MAX(-39.0356 , -23.2195 , -23.1024 , -39.1741 , -27.8345 , -56.3917)
P-max-ext-T = -0.1604 psi or -23.1024 psf
Warning!!
1.- Please revise the Structure, there is a problem in the sizes.
TOP MEMBER DESIGN
CA_roof (Thickness of roof plate) = 0 in CA_shell (Thickness of shell plate) = 0 in D (Shell nominal diameter) = 150.0625 ft
ID (Shell inside diameter) = 150.0 ft
Theta angle (Angle between the roof and a horizontal plane at the roof-to-shell junction) = 3.5763 deg tc (Thickness of shell plate) = 0.3125 in
th (Thickness of roof plate) = 0.1875 in
Shell inside radius
Rc = ID / 2 = 1800.0 / 2 = 900.0 in Shell nominal diameter (D) = 150.0625 ft
Length of normal to roof
R2 = Rc / SIN(Theta angle) = 900.0 / SIN(3.5763) = 14428.0976 in
Thickness of corroded roof plate
th_corroded = th - CA_roof = 0.1875 - 0 = 0.1875 in
Thickness of corroded shell plate
tc_corroded = tc - CA_shell = 0.3125 - 0 = 0.3125 in
Maximum width of participating roof API-650 Figure F-2
Wh = MIN((0.3 * SQRT((R2 * th_corroded))) , 12) = MIN((0.3 * SQRT((14428.0976 * 0.1875))) , 12) = 12 in
Maximum width of participating shell API-650 Figure F-2
Wc = 0.6 * SQRT((Rc * tc_corroded)) = 0.6 * SQRT((900.0 * 0.3125)) = 10.0623 in
Nominal weight of shell plates and framing
DLS = Ws + W_framing = 344435.3687 + 59409.7227 = 403845.0914 lbf
Nominal weight of roof plates and attached structural
DLR = Wr + W_structural = 135679.1475 + 677.7268 = 136356.8743 lbf
Compression Ring Detail d Properties
ID (Shell inside diameter) = 150.0 ft Size (Compression ring size) = l3x3x3/8 Wc (Length of contributing shell) = 10.0623 in Wh (Length of contributing roof) = 12 in tc (Thickness of shell plate) = 0.3125 in th (Thickness of roof plate) = 0.1875 in Angle vertical leg size (l_vert) = 3.0 in Angle horizontal leg size (l_horz) = 3.0 in Angle thickness (t_angle) = 0.375 in Angle area (A_angle) = 2.11 in^2 Angle centroid (c_angle) = 0.884 in
Angle moment of inertia (I_angle) = 1.75 in^4
Length of contributing shell reduced
wc_reduced = Wc - l_vert = 10.0623 - 3.0 = 7.0623 in
Contributing shell moment of inertia
I_shell = (wc_reduced * (tc_corroded^3)) / 12 = (7.0623 * (0.3125^3)) / 12
= 0.018 in^4
Contributing shell area
Contributing roof area
A_roof = Wh * th_corroded = 12 * 0.1875 = 2.25 in^2
Detail total area
A_detail = A_shell + A_roof + A_angle = 2.207 + 2.25 + 2.11 = 6.567 in^2
Find combined moment of inertia about shell inside axis with negative value toward center
Description Variable
Equation
Value Unit
Shell centroid
d_shell
tc_corroded / 2
0.1563 in
Stiffener centroid
d_stiff
(the-reference (current-object) '(superior
angle-centroid) t t t nil 'default-the-error
nil)
0.8840 in
moment of inertia of
first body
I_1
I_angle + (A_angle * (d_stiff^2))
3.3989 in^4
moment of inertia of
second body
I_2
I_shell + (A_shell * (d_shell^2))
0.0718 in^4
Total area
A_sum
A_angle + A_shell
4.3170 in^2
Sum of moments of
inertia's
I_sum
I_1 + I_2
3.4707 in^4
Combined centroid
c_combined
((d_stiff * A_angle) + (d_shell * A_shell))
/ (A_angle + A_shell)
0.5120 in
Combined moment of
inertia
I_combined I_sum - (A_sum * (c_combined^2))
2.3393 in^4
Distance from neutral
axis to edge 1 (inside)
e1 l_horz
-
c_combined
2.4880 in
Distance from neutral
axis to edge 2 (outside)
e2 l_horz
-
e1
0.5120 in
Combined stiffener
shell section modulus
S
I_combined / MAX(e1 , e2)
0.9402 in^3
Roof Design Requirements
Appendix F Requirements
A_actual (Area resisting compressive force) = 6.567 in^2 D (Tank nominal diameter) = 150.0625 ft
DLR (Nominal weight of roof plates and attached structural) = 136356.8743 lbf DLS (Nominal weight of shell plates and framing) = 403845.0914 lbf
Fy (Minimum specified yield-strength of the materials in the roof-to-shell junction) = 36000 psi ID (Tank inside diameter) = 150.0 ft
Mw (Wind moment) = 6.6057000203E6 ft.lbf P (Design pressure) = 0.1 psi
Theta angle (Angle between the roof and a horizontal plane at the roof-to-shell junction) = 3.5763 deg W_framing (Weight of framing supported by the shell and roof) = 59409.7227 lbf
W_structural (Weight of roof attached structural) = 677.7268 lbf Wr (Roof plates weight) = 135679.1475 lbf
Uplift due to internal pressure API-650 F.1.2
P_uplift = P * pi * ((ID^2) / 4) = 0.1 * pi * ((1800.0^2) / 4) = 254469.0049 lbf
Weight of roof shell and attached-framing
W_total = Wr + Ws + W_framing
= 135679.1475 + 344435.3687 + 59409.7227 = 539524.2389 lbf
Net uplift due to internal pressure
Net_uplift = MAX((P_uplift - W_total) , 0)
= MAX((254469.0049 - 539524.2389) , 0) = 0 lbf
Wr < P_uplift <= W_total , Tank design should meet F.2 to F.6 requirements.
