Chapter 7 | Permeability Problems 7.1 Apermeable soil layer is underlain by an impervious layer as shown in Figure 7.29 Knowing that k = 6 × 10-3 cm/sec for the permeable layer, calculate the rate of seepage through this layer in m/hr/m width. Given: H = 5.4 m and a = 7°. Groundwater table (free surface) Н Direction of seepage Impervious layer Ground surface Figure 7.29 7.2 Redo Problem 7.1 for a = 5° and a = 9°. All other site conditions remaining the same, what impact does the slope angle have on the rate of seepage! 7.3 Seepage is occurring through the sandy layer underneath the concrete dam shown in Figure 7.30. H1 Concrete dam

Chapter 7 | Permeability Problems 7.1 Apermeable soil layer is underlain by an impervious layer as shown in Figure 7.29 Knowing that k = 6 × 10-3 cm/sec for the permeable layer, calculate the rate of seepage through this layer in m/hr/m width. Given: H = 5.4 m and a = 7°. Groundwater table (free surface) Н Direction of seepage Impervious layer Ground surface Figure 7.29 7.2 Redo Problem 7.1 for a = 5° and a = 9°. All other site conditions remaining the same, what impact does the slope angle have on the rate of seepage! 7.3 Seepage is occurring through the sandy layer underneath the concrete dam shown in Figure 7.30. H1 Concrete dam

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 7.2P

See similar textbooks

Similar questions

Refer to Figure 7.24. The following data were collected during the field permeability measurement of a confined aquifer using a pumping test. Determine the hydraulic conductivity of the permeable layer. Use Eq. (7.49). Thickness of the aquifer, H = 4.5 m Piezometric level and radial distance of the first observation well: h1 = 2.9 m; r1 = 17.8 m Piezometric level and radial distance of the second observation well: h2 = 1.8 m; r2 = 8.1 m Rate of discharge from pumping, q = 0.5 m3/min
A concrete dam retains water to a height of 9 m. It has rows of sheet piling at both heeland toe which extend half way down to an impervious stratum. From a flow net sketchedon a transformed section, it is found that there are four flow channels and sixteen headdrops. The average horizontal and vertical permeabilities of the soil are 6 × 10^–3 mm/sand 2 × 10^–3 mm/s, respectively. What is the seepage in cubic meter per day, if the lengthof the dam is 150 meters?
A permeable soil layer is underlain by an impervious layer as shown below. Knowing that k = 6 x 10 -3 cm/sec for the permeable layer. Given H = 5.4 m, calculate the rate of seepage through this layer in m 3 /hr. if: α = 5 o α = 7 o α = 9 o α = 12 o Draw a chart α vs. q (i.e. α on the x-axis, and q on the y-axis) and discuss how the slope angle (α) impact the flow rate and explain the reason for such behavior.
Determine the following: 1. How high water will rise in piezometers at points a, b, c, d. 2. Total rate of seepage
Given: velocity of flow = 0.0375 m/s coefficient =0.05 m/s porosity p =48% slope S = 3/4 The soil porosity in the area where the 46-cm diameter well is 48%, find the discharge of the groundwater. Given the coefficient =0.05 m/s and porosity p =48%, find the transmissibility (T) in m/s per unit m, if the aquifer width is 1.2 m. Given the discharge Q get in Question #1, transmissibility T in Question#2, slope S = 3/4; find the aquifer width X.
A layer of silty soil of thickness 5 m lies below the ground surface at a particular site and below the silt layer lies a clay stratum. The ground water table is at a depth of 4 m below the ground surface.The following data are available for both the silt and clay layers of soil.Silt layer: ?10 = 0.018 mm, e = 0.7, and Gs = 2.7Clay layer: e = 0.8 and Gs = 2.75Required: (a) Height of capillary rise, (b) capillary pressure, (c) the effective pressure at the ground surface, at groundwater table (GWT) level, at the bottom of the silt layer and at a depth of H =6 m below ground level, and (d) at a depth 2 m below ground level. (Sketch or draw the stress distribution diagram).
The section size of a water pipe is (100cm Χ 100cm), three types of soils A, B, and C are placed in the pipe, and a fixed amount of water is injected into the top left tap to keep the water head difference between the left and right ends of the pipe 60cm. The three soil permeability coefficients are k_A = 0.05 cm/sec , K_B = 0.1 cm/sec, k_C = 0.001 cm/sec, please calculate the following values:(1) The fixed amount of water injected into the faucet on the upper left (cm3/hr)(2) What is the total water head consumed by each of the three soils of A, B, and C (cm)(3) The overall volumetric seepage force of water flowing through the three soils (kN/m3)
The SQUARE base permeameter (seen from above), has three soil layers arranged vertically as shown in the image. L is: 70cm, the difference of head h is: 105 cm. The coefficient of permeability of soil 1 K1 is 0.065 cm/sec, soil 2 K2 is 0.0030 cm/sec and soil 3 K3 is the 0.0095 Calculate the amount of water collected in a time of 10 minutes.
The section of a concrete gravity dam with its flow net diagram is shown in Pigure 10.38. The coefficient of permeability of the soil (anistropic) in the vertical and horizontal directions are 0.25 m/day and 0.58 m/day, respectively. The length of dam perpendicular to the paper is 120 m. 1. Determine the number of pressure drops 2. Determine the seepage loss 3. Determine the total amount of water percolated in one year.
A layer of silty soil of thickness 5 m lies below the ground surface at a particular site and below thesilt layer lies a clay stratum. The ground water table is at a depth of 4 m below the ground surface.The following data are available for both the silt and clay layers of soil. Silt layer: ?10= 0.018 mm, e= 0.7, and Gs = 2.7Clay layer: e = 0.8 and Gs = 2.75Required: (a) Height of capillary rise, (b) capillarypressure, (c) the effective pressure at theground surface, at groundwater table (GWT)level, at the bottom of the silt layerand at a depth of H =6 m below groundlevel, (d) at a depth 2 m below ground level.(Sketch or draw the stress distribution diagram).
Find the seepage velocity through soil 1 if the average velocity is 0.0073 meters per second. Use 3 decimal places. H1 = 1.25 m n1 = 32%H2 = 2.51 m n2 = 22% H3 = 2.51 m n3 = 28%
A drainage pipe became completely blocked during/ a storm by a plug of sand, 1.5 m long, followed by another plug of a mixture of clays, silts and sands, 0.5m long, as shown in the attached figure. When the storm was over, the water level above ground was 1 m. The coefficient of permeability of the sand is 2x that of the mixture of clays, silts and sands. a. Calculate the pore water pressure at the center of the sand plug in kPa.Calculate the pore water pressure at the center of the mixture of clays, silts and sands in kPa. Find the average hydraulic conductivity in the sand. Find the average hydraulic conductivity in the mixture of clays, silts and sands