Principles of Geotechnical Engineering (MindTap Course List)
9th Edition
ISBN: 9781305970939
Author: Braja M. Das, Khaled Sobhan
Publisher: Cengage Learning
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Chapter 7, Problem 7.22P
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
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Question 2
* A well with a diameter of 0.6 m is constructed in a confined aquifer. The sand aquifer has a uniform
thickness of 15 m, overlain by an impermeable layer with a depth of 35 m. A pumping test was conducted
to determine the coefficient of permeability of the aquifer. The initial piezometric surface was 15 m. below
the ground surface datum of the test well and observation wells. After water was pumped at a rated of
13 liters/sec for several days, water levels in the wells stabilized with the following drawdowns, 6.4 m in
the test well, 3.7 m in the observation well 10 m from the test well, and 2.4 m in the second observation
well at a distance of 30 m. From these data:
o Find the depth of the water in the test well
Calculate the permeability of the aquífer.
The results of a constant-head permeability test for a
sand sample having a sectional area of 10000mm2
and a length of 200 mm are as follows: (1) Constant
head difference 400mm (2) Time of collection of water
= 30 seconds (3) Volume of water collected = 600
cm3. The hydraulic conductivity is:
Oa. 1.0 mm/sec
Ob. 1,7mm/sec
c. 2.9 mm/sec
O d. 0.5mm/sec
Find out the change in length in a rock mass. while the strain recorded is 3% and the original length of that mass is 4 cm. Q:5 b) How the property of permeability generates in soil and find out the hydraulic conductivity of a rock when change in height is 6 cm and the original height of the sample is 8 cm. the volume recorded in outlet is 20cm^3 in 20 min. the diameter of intact saturated rock mass is 5 cm. *
Chapter 7 Solutions
Principles of Geotechnical Engineering (MindTap Course List)
Ch. 7 - Prob. 7.1PCh. 7 - Prob. 7.2PCh. 7 - Prob. 7.3PCh. 7 - Prob. 7.4PCh. 7 - Prob. 7.5PCh. 7 - Prob. 7.6PCh. 7 - Prob. 7.7PCh. 7 - Prob. 7.8PCh. 7 - Prob. 7.9PCh. 7 - Prob. 7.10P
Ch. 7 - Prob. 7.11PCh. 7 - Prob. 7.12PCh. 7 - Prob. 7.13PCh. 7 - Prob. 7.14PCh. 7 - Prob. 7.15PCh. 7 - Prob. 7.16PCh. 7 - Prob. 7.17PCh. 7 - Prob. 7.18PCh. 7 - Prob. 7.19PCh. 7 - Prob. 7.20PCh. 7 - Prob. 7.21PCh. 7 - Refer to Figure 7.24. The following data were...Ch. 7 - Prob. 7.23PCh. 7 - Prob. 7.1CTP
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