Maximum design pressure API 650 F.4.1
P_F41 = ((0.962 * A_actual * Fy * TAN(Theta angle)) / (D^2)) + ((0.245 * DLR) / (D^2)) = ((0.962 * 6.567 * 36000 * TAN(3.5763)) / (150.0625^2)) + ((0.245 * 136356.8743) / (150.0625^2))
= 2.1148 inH2O
Maximum design pressure for unanchored tank API 650 F.4.2
P_F42 = (((0.1632 * DLS) / (D^2)) + ((0.245 * DLR) / (D^2))) - ((0.2938 * Mw) / (D^3))
= (((0.1632 * 403845.0914) / (150.0625^2)) + ((0.245 * 136356.8743) / (150.0625^2))) - ((0.2938 * 6.6057000203E6) / (150.0625^3))
= 3.836 inH2O
Maximum design pressure
P_max = MIN(P_F41 , P_F42) = MIN(2.1148 , 3.836) = 2.1148 inH2O P > P_max ==> Design pressure is greater that maximum allowable pressure
*** WARNING *** : Design pressure is greater that maximum allowable pressure
Required area API 650 F.5.1
A_F51 = ((D^2) * (P - ((0.245 * DLR) / (D^2)))) / (0.962 * Fy * TAN(Theta angle))
= ((150.0625^2) * (2.7682 - ((0.245 * 136356.8743) / (150.0625^2)))) / (0.962 * 36000 * TAN(3.5763))
= 13.3657 in^2
A_actual < A_F51 ==> Compression region actual cross sectional area is not sufficient.
*** WARNING *** : Reinforcement needed due to insufficient cross sectional area. As per API-650 5.2.1 c), Maximum design internal pressure (P_std) = 2.5 psi
Maximum allowable internal pressure for the actual resisting area API 650 F.5.1
P_F51 = ((0.962 * Fy * TAN(Theta angle) * A_actual) / (D^2)) + ((0.245 * DLR) / (D^2)) = ((0.962 * 36000 * TAN(3.5763) * 6.567) / (150.0625^2)) + ((0.245 * 136356.8743) / (150.0625^2))
= 2.1148 inH2O
Maximum allowable internal pressure
P_max_internal = MIN(P_std , P_F51 , P_max) = MIN(2.5 , 0.0764 , 0.0764)
= 0.0764 psi
A_resisting (Detail resisting area) = 6.567 in^2 D (Nominal Tank Diameter) = 150.0625 ft
E (Modulus of Elasticity of Roof Plate Material) = 2.879999924E7 lb/in^2 H (Shell Height) = 40 ft
I_combined (Combined stiffener shell moment of inertia) = 2.3393 in^4 N (Waves Quantity) = 10.0
P (Total design external pressure for design of shell) = 37.0932 psf Pr (Total design external pressure for design of roof) = 31.1339 lb/ft^2 f (Smallest Allowable Tensile Stress) = 23200 psi
Radial Load Imposed on End Stiffener by Shell API 650 Section V.8.2.3.1
V1 = (Ps * H) / 48 = (37.0932 * 40) / 48 = 30.911 lb/in
End Stiffener Region Required Moment of Inertia API 650 Section V.8.2.3.2
Ireqd = (684 * V1 * (D^3)) / (E * ((N^2) - 1))
= (684 * 30.911 * (150.0625^3)) / (2.879999924E7 * ((10.0^2) - 1)) = 25.0586 in^4
I_combined < Ireqd ==> Combined stiffener shell moment of inertia is not sufficient.
