Notes:: Project Title: Client Contract No.
Notes:: Project Title: Client Contract No.
Notes:: Project Title: Client Contract No.
Title:
Checked By:
Job No.
Doc No.:
=
=
106
23.5
m
1
Average Net Pressure developed at the bottom of tank
= qo =
250
kN/m
Notes:
1) All yellow highlighted cells are input cells.
2) Introduce layers of soil at the interface of ground water table if any & at the foundation bottom for ease of calculation of effective stress.
3) Introduce layers representing typical average SPT value, if required.
4) Immediate settlement to be cosnidered for Sand layers.
5) Clay layers which are above ground water table and are above sand (drainage layer) immediate settlements to be considered.
However if the water table is within the clay layer OR at bottom of clay layer(i.e. clay layer in contact with water table), consider consolidation
settlements & ignore immediate settlement for the complete layer as it is deemed to be saturated by cappilary action of ground water table.
6) Consoldation settlements shall be considered for clay layers those are below ground water table and under the stress zone of tank/ring
foundation.
7) Minimum Depth of stress influence below tank for settlement calculations shall be equal to "depth where increase in stress due to
tank load is less than 20% of effective over burden pressure" (i.e. p/p'0 <0.2).
1.0) Calculation of Settlement at Tank Center
Total settlement at tank center is calculated as immediate + consolidation settlements as given below
1.1) Calculation of Immediate Settlement at center of tank
Boussinesq Method is used for Calculating Vertical Pressure over a Circular Area
Following formula (Boussinesq Equation) is used to calculate vertical stress beneath the center of an circle of radius
r' and at a depth 'z' is [ Ref. Eq. 5-6 of "Foundation Analysis And Design"
(fifth edition) by Joseph E. Bowel ]
The immediate settlement is calculated with the following formula
Hi = (qv * H) / E
Where
Hi = Immediate settlement of layer, mm
E = Elastic modulus of soil layer, MPa
H = Thickness of layer, m
Reference Borehole Number =
BH 01 (FV)
1.000
4.500
4.500
6.000
m
7.5
(Enter high value for no water table )
Fdn.
qv At
Immediate
Bott. to
Average
Layer Thkness
centre of
Elastic Modulus
Settlement
layer
Field SPTwrt fdn bottom,
layer
of soil E, MPa
considered?
cen.
N
value
m
YES/NO*
(kN/m2)
z (m)
0.0
13
14
NO
0.0
Thick. Of
layer hi
(m)
FGL to
layer
centre
(m)
1.000
0.500
Sand
3.500
2.750
1.750
250.0
23
23
Sand
1.500
5.250
4.250
249.9
23
23
_____________________________________________
249016848.xlsx.ms_office
0.0
3.5
3.5
5.0
___________________________________________
Settlement-center
Immediate
Settlement
for each
layer Hi ,
mm
0.00
YES
38.04
YES
16.30
___________________________________________
Sheet 1 of 8
Project Title:
Title:
Checked By:
Job No.
04
05
6.000
7.500
7.500
9.000
Doc No.:
Sand
1.500
6.750
5.750
249.7
73
80
Sand
1.500
8.250
7.250
249.4
50
75
_____________________________________________
249016848.xlsx.ms_office
5.0
6.5
6.5
8.0
___________________________________________
Settlement-center
YES
4.68
YES
4.99
___________________________________________
Sheet 2 of 8
Project Title:
Title:
Checked By:
Job No.
