3. (Modified version of Problem 5.39 in the text). An unconfined sand aquifer with a surface area of 10,000 m? experiences a 1 m water level drop. The porosity and specific yield for the sand aquifer are given as 0.34 and 0.25, respectively. a. Calculate the volume of water that would be released from the aquifer. m3 b. How much water would remain in the drained portion of the aquifer? m3

3. (Modified version of Problem 5.39 in the text). An unconfined sand aquifer with a surface area of 10,000 m? experiences a 1 m water level drop. The porosity and specific yield for the sand aquifer are given as 0.34 and 0.25, respectively. a. Calculate the volume of water that would be released from the aquifer. m3 b. How much water would remain in the drained portion of the aquifer? m3

Principles of Geotechnical Engineering (MindTap Course List)

9th Edition

ISBN:9781305970939

Author:Braja M. Das, Khaled Sobhan

Publisher:Braja M. Das, Khaled Sobhan

Chapter7: Permeability

Section: Chapter Questions

Problem 7.22P: Refer to Figure 7.24. The following data were collected during the field permeability measurement of...

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2. A confined aquifer is recharged by a continuous supply of water from the certain source. The average thickness of the aquifer was determined to be 25 m and the average width is 4 km. The hydraulic conductivity of the aquifer was obtained at 40 m/day and its void ratio is 0.3333. The piezometer heads in two wells 1.325 km apart are 65 meters and 60 meters from a common reference datum. Determine the rate of flow in cubic meters per day. Determine: •compute the rate of flow through the aquifer in m3/day •compute the seepage velocity in m/day •compute the time of travel from the head of the aquifer to a point 8 km downstream in days
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From the figure shown, an unconfined non homogenous aquifer between two water bodies at a depth of t1 = 96 m and t2 = 75 m respectively. Take K1 = 36 m/s, K2 = 48 m/s, H1 = 1470 m and H2 = 1230 m. K, K2 t2 H1 H2 a. Compute the average coefficient of permeability of the aquifer in m/s. (2 DECIMAL PLACES) b. Compute the rate of flow in m^3/s. (2 DECIMAL PLACES) c. Compute the time in seconds required for the water to pass through the soil if it has a void ratio of 0.36. (2 DECIMAL PLACES)
Q 1 .An aquifer has following different formations, their thickness and Hydraulic conductivity are given below. Assume that each formation is isotropic and homogeneous. Compute both the equivalent horizontal and vertical hydraulic conductivities Formation Thickness (m) Hydraulic Conductivity ( m/day) 1 24 2 8. 12 3 15 4 9 5 6 10 10 8 20 1 10 10 18 11 8. 29 12 29 13 6. 14 3. 16 15 10 26 16 4 9. 17 4. 18 4. 1 19 29 20 25 21 8 12 22 4 23 23 18 24 7. 30 25 8 29 26 6. 28 27 28 28 9. 14 29 4 14 30 2 31 8. 4 32 1 33 3. 19 34 2 13
1. A confined aquifer is recharged by a continuous supply of water from the certain source. The average thickness of the aquifer was determined to be 18 m and the average width is 8 km. The hydraulic conductivity of the aquifer was obtained at 60 m/day and its void ratio is 0.1586. The piezometer heads in two wells 2,145m apart are 128 meters and 188 meters from a common reference datum. Determine: •compute the rate of flow through the aquifer in m3/day •compute the seepage velocity in m/day •compute the time of travel from the head of the aquifer to a point 8 km downstream in days
A confined aquifer shown has hydraulic conductivity of 52 m/day with void ratio of 0.282. The average thickness is 30 m and the average width is 4 km. el = 85 m el = 55 m 30 m aquifer 1400 m Determine the nearest value of the time of travel from the head of aquifer to a point 5.2 km downstream in days (in a whole day).
5. Aquifer shown in figure represents: (a) confined aquifer (b) unconfined aquifer (c) Can be confined and unconfined aquifer 6. Aquifer is defined as: Static water level Equilibrium water level a) It is an underground saturated material which stores ground water. b) It is an underground unsaturated material which stores ground water. 7. The ratio between volume of water yielded by gravity to the volume of unconfined aquifer, is known as: a) Specific mass b) Specific density c) Specific yield 8. Hydraulic radius (R) is: a) Ratio between flow area (A) and wetted perimeter (P) b) Ratio between wetted perimeter (P) and flow area (A)
A confined aquifer is recharged by a continuous supply of water from the certain source. The average thickness of the aquifer was determined to be 25 m and the average width is 4 km. The hydraulic conductivity of the aquifer was obtained at 40 m/day and its void ratio is 0.3333. The piezometer heads in two wells 1.325 km apart are 65 meters and 60 meters from a common reference datum. Determine the rate of flow in cubic meters per day.
Given that: • Hydraulic gradient = 0.43 • unit weight of the saturated soil layer = 19.80Kn/m³ • rate and direction of seepage = 4.29 x 10^-4 m³/s (upward) • moisture content of the fully saturated soil layer = 24.25% Answer the ff: a) What would be the critical value of h to cause boiling b) If the value of h= 1.5 m boiling will? and If the value of h= 4.0 m boiling will? c) The total stress at point B d) The effective stress at point B e) The neutral stress at point B
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