13. The soil profile below a lake with water level at elevation = 0 m and lake bottom at elevation = -10 m is shown in the figure, where k is the permeability coefficient. A piezometer (stand pipe) installed in the sand layer shows a reading of +10 m elevation. Assume that the piezometric head is uniform in the sand layer. The quantity of water (in m³/s) flowing into the lake from the sand layer through the silt layer per unit area of the lake bed is: %3D %3D Stand pipe +10 Lake Lake bottom 宣-10 Silt (k = 10-6 m/s) -30 Sand (under artesian pressure) -40 Rock (A) 1.5 x 10-6 (C) 1.0 x 10-6 (B) 2.0 x 10-6 (D) 0.5 x 10-6 Elevation (m)

13. The soil profile below a lake with water level at elevation = 0 m and lake bottom at elevation = -10 m is shown in the figure, where k is the permeability coefficient. A piezometer (stand pipe) installed in the sand layer shows a reading of +10 m elevation. Assume that the piezometric head is uniform in the sand layer. The quantity of water (in m³/s) flowing into the lake from the sand layer through the silt layer per unit area of the lake bed is: %3D %3D Stand pipe +10 Lake Lake bottom 宣-10 Silt (k = 10-6 m/s) -30 Sand (under artesian pressure) -40 Rock (A) 1.5 x 10-6 (C) 1.0 x 10-6 (B) 2.0 x 10-6 (D) 0.5 x 10-6 Elevation (m)

Fundamentals of Geotechnical Engineering (MindTap Course List)

5th Edition

ISBN:9781305635180

Author:Braja M. Das, Nagaratnam Sivakugan

Publisher:Braja M. Das, Nagaratnam Sivakugan

Chapter6: Hydraulic Conductivity

Section: Chapter Questions

Problem 6.16P

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Seepage around a retaining wall is shown in the figure below. The hydraulic conductivity of the sand is 1.8 x 10-5 cm/s. The retaining wall is 20 m long. Determine the quantity of seepage across the entire wall per day
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