06
07
08
09
10
11
12
13
14
15
16
17
18
19
20
21
22
9.000
10.500
10.500
12.000
12.000
15.000
15.000
18.000
18.000
24.000
24.000
25.500
25.500
27.000
27.000
30.000
30.000
32.000
32.000
36.000
36.000
39.000
39.000
45.000
45.000
50.000
50.000
55.000
55.000
60.000
60.000
65.000
65.000
70.000
Doc No.:
Sand
1.500
9.750
8.750
248.9
34
34
Clay
1.500
11.250
10.250
248.3
22
22
Clay
3.000
13.500
12.500
247.0
27
27
Clay
3.000
16.500
15.500
244.5
39
60
Clay
6.000
21.000
20.000
239.0
48
60
Sand
1.500
24.750
23.750
232.9
48
75
Sand
1.500
26.250
25.250
230.1
70
80
Sand
3.000
28.500
27.500
225.6
60
80
Sand
2.000
31.000
30.000
220.1
69
80
Sand
4.000
34.000
33.000
213.1
55
80
Sand
3.000
37.500
36.500
204.4
63
80
Sand
6.000
42.000
41.000
192.7
58
80
Sand
5.000
47.500
46.500
178.3
65
80
Sand
5.000
52.500
51.500
165.4
70
80
Sand
5.000
57.500
56.500
153.0
75
80
Sand
5.000
62.500
61.500
141.3
80
80
Sand
5.000
67.500
66.500
130.4
80
80
8.0
9.5
9.5
11.0
11.0
14.0
14.0
17.0
17.0
23.0
23.0
24.5
24.5
26.0
26.0
29.0
29.0
31.0
31.0
35.0
35.0
38.0
38.0
44.0
44.0
49.0
49.0
54.0
54.0
59.0
59.0
64.0
64.0
69.0
YES
10.98
NO
0.00
NO
0.00
NO
0.00
NO
0.00
YES
4.66
YES
4.31
YES
8.46
YES
5.50
YES
10.65
YES
7.66
YES
14.45
YES
11.14
YES
10.34
YES
9.56
YES
8.83
YES
8.15
178.73
mm
* Enter YES to include immediate settlement & NO to exclude. If clay layer excluded in immediate settlement, it should be included in
consolidation settlement.
1.2) Settlement due to consolidation at Tank Center
The consolidation settlement is calculated with the help of the following formula in
H = mv (P) H
Where
H = Consolidation settlement of layer, mm
mv = Modulus of volume compressibility, m2/kN
P = Increase in pressure at centre of layer , kN/m2
H = Thickness of layer, m
Soil Data
Layer Type of
Sr. Depth
Soil
No. bel. FGL (Sand /
z (m)
Clay)
01
0.000
Thick. Of
layer hi
(m)
FGL to Density
Average
layer of soil **
Plasticity
Field SPTg
bottom
Index (%)
i
N value
(m)
(kN/m3)
Sand
1.000
1.000
20.0
_____________________________________________
249016848.xlsx.ms_office
13
f2 (Fig 5.15 of
Tomlinson)
Modulus of
Volume
Compressibility,
m2/MN
0
0.00
0.00
___________________________________________
Settlement-center
___________________________________________
Sheet 3 of 8
Project Title:
Title:
Checked By:
Job No.
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
19
20
21
22
1.000
1.000
4.500
4.500
6.000
6.000
7.500
7.500
9.000
9.000
10.500
10.500
12.000
12.000
15.000
15.000
18.000
18.000
24.000
24.000
25.500
25.500
27.000
27.000
30.000
30.000
32.000
32.000
36.000
36.000
39.000
39.000
45.000
45.000
50.000
50.000
55.000
55.000
60.000
60.000
65.000
65.000
70.000
Doc No.:
13
0.00
0.00
19.0
23
0.00
0.00
6.000
19.0
23
0.00
0.00
1.500
7.500
19.0
73
0.00
0.00
Sand
1.500
9.000
9.0
50
0.00
0.00
Sand
1.500
10.500
9.0
34
0.00
0.00
Clay
1.500
12.000
9.0
22
21
0.55
0.08
Clay
3.000
15.000
9.0
27
21
0.55
0.07
Clay
3.000
18.000
9.0
39
23
0.50
0.05
Clay
6.000
24.000
9.0
48
23
0.50
0.04
Sand
1.500
25.500
9.0
48
0.00
0.00
Sand
1.500
27.000
9.0
70
0.00
0.00
Sand
3.000
30.000
9.0
60
0.00
0.00
Sand
2.000
32.000
9.0
69
0.00
0.00
Sand
4.000
36.000
9.0
55
0.00
0.00
Sand
3.000
39.000
9.0
63
0.00
0.00
Sand
6.000
45.000
9.0
58
0.00
0.00
Sand
5.000
50.000
9.0
65
0.00
0.00
Sand
5.000
55.000
9.0
70
0.00
0.00
Sand
5.000
60.000
9.0
75
0.00
0.00
Sand
5.000
65.000
9.0
80
0.00
0.00
Sand
5.000
70.000
9.0
80
0.00
0.00
Sand
1.000
1.000
20.0
Sand
3.500
4.500
Sand
1.500
Sand
** Enter bulk density for soil layers above ground water table & submerged density for soil layers below ground water table.
Calculation of Consolidation Settlement
Layer
Ovbur.
Layer Type of
Consolidatio Consolidation
Eff. Ov.
Thick. Of
thick
PrePress.
Dp/p'0
Incr. in Press. Dp
Sr. Depth
Soil
n settlement Settlement for
Press. p'0
layer hi wrt fdn.