*** WARNING *** : Reinforcement needed due to insufficient combined stiffener shell moment of inertia.
End Stiffener Region Required Cross Sectional Area API 650 Section V.8.2.3.3.1
Areqd = (6 * V1 * D) / f = (6 * 30.911 * 150.0625) / 23200.0 = 1.1996 in^2
Top stiffener required cross sectional area
A_stiff = (Areqd) = (1.1996) = 1.1996 in^2
A_resisting >= A_stiff ==> Compression region actual cross sectional area is sufficient.
Warning!!
1.- Design pressure is greater that maximum allowable pressure 2.- Reinforcement needed due to insufficient cross sectional area.
3.- Reinforcement needed due to insufficient combined stiffener shell moment of inertia.
SUMMARY OF ROOF RESULTS
Back
Material = A36
Structural Material = A36
t-actual = 0.1875 in
t-required = 0.1875 in
t-calc = 0.1875 in
P-Max-Internal = 0.0764 psi
P-Max-External = -0.1604 psi
Roof Plates Weight = 135,679.1475 lbf
Weight of Rafters = 88,962.6649 lbf
Weight of Girders = 11,480.5029 lbf
SHELL COURSE DESIGN (Bottom course is #1)
Back
API-650 ONE FOOT METHOD
D = Tank Nominal diameter (ft) per API-650 5.6.1.1 Note 1
H = Max liquid level (ft)
I-p = Design internal pressure (psi)
L = Factor
I-p = 0.1 psi
D = 150 ft
H = 40 ft
L = (6 * D (t-1 - Ca-1))^0.5
L = (6 * 150 (0.75 - 0))^0.5 = 25.9808
Course # 1
Ca-1 = Corrosion allowance per API-650 5.3.2 (in)
G = Design specific gravity of the liquid to be stored
H' = Effective liquid head at design pressure (ft)
hmax-1 = Max liquid level based on shell thickness (ft)
JE = Joint efficiency
pmax-1 = Max pressure at design (psi)
pmax-int-shell-1 = Max internal pressure at design (psi)
Sd = Allowable design stress for the design condition per API-650 Table 5-2a (psi)
St = Allowable stress for the hydrostatic test condition per API-650 5.6.2.2 (psi)
t-1 = Shell actual thickness (in)
t-calc-1 = Shell thickness design condition td (in)
t-seismic-1 = See E.6.2.4 table in SEISMIC calculations.
t-test-1 = Shell thickness hydrostatic test condition (in)
Material = A36
Width = 8 ft
Ca-1 = 0 in
JE = 1 t-1 = 0.75 in
Sd = 23,200 psi
St = 24,900 psi
Design Condition G = 1 (per API-650)
H' = H
H' = 40
H' = 40 ft
t-calc-1 = (2.6 * D * (H' - 1) * G)/Sd + Ca-1 (per API-650 5.6.3.2)
t-calc-1 = (2.6 * 150 * (40 - 1) * 1)/23,200 + 0
t-calc-1 = 0.6556 in
hmax-1 = Sd * (t-1 - CA-1)/(2.6 * D * G) + 1
hmax-1 = 23,200 * (0.75 - 0)/(2.6 * 150 * 1) + 1
hmax-1 = 45.6154 ft
pmax-1 = (hmax-1 - H) * 0.433 * G
pmax-1 = (45.6154 - 40) * 0.433 * 1
pmax-1 = 2.4315 psi
pmax-int-shell-1 = pmax-1
pmax-int-shell-1 = 2.4315 psi
Hydrostatic Test Condition G = 1
H' = H
H' = 40
H' = 40 ft
t-test-1 = (2.6 * D * (H' - 1))/St
t-test-1 = (2.6 * 150 * (40 - 1))/24,900
t-test-1 = 0.6108 in
Course # 2
Ca-2 = Corrosion allowance per API-650 5.3.2 (in)
G = Design specific gravity of the liquid to be stored
H' = Effective liquid head at design pressure (ft)
hmax-2 = Max liquid level based on shell thickness (ft)
JE = Joint efficiency
pmax-2 = Max pressure at design (psi)
pmax-int-shell-2 = Max internal pressure at design (psi)
Sd = Allowable design stress for the design condition per API-650 Table 5-2a (psi)
St = Allowable stress for the hydrostatic test condition per API-650 5.6.2.2 (psi)
t-2 = Shell actual thickness (in)
t-calc-2 = Shell thickness design condition td (in)
t-seismic-2 = See E.6.2.4 table in SEISMIC calculations.
