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Job No.: Doc No.:Sheet 1 of 5

5-

5.1- LOADING DATA

Empty weight of Tank (WE) 3387.0 KNOperating weight of Tank (WT) 145805.0 KNSurcharge Load (DW1) 0.0 KN/m2

5.1.1- Wind LoadWind Load (Fw) 286.34 KNMoment by Wind (MW) 2094.60 KN-mIncreased Line Load by Wind (W1) 1.99 KN/m

5.1.2- Seismic LoadSeismic Force 12521.86 KNMoment by Earthquake Shell Pressure (MP) KN-mMoment by Earthquake Bottom Pressure (MPB) KN-mMoment by Earthquake (ME) 70057.92 KN-mIncreased Line Load by MP (T) KN/m

5.2- MATERIAL SPECIFICATIONS

5.2.1- StrengthReinforcement bar yield strength 420.0 MPaConcrete compressive strength at 28 days (Cylinder) 21.0 MPa

5.2.2- Unit WeightReinforced Concrete 24.0 kN/cu-mSoil 17.0 kN/cu-mSteel 78.4 kN/cu-mWater 9.81 kN/cu-m

5 3 SOIL CONDITION

CALCULATION FOR TANK FOUNDATION

5.3- SOIL CONDITION

5.3.1- Net Soil Bearing Capacity of AreaIn normal operations 150.0 kPaNormal operation + Lateral forces 200.0 kPa

5.3.2- Coefficient of Lateral Soil Pressure (As per geotechnical study) 30Active soil pressure coefficient Ka = tan (45 - /2) 0.33At rest soil pressure coefficient Ko = 1 - sin 0.50Passive soil pressure coefficient Kp = tan (45 + /2) 3.00Coefficient of friction = m = 0.58

5.4- EQUIPMENT DATA

Diameter of Tank 36.576 mHeight of Tank = H = 14.630 m

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Job No.: Doc No.:Sheet 2 of 5

5.5- FOUNDATION OUTLINE

Width of Pedestal (b) 0.400 mWidth of Footing (b2) 1.500 mHeight of Pedestal (h1) 1.500 mThickness of Footing (h2) 0.400 mSoil Cover (h3) 0.900 mOuter Dia of Footing (D0) 38.076 mInner Dia of Footing (Di) 35.076 m

5.5.1- Areas & Moment of InertiaArea of Foundation (A = p(D0

2-Di2)/4) 172.4 sq-m

Area of Soil enclosed by Ring (A1 = pDi2/4) 966.3 sq-m

Area enclosed by Tank (A3 = pD2/4) 1050.7 sq-m

Moment of Inertia of Ring = p(Do4-Di

4)/64 28871.5 m^4

b2

h

h2

h1

5.5.2- Loading at Bottom of Foundation

Weight of Pedestal 1654.7 KNWeight of Foundation 1654.7 KNWeight of Soil over slope 1933.9 KN% Load transferred to Ring (P1) 8.03 % = 11442 KN% Load transferred to Soil (P2) 91.97 % = 130976 KNMoment due to wind force (Fw) 544.0 KN-mTotal Wind Moment (MWt) 2638.6 KN-mMoment due to earthquake force (FE) 23791.5 KN-mTotal Earthquake Moment (Met) 93849.5 KN-m

Maximum pressure on soil enclosed by ring (P2/A1) 135.5 KN/ sq.mOK , SOIL IMPOSED PRESSURE < SOIL B.C

5.5.3- Maximum and minimum force on foundationPmax=WE +wt of footing + % Load transferred to Ring= 20072 KNPmin=WE + self wt of footing = 8630 KN

b2

h

h2

h1

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Job No.: Doc No.:Sheet 3 of 5

5.6- STABILITY CHECKS

5.6.1- CHECK FOR BEARING PRESSURE

5.6.1.1- Bearing Pressure for Full Load of Tank

Stress on ring when tank is full = s = Pmax/A = 116.5 KN/ sq.mOK , FOOTING IS SAFE

5.6.1.2- Seismic Load When Tank is Full

s max , min = P/A + M y/I + T where A=area of ring foundation. y =Dia of tank /2M = Overturning Moment I = Moment of Inertia. T= Increased Load Due to ME

