Strain concentrations in pipelines with concrete coating: An analytical model
- Statoil, Trondheim (Norway)
This paper describes an analytical model for prediction of strain concentration in field joints (FJ) of concrete coated pipelines during laying. The model is based on establishing the full non-linear moment-curvature curves at a number of cross-sections on the concrete coated part, and in the FJ. Two methods are suggested to apply these curves to calculate the strain concentration in the FJ. The first method consists of integrating the curves to a ``global`` moment-curvature curve for a pipe joint. A strain concentration factor (SCF) can then be calculated, as the ratio between the moment-curvature curve in the FJ and the global moment-curvature curve, for the given load level. The second method, which is more accurate, is based on performing the lay analysis where a section (2--4 pipe joints) is given varying properties. That can be done by dividing each pipe joint into several elements, where each element has its own moment-curvature curve calculated by the analytical model described in this paper. The analytical model is compared to a non-linear FE shell analysis. The results show good agreement. Results from the analytical model also compares well to results from full-scale bending tests of pipelines.
- OSTI ID:
- 205498
- Report Number(s):
- CONF-950695--; ISBN 0-7918-1311-8
- Country of Publication:
- United States
- Language:
- English
Similar Records
Strain concentrations in pipelines with concrete coating full scale bending tests and analytical calculations
Concrete coated submarine pipelines: Further advances in strain concentration at field joints and relevant implications on strain based design