t-test-2 = Shell thickness hydrostatic test condition (in)
Material = A36
Width = 8 ft
Ca-2 = 0 in
JE = 1 t-2 = 0.5625 in
Sd = 23,200 psi
St = 24,900 psi
Design Condition G = 1 (per API-650)
H' = H
H' = 32
H' = 32 ft
t-calc-2 = (2.6 * D * (H' - 1) * G)/Sd + Ca-2 (per API-650 5.6.3.2)
t-calc-2 = (2.6 * 150 * (32 - 1) * 1)/23,200 + 0
t-calc-2 = 0.5211 in
hmax-2 = Sd * (t-2 - CA-2)/(2.6 * D * G) + 1
hmax-2 = 23,200 * (0.5625 - 0)/(2.6 * 150 * 1) + 1
hmax-2 = 34.4615 ft
pmax-2 = (hmax-2 - H) * 0.433 * G
pmax-2 = (34.4615 - 32) * 0.433 * 1
pmax-2 = 1.0658 psi
pmax-int-shell-2 = MIN(pmax-int-shell-1 pmax-2)
pmax-int-shell-2 = MIN(2.4315 1.0658)
Hydrostatic Test Condition G = 1
H' = H
H' = 32
H' = 32 ft
t-test-2 = (2.6 * D * (H' - 1))/St
t-test-2 = (2.6 * 150 * (32 - 1))/24,900
t-test-2 = 0.4855 in
Course # 3
Ca-3 = Corrosion allowance per API-650 5.3.2 (in)
G = Design specific gravity of the liquid to be stored
H' = Effective liquid head at design pressure (ft)
hmax-3 = Max liquid level based on shell thickness (ft)
JE = Joint efficiency
pmax-3 = Max pressure at design (psi)
pmax-int-shell-3 = Max internal pressure at design (psi)
Sd = Allowable design stress for the design condition per API-650 Table 5-2a (psi)
St = Allowable stress for the hydrostatic test condition per API-650 5.6.2.2 (psi)
t-3 = Shell actual thickness (in)
t-calc-3 = Shell thickness design condition td (in)
t-seismic-3 = See E.6.2.4 table in SEISMIC calculations.
t-test-3 = Shell thickness hydrostatic test condition (in)
Material = A36
Width = 8 ft
Ca-3 = 0 in
JE = 1 t-3 = 0.3125 in
Sd = 23,200 psi
St = 24,900 psi
Design Condition G = 1 (per API-650)
H' = H
H' = 24
H' = 24 ft
t-calc-3 = (2.6 * D * (H' - 1) * G)/Sd + Ca-3 (per API-650 5.6.3.2)
t-calc-3 = (2.6 * 150 * (24 - 1) * 1)/23,200 + 0
t-calc-3 = 0.3866 in
hmax-3 = Sd * (t-3 - CA-3)/(2.6 * D * G) + 1
hmax-3 = 23,200 * (0.3125 - 0)/(2.6 * 150 * 1) + 1
hmax-3 = 19.5897 ft
pmax-3 = (hmax-3 - H) * 0.433 * G
pmax-3 = (19.5897 - 24) * 0.433 * 1
pmax-3 = -1.9096 psi
pmax-int-shell-3 = MIN(pmax-int-shell-2 pmax-3)
pmax-int-shell-3 = MIN(1.0658 -1.9096)
pmax-int-shell-3 = 0 psi (Since pmax-int-shell-3 < 0, pmax-int-shell-3 = 0 psi)
H' = H
H' = 24
H' = 24 ft
t-test-3 = (2.6 * D * (H' - 1))/St
t-test-3 = (2.6 * 150 * (24 - 1))/24,900
t-test-3 = 0.3602 in
Course # 4
Ca-4 = Corrosion allowance per API-650 5.3.2 (in)
G = Design specific gravity of the liquid to be stored
H' = Effective liquid head at design pressure (ft)
hmax-4 = Max liquid level based on shell thickness (ft)
JE = Joint efficiency
pmax-4 = Max pressure at design (psi)
pmax-int-shell-4 = Max internal pressure at design (psi)
Sd = Allowable design stress for the design condition per API-650 Table 5-2a (psi)
St = Allowable stress for the hydrostatic test condition per API-650 5.6.2.2 (psi)
t-4 = Shell actual thickness (in)
t-calc-4 = Shell thickness design condition td (in)
t-seismic-4 = See E.6.2.4 table in SEISMIC calculations.