Max Stress = smax = 178.3 KN/ sq.mOK , FOOTING IS SAFE

Min Stress = smin = 54.6 KN/ sq.mOK , FOOTING IS SAFE

5.6.1.3- Wind Load When Tank is Empty

s max , min = P/A + M y/I + W1 where W1=Increased Load due to Wind

Max Stress = smax = 53.1 KN/ sq.mOK , FOOTING IS SAFE

Min Stress = smin = 48.3 KN/ sq.mOK , FOOTING IS SAFE

5.6.2- CHECK AGAINST OVERTURNING

5.6.2.1- Seismic Load When Tank is Full

Overturning moment by Earthquake ME = MO = 70057.9 KN-mResisting Moment = MR = Full tank load x DO/2 = 2775835.6 KN-mFactor of safety =MR /Mo = 39.6

OK FOOTING IS SAFEOK , FOOTING IS SAFE5.6.2.2- Wind Load When Tank is Empty

Overturning Moment = Mo = 2094.6 KN-mResisting Moment = MR =Emp.tank load x DO/2 = 64481.7 KN-mFactor of safety =MR /Mo = 30.8

OK , FOOTING IS SAFE5.6.3- CHECK AGAINST SLIDING

5.6.3.1- Seismic Load When Tank is Full

Sliding Force = Lateral seismic force for full load = 12521.9 KNResisting Force = m x Full vertical load 84180.6 KNFactor of safety = Sliding force/Resisting force = 6.7

OK , FOOTING IS SAFE5.6.3.2- Wind Load When Tank is Empty

Sliding Force = Lateral wind force for empty tank = 286.3 KNResisting Force = m x vertical load of empty tank = 1955.5 KNFactor of safety = Sliding force/Resisting force = 6.8

OK , FOOTING IS SAFE

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Job No.: Doc No.:Sheet 4 of 5

5.7- DESIGN OF REINFORCEMENT

5.7.1- PEDESTAL DESIGN

5.7.1.1- CIRCUMFERENCIAL REINFORCEMENT

Density of soil 17.0 N/mm3

Surcharge load (DW1) 0.0 N/mm3

Depth of footing (h) 1.50 mActive earthpresure coefficient (Ka) 0.50Effective height ( h ' = DW1/ g soil ) 0 0 m

Surcharge Load DW1

h

P

y

Ka c (h + h')

TT

Hoop Tension

P

Effective height ( h = DW1/ g soil ) 0.0 m

Hoop Stress P = 1/2 Ka gsoil h ( h + 2 h ' ) 9.6 KN/m

Now tensile force 'T' in ring foundation due to hoop stresses and surcharge load is calculated as follows,Hoop force F = P x Di 335.4 KN

T = F/2 167.7 KNDesign force =1.4 T = 234.8 KN

Area of steel = T/fy 559 mmMinimum As = (r min =0.0025 , Ref ACI-318-02-14.3.3) 1500 mmRequired As = 1500 mm

Bar size (db) 20 mmSectional area 314 mmRequired No. of Bars 6

Provide 3 - D20 bars on each face Provide @200C/C

Surcharge Load DW1

h

P

y

Ka c (h + h')

TT

Hoop Tension

P

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Job No.: Doc No.:Sheet 5 of 5

5.7.1.2- VERTICAL REINFORCEMENT

Minimum As = (r min =0.0012 , Ref ACI-318-02-14.3.2) 480 mm/m

Bar size (db) 12 mmSectional area 113 mmRequired spacing of bars 236 mm

Provide D12 @ 200 mm c/c

5.7.2- FOOTING DESIGN

5.7.2.1- Minimum and Maximum Ratio of Reinforcementpa = fc' / 4 fy 0.0027pb = 1.4 / fy 0.0033p1 = Max ( pa, pb ) 0.0033pmax = 0.75 x 0.85 1 fc'/fy 600 / (600+ fy) 0.0159

p t & s = for temperature & shrinkage reinforcement 0.0018used with gross area of footingused with gross area of footing

Min As (by shrinkage and temperature reinforcement) 587 mm

5.7.2.2- Design of Rebar

178.3 kN/m b 1.000 mL 0.550 m d 0.326 mBar size (db) 16 mmSectional area 201 mm

M L / 2 26.97 kN-m/mRn Mu / ( b d) 0.395 Mpap req 0.85 fc' / fy (1 - (1 - 2 Rn / 0.85 fc')) 0.0010Calculated As 310 mmMin As 412 mmMax As 5196 mm

number of re-bar 10re bar pitch 150 mmTotal area (As) 2011 mm

Provide 10 - D16 bars (T &B) @ 150 mm c/c

CHECK FOR ADEQUACY FOR BASE SLAB THICKNESS

Assumed Thickness 400 mmAllowable Soil Pressure 150 Kn/m2

L' (Extented Portion of Concrete) 550 mm

Vu 82.1 KN/m

Allaowable concrete stress for 21Mpa =649kpaActual Shear Stress for wall per meter length

Va=Vu/Ld136.833333