Civil Engineering Reference
In-Depth Information
shown. Figure 2.12(b) shows the corresponding displacement diagram. Scaling from
the diagram, or by calculation,
δ
h
=
2 mm.
Example 2.3: Stress analysis using a Mohr circle of stress
Figure 2.13(a) shows an ele-
ment of soil behind a retaining wall; the effective vertical and horizontal stresses are
σ
100 kPa and these are principal stresses. Figure 2.13(b) shows
the Mohr circle of stress. Scaling from the diagram,
=
300 kPa and
σ
h
=
z
30
◦
, the angles of the crit-
φ
m
=
60
◦
and the stresses on these planes are
ical planes are
α
=
β
=
σ
=
150 kPa and
τ
=±
87 kPa.
Figure 2.13
Example 2.4: Analysis of strain using a Mohr circle of strain
Figure 2.14(a) illustrates
an increment of displacement of a retaining wall from the broken to the solid lines.
The strains in an element of soil behind the wall are
0.20%
and these are principal strains. Figure 2.14(b) shows the Mohr circle for the incre-
ment of strain. Scaling from the diagram, the angle of dilation is
δε
=
0.10% and
δε
h
=−
z
20
◦
. The zero
ψ
=
Figure 2.14
