Civil Engineering Reference
In-Depth Information
CLAY: c' = 8 kN/m
2
γ
= 18.5 kN/m
3
3.0 m
φ
' = 23°
SAND: c' = 0
5.0 m
γ
= 20 kN/m
3
φ
' = 32°
Fig. 7.32
Exercise 7.3.
Exercise 7.4
A soil has the following properties:
γ
=
18 kN/m
3
,
φ
′
=
30°, c
′
=
5 kPa. The soil is
retained behind a 6 m high vertical wall and has a horizontal surface level with the
top of the wall.
If
′
=
w
5
and
δ
=
15°, determine the total active horizontal thrust acting on
the back of the wall:
c
kPa
(i) with no surcharge acting on the retained soil;
(ii) when the surface of the soil is subjected to a vertical uniformly distributed pres-
sure of 30 kPa.
(Use the values of K
a
and K
ac
from the
earth pressure coefficients
spreadsheet)
Answer
(i) 59.6 kN; (ii) 100.5 kN (K
a
=
0.29 and K
ac
=
1.53)
