Page 84 - Pipelines and Risers

BucWingKollapse of Deepwater Metallic Pipes 57

eIement results and analytical solutions presented in figure 3.7-3.10 give good reasons to
expect that the finite element model also will give reliable predictions for combined loads.

X = Wresutts
_- -
- Analytical

10 M 36 40 50

Figure 3.7 Moment capacity as a function of diameter over wall thickness for a pipe subjected to pure
bending.

10’
4 3
= FErsults -
FErsults
=
-- = Analytical
-- = Analytical
3.5

1-
0.5
10 20 30 40 50 BO

Figure 3.8 Limit longitudinal force as a function of diameter over wall thickness for a pipe subjected to
pure longitudinal force.

x = FEresults
-
_- - Haagsm
- - - = Timoshenko

10 20 30 40 50 BO

Figure 3.9 Collapse pressure as a function of diameter over wall thickness for a pipe subjected to pure
external overpressure. Initial out-of-roundness fo equal to 1.5%.