t-test-4 = Shell thickness hydrostatic test condition (in)
Material = A36
Width = 8 ft
Ca-4 = 0 in
JE = 1 t-4 = 0.3125 in
Sd = 23,200 psi
St = 24,900 psi
Design Condition G = 1 (per API-650)
H' = H
H' = 16
H' = 16 ft
t-calc-4 = (2.6 * D * (H' - 1) * G)/Sd + Ca-4 (per API-650 5.6.3.2)
t-calc-4 = (2.6 * 150 * (16 - 1) * 1)/23,200 + 0
t-calc-4 = 0.2522 in
hmax-4 = Sd * (t-4 - CA-4)/(2.6 * D * G) + 1
hmax-4 = 23,200 * (0.3125 - 0)/(2.6 * 150 * 1) + 1
hmax-4 = 19.5897 ft
pmax-4 = (hmax-4 - H) * 0.433 * G
pmax-4 = (19.5897 - 16) * 0.433 * 1
pmax-4 = 1.5544 psi
pmax-int-shell-4 = MIN(pmax-int-shell-3 pmax-4)
pmax-int-shell-4 = MIN(0 1.5544)
pmax-int-shell-4 = 0 psi
Hydrostatic Test Condition G = 1
H' = H
H' = 16 ft
t-test-4 = (2.6 * D * (H' - 1))/St
t-test-4 = (2.6 * 150 * (16 - 1))/24,900
t-test-4 = 0.2349 in
Course # 5
Ca-5 = Corrosion allowance per API-650 5.3.2 (in)
G = Design specific gravity of the liquid to be stored
H' = Effective liquid head at design pressure (ft)
hmax-5 = Max liquid level based on shell thickness (ft)
JE = Joint efficiency
pmax-5 = Max pressure at design (psi)
pmax-int-shell-5 = Max internal pressure at design (psi)
Sd = Allowable design stress for the design condition per API-650 Table 5-2a (psi)
St = Allowable stress for the hydrostatic test condition per API-650 5.6.2.2 (psi)
t-5 = Shell actual thickness (in)
t-calc-5 = Shell thickness design condition td (in)
t-seismic-5 = See E.6.2.4 table in SEISMIC calculations.
t-test-5 = Shell thickness hydrostatic test condition (in)
Material = A36
Width = 7.75 ft
Ca-5 = 0 in
JE = 1 t-5 = 0.3125 in
Sd = 23,200 psi
St = 24,900 psi
Design Condition G = 1 (per API-650)
H' = H
H' = 8
H' = 8 ft
t-calc-5 = (2.6 * D * (H' - 1) * G)/Sd + Ca-5 (per API-650 5.6.3.2)
t-calc-5 = (2.6 * 150 * (8 - 1) * 1)/23,200 + 0
t-calc-5 = 0.1177 in
hmax-5 = Sd * (t-5 - CA-5)/(2.6 * D * G) + 1
hmax-5 = 23,200 * (0.3125 - 0)/(2.6 * 150 * 1) + 1
hmax-5 = 19.5897 ft
pmax-5 = (hmax-5 - H) * 0.433 * G
pmax-5 = (19.5897 - 8) * 0.433 * 1
pmax-5 = 5.0184 psi
pmax-int-shell-5 = MIN(pmax-int-shell-4 pmax-5)
pmax-int-shell-5 = MIN(0 5.0184)
pmax-int-shell-5 = 0 psi
Hydrostatic Test Condition G = 1
H' = H
H' = 8
t-test-5 = (2.6 * D * (H' - 1))/St
t-test-5 = (2.6 * 150 * (8 - 1))/24,900
t-test-5 = 0.1096 in
SUMMARY OF SHELL RESULTS
Back
t-min-Seismic = See API-650 E.6.1.4, table in SEISMIC calculations.
Shell API-650 Summary (Bottom is 1)
She ll # Widt h (in) Materi al C A (in ) J E Min Yield Strengt h (psi) Tensile Strengt h (psi) Sd (psi) St (psi) Weigh t (Lbf) Weigh t CA (Lbf) t-min Erectio n (in) t-Des (in) t-Test (in) t-min Seismi c (in) t-min Ext-Pe (in) t-min (in) t-Actu al (in) Statu s 1 96 A36 0 1 36,000 58,000 23,20 0 24,90 0 115,29 7 115,29 7 0.3125 0.655 6 0.610 8 0.5087 0.435 9 0.655 6 0.75 OK 2 96 A36 0 1 36,000 58,000 23,20 0 24,90 0 86,482 86,482 0.3125 0.521 1 0.485 5 0.4062 0.435 9 0.521 1 0.562 5 OK 3 96 A36 0 1 36,000 58,000 23,20 0 24,90 0 48,052 48,052 0.3125 0.386 6 0.360 2 0.3029 0.435 9 0.435 9 0.312 5 FAIL 4 96 A36 0 1 36,000 58,000 23,20 0 24,90 0 48,052 48,052 0.3125 0.252 2 0.234 9 0.199 0.435 9 0.435 9 0.312 5 FAIL 5 93 A36 0 1 36,000 58,000 23,20 0 24,90 0 46,550 46,550 0.3125 0.117 7 0.109 6 0.0948 0.435 9 0.435 9 0.312 5 FAIL Total Weight = 344,435.3686 Lbf
Warning!!
1.- Please revise the shell thk, 3 courses have problems.
2.- The required minimum thickness based on external pressure is greater than the available thickness and the shell must be stiffened.
