Based on new methodological developments in the area of risk-based inspection planning (RBI) for structural components subject to fatigue degradation, the present paper presents a unified approach to risk-based inspection planning for offshore facilities comprising components and systems of both the structural and process type. Suggestions are given for the formulation of acceptance criteria on component level based on overall facility acceptance criteria in terms of risk to personnel, environmental risks and economical risks. The methodology facilitates a generic modeling of fatigue and corrosion degradation for both structural and process type components. Furthermore, special considerations are given to the important aspect of updating of inspection plans when degradation has been observed. The different aspects of RBI for steel components subject to fatigue and corrosion degradation are illustrated on an example considering RBI for the components of a tripod well-head platform.

1.
Madsen, H.O., Sørensen, J.D., and Olesen, R., 1989, “Optimal Inspection Planning for Fatigue Damage of Offshore Structures,” Proc. ICOSSAR 89, San Francisco, CA, pp. 2099–2106.
2.
Lotsberg, I., and Sigurdsson, G., and Wold, P.T., 1999, “Probabilistic Inspection Planning of the Åsgaard A FPSO Hull Structure With Respect to Fatigue,” Proc. OMAE99, New Foundland, Canada.
3.
Faber, M.H., Berge, H.E., Tiller, I., and Hall, M.E., 1999, “Reliability Based Assessment of Offshore Concrete Structures Subject to Chloride Ingress,” Proc. OMAE99, Newfoundland, Canada.
4.
Rackwitz
,
R.
,
2000
, “
Optimization–The Basis for Code-Making and Reliability Verification
,”
Structural Safety
,
22
(
1
), pp.
27
60
.
5.
Nathwani, J.S., Lind, N.C., and Pandey, M.D., 1997, Affordable Safety by Choice: the Life Quality Method, Institute for Risk Research, University of Waterloo, Waterloo, Canada.
6.
Faber, M.H., Engelund, S., Sorensen, J.D., and Bloch, A., 2000, “Simplified and Generic Risk Based Inspection Planning,” Proc. OMAE 2000, New Orleans.
7.
Strutt, J.E., Allsopp, A., Newmann, D., and Trille, C., 1996, “Reliability Prediction of Corroding Pipelines,” Proc. OMAE 1996, Vol. V, Florence, Italy, pp. 495–509.
8.
Melchers, R.E., 1994, Pitting Corrosion in Marine Environments, Research Report, University of Newcastle–Department of Civil Engineering.
9.
Straub, D., and Faber, M.H., 2000, “Generic Risk Based Inspection Planning for Components Subject to Corrosion,” Proc. ESRA Workshop on Risk Based Inspection Planning, Zu¨rich.
10.
Turnbull
,
A.
,
1993
, “
Review of Modelling of Pit Propagation Kinetics
,”
Br. Corros. J., London
,
28
(
4
), pp.
297
308
.
11.
Laycock
,
P.J.
,
Cottis
,
R.A.
, and
Scarf
,
P.A.
,
1990
, “
Extrapolation of Extreme Pit Depths in Space and Time
,”
J. Electrochem. Soc.
,
137
(
1
), pp.
64
69
.
12.
Finley
,
H.F.
,
1967
, “
An Extreme-Value Statistical Analysis of Maximum Pit Depths and Time to First Perforation
,”
Corrosion (Houston)
,
23
(
4
), pp.
83
87
.
13.
Ahammed, M., and Melchers, R.E., 1999, Atmospheric Corrosion of Mild and Low Alloy Steel, Research Report, University of Newcastle–Department of Civil Engineering.
14.
Faber
,
M.H.
, and
Sørensen
,
J.D.
,
2002
, “
Indicators for Assessment and Inspection Planning
,”
Structural Safety
,
24
(
2–4
), pp.
377
396
.
15.
Goyet, J., Straub, D., and Faber M.H., 2002, “Risk Based Inspection Planning–Methodology and Application to an Offshore Structure,” Revue Franc¸aise de Ge´nie Civil, Hermes, Paris, 6(3), pp. 489–503.
You do not currently have access to this content.