Braja Das Principles of Geotechnical Engineering Chapter 7 Problems 195Direction of flowD Impervious layerFigure 7.297.9 Refer to Figure 7.29. Find the flow rate in m/sec/m length (at right angles tothe cross section shown) through the permeable soil layer. Given: H = 5 m,H = 2.8 m, h = 3.1 m, L = 60 m, a = 5°, k = 0.05 cm/sec.7.10 The hydraulic conductivity of a sand at a void ratio of 0.5 is 0.022 cm/sec.Estimate its hydraulic conductivity at a void ratio of 0.7. Use Eq. (7.31).7.11 For a sand, the following are given: porosity, n = 0.31 and k = 0.2 ft/min.Determine k when n = 0.4. Use Eq. (7.31).7.12 The maximum dry density determined in the laboratory for a quartz sandis 1800 kg/m³. In the field, if the relative compaction is 80%, determine thehydraulic conductivity of the sand in the field-compaction condition (given thatD10 = 0.15 mm, C, = 2.2 and G, = 2.66). Use Eq. (7.34).7.13 For a sandy soil, the following are given:• Maximum void ratio = 0.7• Minimum void ratio = 0.46D10 = 0.2 mmDetermine the hydraulic conductivity of the sand at a relative density of 60%.Use Eq. (7.32).7.14 The sieve analysis for a sand is given in the following table. Estimate thehydraulic conductivity of the sand at a void ratio of 0.5. Use Eq. (7.30) andSF = 6.5.TTU.S. Sieve No.Percent passing3010040606810028200 196 Chapter 7: Permeability7.15 For a normally consolidated clay, the following are given:Void ratio, ek (cm /sec)0.81.2 x 10-61.43.6 x 10-6Estimate the hydraulic conductivity of the clay at a void ratio, e = 0.9. Use Eq. (7.38).7.16 The in situ void ratio of a soft clay deposit is 2.1 and the hydraulic conductivity ofthe clay at this void ratio is 0.91 × 10-6 cm/sec. What is the hydraulic conductivityif the soil is compressed to have a void ratio of 1.1. Use Eq. (7.36).7.17 A layered soil is shown in Figure 7.30. Given that• H = 1.5 m• H = 2.5 mk = 10-5 cm/sec• k2 = 3.0 x 10-³ cm/seckz =3.5 x 10-5 cm/secEstimate the ratio of equivalent hydraulic conductivity, kĦeg/kv{cq}•7.18 A layered soil is shown in Figure 7.31. Estimate the ratio of equivalent hydraulicH3 = 3.0 mconductivity, kµeq/kvieg)•1.5 m1.5 mH2H3k = 2 x 10-3 cm/sec (top layer)| k = 2 × 10-4 cm/seck = 10-4 cm/seck = 3 x 10-4 cm/sec (bottom layer)Figure 7.30Figure 7.31

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Refer to Figure 7.29. Find the flow rate in m'/sec/m length (at right angles to the cross section shown) through the permeable soil layer. Given: H = 5 m, H, = 2.8 m, h = 3.1 m, L = 60 m, a = 5°, k = 0.05 cm/sec.

Refer to Figure 7.29. Find the flow rate in m'/sec/m length (at right angles to the cross section shown) through the permeable soil layer. Given: H = 5 m, H, = 2.8 m, h = 3.1 m, L = 60 m, a = 5°, k = 0.05 cm/sec.

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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