Falling Head Permeability Test $-$ Fine Sand

$*$Water height in burette measured from datum at top of table $($base of apparatus$).$

Water temperature during test $=24\mathrm{.}0$ degrees C

Standpipe Diameter, $d=1\mathrm{.}5cm$ Using relevant data from Question $1,$ estimate the saturated $k(c\frac{m}{s})$ using the Kozney$-$Carman

equation assuming spherical particles of $D_{10}$ size. See the note below for estimating void ratio.

Note: $2.$ This information will help you compute void ratio, e$.$

In each device, the volume of soil being tested is contained

inside a plexiglas cylinder of interior length $L$ and diameter $D.$

The soil is placed dry and the Lab Test Specimen Setup table

above provides the mass of dry soil $($Ms$)$ that makes up the

sample. Refer to the Permeability Notes for a sketch of each

test device. The diameter, D$,$ of all laboratory test specimens $=$

$6\mathrm{.}2$ cm $.$

$G_s=2\mathrm{.}65$The coefficient of permeability of sands can be directly measured in the laboratory by using

either the Constant Head permeability test or the Falling Head permeability test. Refer to the

Direct Methods discussion in the Permeability Notes handout located on Canvas.

Data from a constant head test conducted a specimen of coarse sand at one head difference

are included in the table below. Data are also included for a falling head test conducted on a

fine sand specimen.

$($a$)$ Please use the data to estimate the saturated permeability coefficient in units of $c\frac{m}{sec}$ of

the two soils $($coarse sand, fine sand$).$

$($b$)$ How do your permeability values in b$)$ and c$)$ above compare to values given in the table of

typical permeability ranges we discussed in class?

Permeability Test Data

The soil was placed in the permeability devices when dry, then the soil was saturated with water

before the test started. See the sketch of the specimen on the next page.

Diameter of all laboratory test specimens $=6\mathrm{.}2cm.,G_s=2\mathrm{.}65.$

Laboratory Data

Constant Head Permeability Test $-$ Coarse Sand

Water temperature during test $($deg$.$ C$)$: $26\mathrm{.}5$