Geoscience Reference
In-Depth Information
•
For layered systems and/or non uniform loading, the above stress distribution does
not apply. Poulos and Davis (1974) is the standard reference for these alternative
solutions.
Table 24.5
Vertical stress changes (originally from Janbu, Bjerium and Kjaernsli, 1956, but here from
graphs in Simons and Menzies, 1977).
Depth below base of footing
Footing shape in terms of
Change in stress
p in terms of applied
(z) in terms of width (B)
length (L)
stress q
z/B
0.5
Square (L
B)
p/q
0.70
=
=
=
L
=
2B
p/q
=
0.82
L
5B
p/q
0.82
=
=
L
10B
p/q
0.82
=
=
L
p/q
0.82
=∞
=
z/B
1.0
Square (L
B)
p/q
0.33
=
=
=
L
=
2B
p/q
=
0.49
L
5B
p/q
0.56
=
=
L
=
10B
p/q
=
0.56
L
p/q
0.56
=∞
=
z/B
=
2.0
Square (L
=
B)
p/q
=
0.12
L
2B
p/q
0.20
=
=
L
5B
p/q
0.28
=
=
L
=
10B
p/q
=
0.30
L
p/q
0.30
=∞
=
z/B
=
3.0
Square (L
=
B)
p/q
=
0.06
L
2B
p/q
0.11
=
=
L
=
5B
p/q
=
0.17
L
10B
p/q
0.20
=
=
L
p/q
0.22
=∞
=
z/B
5.0
Square (L
B)
p/q
0.02
=
=
=
L
2B
p/q
0.04
=
=
L
=
5B
p/q
=
0.08
L
10B
p/q
0.11
=
=
L
p/q
0.14
=∞
=
Search WWH ::
Custom Search