Geosynthetic Reinforcement in the Mitigation of Pipeline Flotation - Reinforced Soil Engineering: Advances in Research and Practice - page 244

Table 2 Resisting Forces and Buoyancy

H
(cm)

H
(cm)

A
(kN/m)

B
(kN/m)

C
(kN/m)

W
(km/m)

T
(kN/m)

U
(kN/m) Uplifting Test

1 40 — 4.73 0 0 1.27 6.00 9.77 No

30 — 3.82 0 0 1.27 5.09 9.77 Yes

2 30 56.3 3.43 4.32 2.30 1.27 11.32 9.77 No

20 56.3 2.62 1.32 1.54 1.27 9.74 9.77 Yes

3 10 56.3 2.02 4.05 0.86 1.27 11.20 9.77 No

0 56.3 1.11 7.05 0 1.27 9.43 9.77 Yes

4 10 30.0 1.99 2.58 3.07 1.27 8.91 9.77 No

0 30.0 1.09 2.58 2.23 1.27 7.16 9.77 Yes

5 2 10 30.0 0.52 2.11 3.18 1.27 7.08 9.34 No

2 20 30.0 0.24 2.11 2.49 1.27 6.11 8.59 Yes

A: Weight for Region A. B: Weight for Region B. C: Weight for Region C. W: Weight of pipe. T ¼
A þ B þ C þ W: total resisting forces. U: Uplifting force.

The overburden weight contributes significantly to tests 2 and 3 when
compared to test 1. For tests 4 and 5, the overburden load was not present when
the soil above the crown was fully excavated, yet the resistance to flotation was
large. That is, the soil cement block acted as anchor so that the shear resistance of
soil played a major role.

Figure 12 Resisting forces in stability calculation.