A steel storage tank 20 meters in diameter will be used to hold a liquid petroleum...

 

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A steel storage tank 20 meters in diameter will be used to hold a liquid petroleum product. When filled, the tank will apply a bearing pressure of 150 kPa to the ground surface. The soil underlying the tank is a 30-meter thick clay layer, and the water table is at the ground surface. The properties of the clay layer are: ysat = 18.5 kN/m³; OCR=1.4; e, = 0.5; Cr=0.05, Ce = 0.4. Using the Boussinesq stress distribution method for your calculations. a. Compute the initial effective vertical stress (o'vo), the preconsolidation pressure (o'p), and the final effective vertical stress (o'vt) below the center of the tank when the tank is full at the average depths shown below. Complete these calculations by dividing the clay layer into 5-meter thick sublayer increments. b. Plot o'vo, o'p, o'vf versus depth from your answers for Part (a). c. Calculate the total consolidation settlement for the entire clay layer by summing the sublayer consolidation settlements for each of the same 5-meter thick sublayers. (Hint: use the stresses that you computed in Part (a) for this calculation.) Depth (m) o'vo (kPa) o, (kPa) of (kPa) Sublayer depth increment (m) 0-5 2.5 5- 10 7.5 10 - 15 12.5 15 - 20 17.5 22.5 27.5 Total settlement (m) 20 – 25 25 – 30 A steel storage tank 20 meters in diameter will be used to hold a liquid petroleum product. When filled, the tank will apply a bearing pressure of 150 kPa to the ground surface. The soil underlying the tank is a 30-meter thick clay layer, and the water table is at the ground surface. The properties of the clay layer are: ysat = 18.5 kN/m³; OCR=1.4; e, = 0.5; Cr=0.05, Ce = 0.4. Using the Boussinesq stress distribution method for your calculations. a. Compute the initial effective vertical stress (o'vo), the preconsolidation pressure (o'p), and the final effective vertical stress (o'vt) below the center of the tank when the tank is full at the average depths shown below. Complete these calculations by dividing the clay layer into 5-meter thick sublayer increments. b. Plot o'vo, o'p, o'vf versus depth from your answers for Part (a). c. Calculate the total consolidation settlement for the entire clay layer by summing the sublayer consolidation settlements for each of the same 5-meter thick sublayers. (Hint: use the stresses that you computed in Part (a) for this calculation.) Depth (m) o'vo (kPa) o, (kPa) of (kPa) Sublayer depth increment (m) 0-5 2.5 5- 10 7.5 10 - 15 12.5 15 - 20 17.5 22.5 27.5 Total settlement (m) 20 – 25 25 – 30