API-650 APPENDIX V FOR EXTERNAL PRESSURE
V = Wind load velocity (mph)
W = Wind pressure (psf)
Pe = External Pressure (psi)
Ps = Shell design pressure (psf)
t-width = Shell ring actual width (ft)
t-course = Shell ring actual thickness (in)
t-uniform = as-built thickness, unless otherwise specified, of the thinnest shell course, (in)
Wtr = Transposed width of each shell course (ft)
Hts = Height of the transformed shell (ft)
V = 125 mph
Pe = 8.64 psf
W = 31 * (V/120)^2
W = 31 * (125/120)^2
W = 33.6372 psf
Ps = MAX(Pe , (W + (Fp * Pe)))
Ps = MAX(8.64 , (33.6372 + (0.4 * 8.64)))
Ps = 37.0932 psf
Hts = SUM(Wtr)
Transforming courses (1) to (5)
Wtr-1 = 8 * (0.3125 / 0.75)^2.5 = 0.8965 ft
Wtr-2 = 8 * (0.3125 / 0.5625)^2.5 = 1.8404 ft
Wtr-3 = 8 * (0.3125 / 0.3125)^2.5 = 8 ft
Wtr-4 = 8 * (0.3125 / 0.3125)^2.5 = 8 ft
Wtr-5 = 8 * (0.3125 / 0.3125)^2.5 = 8 ft
Hts = 26.7369 ft
INTERMEDIATE STIFFENER CALCULATIONS PER API-650 APP. V.8
A-reqd-(n) = Required area (in^2)
A-stiff-(n) = Area required by Stiffener (in^2)
A-stiff-actual-(n) = Actual area (in^2)
Bottom-OD = Bottom floor OD diameter per API-650 5.6.1.1 Note 1 (ft)
D = Nominal diameter per API-650 5.6.1.1 Note 1 (ft)
E = Modulus of elasticity of the roof plate material (psi)
EFC = Elastic failure
F-btm = Allowable stress for bottom floor (psi)
F-roof = Allowable stress for thinnest shell (psi)
F-stiff = Allowable stress for stiffener (psi)
Fc = Smallest allowable compressive stress (psi)
Fp = Pressure Combination Ratio
Fy-shell = Minimum yield strength for shell material (Table 5-2b) (psi)
Fy-stiff = Minimum yield strength for stiffener material (Table 5-2b) (psi)
Hs = Maximum unstiffened shell height (ft)
Hts = Height of the transformed shell (ft)
I-actual-(n) = Actual moment of inertia (in^4)
I-reqd-(n) = Required moment of inertia (in^4)
JEb = Bottom joint efficiency
JEn = Bottom shell course joint efficiency
JEr = Roof joint efficiency
JEs = Top shell course joint efficiency
Ls = Actual spacing (ft)
Lx = Maximum stiffener spacing on transposed shell (ft)
L_act = Actual Transform Height Spacing between Stiffeners (ft)
N = Number of waves
NS = Number of stiffeners required
NS-actual = Actual Number of stiffeners
Pe = External Pressure (psf)
Ps = Shell design pressure (psf)
Ps-Max = Maximum allowable external pressure for unstiffened shell (psf)
PSI-C = Stability factor
PSI1 = Stability factor under condition 1 (V.8.1)
PSI2 = Stability factor under condition 2 (V.8.1)
Pv-Max-1 = Maximum allowable external pressure for unstiffened shell under condition 1 (psf)
Pv-Max-2 = Maximum allowable external pressure for unstiffened shell under condition 2 (psf)
Pv-Max-C = Final maximum allowable external pressure for unstiffened shell (psi)
Q-(n) = Radial load imposed on intermediate stiffeners by the shell (lbf/ft)
t-min-ext = Minimum thickness due to design pressure (in) t-min-ext-stiff = Minimum thickness due to stiffener (in) ts-(n) = Actual shell course thickness (in)
ts1 = Top shell course thickness (in)
tsmin = Smallest actual shell course thickness (in) tsn = Bottom shell course thickness (in)
W-shell-(n) = Contributing shell at stiffener n (in)
W = 33.6372 psf
Hts = 26.7369 ft
Wtr-1 = t-width-(n) * (t-top/ts-(n))^2.5
Wtr = Hts = 26.7369 ft
Fp = 0.4
D = 150 ft
ts1 = 0.3125 in tsn = 0.75 in CA = 0 in tsmin = 0.3125 in JEr = 1
JEs = 1
F-roof = 23,200 psi
Fy-shell = 36,000 psi
E = 28,799,999 psi
F-stiff = 0 psi
Fy-stiff = 0 psi
F-btm = 23,200 psi
JEn = 1
JEb = 1
Bottom-OD = 145.7083 ft
V.8.1 UNSTIFFENED SHELLS
Pe = 8.64 psf
Ps = 37.0932 psf
V.8.1.1 Criteria (Elastic failure when EFC >= 0.19,
otherwise must use ASME section VIII Div 1.)
