Impervious lay Figure 7.31 A The results of a constant-head permeability test for a fine sand sample diameter of 70 mm and a length of 140 mm are as follows (refer to Fi .Constant-head difference 550 mm . Water collected in 7 min = 450 cm3 . Void ratio of sand = 0.8 %3D Determine: a. Hydraulic conductivity, k (cm/sec) b. Seepage velocity 77 In a constant-head permeability test, the length of the specimen and the cross sectional area is 78.5 cm2. If k = 2.1 X 10-2 cm/sec, ar flow of 130 cm/min has to be maintained during the test, what shG head difference across the specimen? 7.8 The following data are for a falling-head permeability test: • Length of the soil sample • Diameter of soil sample = • Area of the standpipe = 19.6 mm2 • At time t = 0, head difference = 500 mm • At time t =7 min, head difference = 350 mm a. Determine the hydraulic conductivity of the soil (cm/sec) b. What was the head difference at t =5 min? 7.9 The following data are for a falling-head permeability test: Length of the soil sample = 400 mm • Area of the soil sample = 7854 mm2 • Diameter of the standpipe = 11 mm %3D =140mm 70mm %3D %3D %3D %3D %3D %3D %3D %3D

Impervious lay Figure 7.31 A The results of a constant-head permeability test for a fine sand sample diameter of 70 mm and a length of 140 mm are as follows (refer to Fi .Constant-head difference 550 mm . Water collected in 7 min = 450 cm3 . Void ratio of sand = 0.8 %3D Determine: a. Hydraulic conductivity, k (cm/sec) b. Seepage velocity 77 In a constant-head permeability test, the length of the specimen and the cross sectional area is 78.5 cm2. If k = 2.1 X 10-2 cm/sec, ar flow of 130 cm/min has to be maintained during the test, what shG head difference across the specimen? 7.8 The following data are for a falling-head permeability test: • Length of the soil sample • Diameter of soil sample = • Area of the standpipe = 19.6 mm2 • At time t = 0, head difference = 500 mm • At time t =7 min, head difference = 350 mm a. Determine the hydraulic conductivity of the soil (cm/sec) b. What was the head difference at t =5 min? 7.9 The following data are for a falling-head permeability test: Length of the soil sample = 400 mm • Area of the soil sample = 7854 mm2 • Diameter of the standpipe = 11 mm %3D =140mm 70mm %3D %3D %3D %3D %3D %3D %3D %3D

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 6.7P

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