2000 Two soil specimens with identical geometric dimensions were subjected to falling head permeability tests in the laboratory under identical conditions. The fall of water head was measured after an identical time interval. The ratio of initial to final water heads for the test involving the first specimen was 1.25. If the coefficient of permeability of the second specimen in 5 times that of the first, the ratio of initial to final water heads in the test involving the second specimen is

2000 Two soil specimens with identical geometric dimensions were subjected to falling head permeability tests in the laboratory under identical conditions. The fall of water head was measured after an identical time interval. The ratio of initial to final water heads for the test involving the first specimen was 1.25. If the coefficient of permeability of the second specimen in 5 times that of the first, the ratio of initial to final water heads in the test involving the second specimen is

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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Afalling-head permeability test is performed on a fine-grained soil. The soil sample has a length of 120 mm and a cross-sectional area of 600 mm2. The water in the standpipe flowing into the soil is 0.60 m above the top of the sample at the start of the test. It falls 50 mm in 30 minutes. The standpipe has a cross-sectional area of 200 mm2. (a) Make a sketch of the described conditions. (b) What is the coefficient of permeability in millimeters per second? (c) What is the coefficient of permeability in feet per minute? (d) On the basis of the calculated value for khyd, what is the probable soil type?
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Don't attempt wrong i will downvote.....A cylindrical soil sample, 7.3 cm in diameter and 16.8 cm in height, is tested in a constant-head permeability apparatus. A constant head of 75 cm is maintained during the test. After 1 minute of testing, a total of 945.7 gm of water was collected. The temperature was 20 oC. The void ratio of the soil was 0.43. Calculate the following: 1. The hydraulic gradient 2. The flow rate 3. The discharge velocity 4. The seepage force per unit volume 5. The coefficient of permeability
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The following results of a falling head permeability test. Calculate the permeabilityof the soil sample Diameter of sample: 100 mmDiameter of feeder pipe: 20 mmLength of sample: 500 mmFlow through the sample: 1.3 l/sDistance between tappings: 450 mmHead loss: 1650 mm