EFC = (D / tsmin)^0.75 * [(HtS / D) * (Fy-shell / E)^0.5]
EFC = (150 / 0.3125)^0.75 * [(26.7369 / 150) * (36,000 / 28,799,999)^0.5]
EFC = 0.6463
Since EFC >= 0.19 using App. V method.
Condition 1: Wind plus specified external (Vacuum) pressure
Since Pe > 5.2 & Pe <= 15, (Pe + 15)/20
PSI1 = (Pe + 15)/20
PSI1 = (8.64 + 15)/20
PSI1 = 1.182
V.8.1.2 Maximum external pressure
Ps-Max = (0.6 * E)/[PSI1 * (HtS/D) * (D/tsmin)^2.5]
Ps-Max = (0.6 * 28,799,999)/[1.182 * (26.7369/150) * (150/0.3125)^2.5]
Ps-Max = 16.2481 psf
Pv-Max-1 = MIN(Ps-Max , (Ps-Max - W)/Fp)
Pv-Max-1 = MIN(16.2481 , (16.2481 - 33.6372)/0.4)
Pv-Max-1 = -43.4726 psf or -0.3019 psi
Pv-Max-2 = (0.6 * E)/[PSI2 * (HTS/D) * (D/tsmin)^2.5]
Pv-Max-2 = (0.6 * 28,799,999)/[3 * (26.7369/150) * (150/0.3125)^2.5]
Pv-Max-C = MIN(Pv-Max-1 , Pv-Max-2)
Pv-Max-C = MIN(-43.4726 , 6.4018)
Pv-Max-C = -43.4726 psf or -0.3019 psi
Condition 2: Specified external (Vacuum) pressure only
PSI2 = 3
V.8.1.3 Minimum thickness due to design pressure
Since Pe < Ps
t-min-1-ext = (1.23 * (PSI1 * HTS * Ps)^0.4 * D^0.6) / E^0.4
t-min-1-ext = (1.23 * (1.182 * 26.7369 * 37.0932)^0.4 * 150^0.6) / 28,799,999^0.4 t-min-1-ext = 0.4359 in
t-min-2-ext = (1.23 * (PSI2 * HTS * Pe)^0.4 * D^0.6) / E^0.4
t-min-2-ext = (1.23 * (3 * 26.7369 * 8.64)^0.4 * 150^0.6) / 28,799,999^0.4 t-min-2-ext = 0.3533 in
t-min-ext = MAX(t-min-1-ext , t-min-2-ext)
t-min-ext = MAX(0.4359 , 0.3533)
t-min-ext = 0.4359
CIRCUMFERENTIALLY STIFFENED SHELLS
Since no Int. stiffener are specified,
L_act = Wrt
L_act = 26.7369 ft
Number of Intermediate Stiffeners NOT Sufficient Since Hsafe < L_act
Warning: Stiffener spacing is greater than permitted height of unstiffened shell
V.8.2.2.3 Radial load
Q = N.A., Since no Int. stiffeners are specified.
V.8.2.2.4 Contributing shell at stiffener
W-shell = N.A., Since no Int. stiffeners are specified.
SUMMARY OF SHELL STIFFENING RESULTS
Number of Intermediate stiffeners req'd (NS) = 2
Warning!!
FLAT BOTTOM: ANNULAR PLATE DESIGN
Back
Ann-a = Area of annular ring (in^2) Ann-d = Density of annular ring (lbf/in3)
Ann-t-actual = Actual annular ring thickness (in)
Ann-t-min = Minimum annular ring plates thickness per API-650 5.5.3 TABLE 5-1b (in)
Ann-w-actual = Actual annular ring width (in)
Ann-w-min = Minimum annular ring width per API-650 5.5.2 (in) Ba = Area of bottom (in^2)
Bottom-OD = Bottom diameter (ft)
ca-1 = Bottom (1st) shell course corrosion allowance ca-Ann = Annular ring corrosion allowance (in)
Ca-bottom = Bottom corrosion allowance (in)
D = Nominal diameter per API-650 5.6.1.1 Note 1 (ft)
D-bottom = Density of bottom (lbf/in3)
G = Design specific gravity of the liquid to be stored
H = Max liquid level (ft)
H' = Effective liquid head at design pressure (ft)
R = Nominal radius (ft)
S = Maximum Stress in first shell course per API 650 Table 5.1.b S1 = Product stress in the first shell course per API 650 Table 5.1.b
S2 = Hydrostatic test stress in the first shell course per API 650 Table 5.1.b
Sd = Allowable design stress for the design condition in bottom (1st) shell course (psi) per API 650 5.6.3.2
St = Allowable stress for the hydrostatic test condition in bottom (1st) shell course (psi) per API 650 5.6.3.2