OCR
consolidation
P'0
No. bel. FGL (Sand /
considered? each layer H,
(kN/m2)
2
bott.
Pr, kPa
(m)
(kN/m
)
2
z (m)
Clay)
YES/NO*
mm
(kN/m )
z (m))
0.000
0.000
0.0
01
Sand
1.000
NO
_____________________________________________
___________________________________________
___________________________________________
249016848.xlsx.ms_office
Settlement-center
Sheet 4 of 8
Project Title:
Title:
Checked By:
Job No.
01
02
03
04
05
1.000
1.000
4.500
4.500
6.000
6.000
7.500
7.500
9.000
Sand
1.000
Sand
3.500
Sand
1.500
Sand
1.500
Sand
1.500
Doc No.:
0.000
NO
0.0
0.000
0.0
3.500
66.5
3.500
66.5
5.000
95.0
5.000
95.0
6.500
123.5
6.500
123.5
8.000
137.0
_____________________________________________
249016848.xlsx.ms_office
33.3
1.0
33.3
250.0
7.52
NO
80.8
1.0
80.8
249.9
3.09
NO
109.3
1.0
109.3
249.7
2.29
NO
130.3
1.0
130.3
249.4
1.91
NO
___________________________________________
Settlement-center
___________________________________________
Sheet 5 of 8
Project Title:
Title:
Checked By:
Job No.
06
07
08
09
10
11
12
13
14
15
16
17
18
19
20
21
22
9.000
10.500
10.500
12.000
12.000
15.000
15.000
18.000
18.000
24.000
24.000
25.500
25.500
27.000
27.000
30.000
30.000
32.000
32.000
36.000
36.000
39.000
39.000
45.000
45.000
50.000
50.000
55.000
55.000
60.000
60.000
65.000
65.000
70.000
Doc No.:
Sand
1.500
Clay
1.500
Clay
3.000
Clay
3.000
Clay
6.000
Sand
1.500
Sand
1.500
Sand
3.000
Sand
2.000
Sand
4.000
Sand
3.000
Sand
6.000
Sand
5.000
Sand
5.000
Sand
5.000
Sand
5.000
Sand
5.000
8.000
137.0
9.500
150.5
9.500
150.5
11.000
164.0
11.000
164.0
14.000
191.0
14.000
191.0
17.000
218.0
17.000
218.0
23.000
272.0
23.000
272.0
24.500
285.5
24.500
285.5
26.000
299.0
26.000
299.0
29.000
326.0
29.000
326.0
31.000
344.0
31.000
344.0
35.000
380.0
35.000
380.0
38.000
407.0
38.000
407.0
44.000
461.0
44.000
461.0
49.000
506.0
49.000
506.0
54.000
551.0
54.000
551.0
59.000
596.0
59.000
596.0
64.000
641.0
64.000
641.0
69.000
686.0
143.8
1.0
143.8
248.9
1.73
NO
157.3
1.4
220.2
248.3
1.58
YES
22.98
177.5
1.4
248.5
247.0
1.39
YES
35.55
204.5
1.5
306.8
244.5
1.20
YES
21.88
245.0
1.5
367.5
239.0
0.98
YES
29.12
278.8
1.0
278.8
232.9
0.84
NO
292.3
1.0
292.3
230.1
0.79
NO
312.5
1.0
312.5
225.6
0.72
NO
335.0
1.0
335.0
220.1
0.66
NO
362.0
1.0
362.0
213.1
0.59
NO
393.5
1.0
393.5
204.4
0.52
NO
434.0
1.0
434.0
192.7
0.44
NO
483.5
1.0
483.5
178.3
0.37
NO
528.5
1.0
528.5
165.4
0.31
NO
573.5
1.0
573.5
153.0
0.27
NO
618.5
1.0
618.5
141.3
0.23
NO
663.5
1.0
663.5
130.4
0.20
NO
_____________________________________________
249016848.xlsx.ms_office
178.73
288.26
mm
110
mm
109.54
___________________________________________
Settlement-center
___________________________________________
Sheet 6 of 8
Client Contract
No.:
Project Title:
Settlement Calculation at center under of Crude
Condensate Storage Tank Foundation
Title:
Job No.
Prepared By:
TR
Checked By:
RT
Doc No.:
5.0) References
1 From Soil Mechanics by R.F Craig, 7th Edition
2 From "Shallow Foundations - Bearing Capacity & settlements" by Das B M, 2nd Edition