Geoscience Reference
In-Depth Information
Table 21.5
(
Continued
)
Friction angle
Bearing capacity factors
Vesic
Hansen
φ
N
N
γ
γ
N
c
N
q
10 (Clay undrained condition)
8.3
2.47
1.22
0.39
11
8.8
2.71
1.44
0.50
12
9.3
2.97
1.69
0.63
13
9.8
3.26
1.97
0.78
14
10.4
3.59
2.29
0.97
15 (Clay undrained condition)
11.0
3.94
2.65
1.18
16
11.6
4.34
3.06
1.43
17
12.3
4.77
3.53
1.73
18
13.1
5.3
4.07
2.08
19
13.9
5.8
4.68
2.48
20 (Soft clays effective strength)
14.8
6.4
5.4
2.95
21
15.8
7.1
6.2
3.50
22
16.9
7.8
7.1
4.13
23
18.0
8.7
8.2
4.88
24
19.3
9.6
9.4
5.75
25 (Very stiff clays)
20.7
10.7
10.9
6.76
26
22.2
11.9
12.5
7.94
27
23.9
13.2
14.5
9.32
28
25.8
14.7
16.7
10.9
29
27.9
16.4
19.3
12.8
30 (Loose sand)
30.1
18.4
22.4
15.1
31
32.7
20.6
26.0
17.7
32
35.5
23.2
30.2
20.8
33
38.6
26.1
35.2
24.4
34
42.2
29.4
41.1
28.8
35 (Medium dense sand)
46.1
33.3
48.0
33.9
36
51
37.8
56
40.0
37
56
42.9
66
47.4
38
61
48.9
78
56
39
68
56
92
67
40 (Dense sand)
75
64
109
80
41
84
74
130
95
42
94
85
155
114
43
105
99
186
137
44
118
115
225
166
45 (Very dense gravel)
134
135
272
201
21.6 Bearing capacity of cohesive soils
•
0
◦
and N
c
For a fully undrained condition in cohesive soils
φ
=
=
5.14.
•
For a surface footing the Ultimate Bearing Capacity (q
ult
)
=
N
c
C
u
(strip footing).
•
The bearing capacity increases with the depth of embedment. The change of N
c
with the depth of embedment and the type of footing is provided in the table below.
•
Often this simple calculation governs the bearing capacity as the undrained
condition governs for a clay.
Search WWH ::
Custom Search