t-1 = Bottom (1st) shell course thickness (in) t-actual = Actual bottom thickness (in)
t-calc = Minimum nominal bottom plates thickness per API-650 5.4.1 (in)
t-min = Minimum nominal bottom plates thickness per API-650 5.4.1 (in)
t-test-1 = Bottom (1st) shell course test thickness (in) td-1 = Bottom (1st) shell course design thickness (in) Material = A36
t-actual = 0.25 in
Annular Ring Material = A36
Ann-t-actual = 0.375 in
Ann-w-actual = 30 in
Calculation of Hydrostatic Test Stress & Product Stress (per API-650 Section 5.5.1)
Bottom-OD = 145.7083 ft
JE = 1
D-bottom = 0.283 lbf/in3
t-1 = 0.75 in
ca-1 = 0 in
G = 1
H = 40 ft
H' = 40 ft
St = 24,900 psi
Sd = 23,200 psi
Ca-bottom = 0 in
ca-Ann = 0 in
Ann-d = 0.2 lbf/in3
Product stress in first shell course
S1 = ((0.6556 - 0) / (0.75 - 0)) * 23,200
S1 = 20,280 psi
Hydrostatic test stress in first shell course
S2 = (t-test-1 / t-1) * St
S2 = (0.6108 / 0.75) * 24,900
S2 = 20,280 psi
S = Max (S1, S2)
S = Max (20,280 , 20,280)
S = 20,280 psi
API-650 Table 5.1b required thickness of annular ring excluding corrosion allowance is 0.236 in
Annular ring required thickness = 0.236 + ca-Ann = 0.236 + 0
Annular ring required thickness = 0.236 in
Weight of Bottom plate
BA = PI * ((Bottom-OD / 2) - Ann-w-actual)^2
BA = PI * ((1748.5 / 2) - 30)^2
BA = 2,239,195.4929 in^2
Ann-a = PI/4 * Bottom-OD^2 - BA
Ann-a = PI/4 * 1748.5^2 - 2,239,195.4929
Ann-a = 161,964.8092 in^2
weight = (D-bottom * t-actual * BA) + (Ann-d * Ann-t-actual * Ann-A)
weight = (0.283 * 0.25 * 2,239,195.4929) + (0.2 * 0.375 * 161,964.8092)
weight = 175,797.7572 lbf
API-650
t-min = 0.236 + Ca-bottom
t-min = 0.236 + 0
t-min = 0.236 in
t-calc = t-min
t-calc = 0.236 in
Per API 650 appendix V.9.1
P-btm = D-bottom * t-actual + P_liq_min
P-btm = 0.283 * 0.25 + 0.8669
P-btm = 0.9378 psi
ABS(E-p) < P-btm Then there is no uplift
API-650 5.5
Ann-t-min = 0.236 in
Ann-w-min = (390 * Ann-t-actual)/(H * G)^0.5
Ann-w-min = 24 in Note: API-650 until the inner radius of the shell.
Ann-w-min = 28.25 in Note: including chime distance, overlap and shell thickness.
SUMMARY OF BOTTOM RESULTS
Back
Material = A36
t-actual = 0.25 in
t-req = 0.236 in
Annular Ring Material = A36
Ann-t-actual = 0.375 in
Ann-w-actual = 30 in
Ann-t-min = 0.236 in
Ann-w-min = 28.25 in
NET UPLIFT DUE TO INTERNAL PRESSURE
Net-Uplift = 0 lbf, (See roof report for calculations)
WIND MOMENT (Per API-650 SECTION 5.11)
Back
A = Area resisting the compressive force, as illustrated in Figure F.1
P-F41 = Design pressure determined in F.4.1
P-v = Internal pressure
Wind Velocity per API-650 ASCE 7-05
V_entered = 125 mph I = 1
Vs (Wind Velocity) = SQRT(I) * V_entered = 125 mph
Vf = (Vs / 120)^2
Vf = (125 / 120)^2
Vf (Velocity Factor) = 1.0851
PWS = 18 * Vf
PWS = 19.5312 psf
PWR = 30 * Vf
PWR = 32.552 psf
API-650 5.2.1.k Uplift Check
P-F41 = (0.962 * A * Fy * TAN(Theta))/D^2 + (0.245 * DLR)/D^2
P-F41 = ((0.962 * 6.567 * 36,000 * TAN(3.5763))/150^2) + ((0.245 * 136357) / 150^2)
P-F41 = 0.0765 psi = 11.0098 psf
Wind-Uplift = MIN(PWR , (1.6 * P-F41 - Pv))
Wind-Uplift = MIN(32.552 , 3.2157)
Wind-Uplift = 3.2157 psf
Ap-Vert (Vertical Projected Area of Roof) = 351.5625 ft^2
Horizontal Projected Area of Roof (Per API-650 5.2.1.f)
Xw (Moment Arm of UPLIFT wind force on roof) = 75 ft