Civil Engineering Reference
In-Depth Information
Exercise 1.7
A sample of moist sand was cut out of a natural deposit by means of a sampling
cylinder. The volume of the cylinder was 478 ml; the weight of the sample alone was
884 g and 830 g after drying. The volume of the dried sample, when rammed tight
into a graduated cylinder, was 418 ml and its volume, when poured loosely into the
same cylinder, was 616 ml. If the particle specific gravity was 2.67, compute the
density index and the degree of saturation of the deposit.
Answer
I
D
=
69%, S
r
=
32%
Exercise 1.8
In order to determine the density of a clay soil an undisturbed sample was taken in
a sampling tube of volume 0.001 664 m
3
.
The following data were obtained:
Mass of tube (empty)
=
1.864 kg
Mass of tube and clay sample
=
5.018 kg
Mass of tube and clay sample after drying
=
4.323 kg
Calculate the water content, the bulk, and the dry densities. If the particle specific
gravity was 2.69, determine the void ratio and the percentage saturation of the clay.
Answer
w
=
28%,
ρ
d
=
1.49 Mg/m
3
,
ρ
b
=
1.90 Mg/m
3
, S
r
=
93%, e
=
0.82
