CE161P-2/A21 12-04-21
1 Problem:
During a constant head permeability test on a sample of sand, 150 cu.cm. of water were
collected in 2 minutes. The sample had a length of 10 cm. and a diameter of 5.08 cm. The
head was maintained at 20 cm.
a) Compute the coefficient of permeability
b) What type of soil is this?
c) Compute the seepage velocity if the porosity of soil 0.30.
2 Problem:
From the constant head permeability test arrangement shown, the following values are
given:
Void ratio of specimen ........ 0.46
Length of soil sample ........... 450 mm
Constant head difference .......700 mm
, Water collected in a period of 3 min
= 0.000354 m3
Cross sectional area of soil sample
= 0.00226 m2
a) Determine the coefficient of permeability.
b) Compute the discharge velocity in m/min.
c) Compute the seepage velocity in m/min.
3 Problem:
The MMDA in its previous study for a proposed sanitary land fill site in Cavite is
planning to use a clay liner for the landfill. Tests were performed on a sample clay from
a borrow site. It was deemed necessary to have a minimum clay liner thickness of 0.30
m. The following results were obtained in the laboratory test.
Initial water level in standpipe … 96 cm. Final water level in standpipe ….
56 cm. Diameter of standpipe ... 12 mm.
Height of soil sample ................. 10.2 cm.
Diameter of soil sample .............. 5.4 cm.
Duration of test .......................... 12 hours.
The project manager would like to determine the effectiveness of using
on-site day soils for the lining material if it is a favorable. Tests were
also performed on the on-site clay and the following results were
obtained.
Height of soil sample ............... 8 cm.
Diameter of soil sample ...........5 cm.
Volume of water collected .......75600 cm3
Constant head .......................... 60 cm.