Validation and Extension of Soil Response Framework for Fatigue Analysis of Offshore Wells and Piles
- Arash Zakeri (BP America Inc.) | Hendrik Sturm (Norwegian Geotechnical Institute) | Philippe Jeanjean (BP America Inc.)
- Document ID
- Offshore Technology Conference
- Offshore Technology Conference, 6-9 May, Houston, Texas
- Publication Date
- Document Type
- Conference Paper
- 2019. Offshore Technology Conference
- piles, p-y curves, fatigue analysis, integrity assessment, conductor
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A soil response framework for use in fatigue assessment of offshore wells and piles is presented. The framework covers clay and sand soil types. It was developed through comprehensive series of physical testing and numerical simulations. It hinges on determination of the unload-reload secant stiffness response of soils degraded under cyclic fatigue loading and reaching a steady-state condition. The framework comprises two calibrated approaches: spring-only and spring-dashpot. The latter is more appropriate when dynamic response of a structure needs to be more accurately determined through for time-domain analysis. Efficacy and validation of the framework are demonstrated through three (3) field monitoring programs involving offshore wells installed in ground conditions ranging from soft clays typically encountered in deepwater to layered sands and clays in shallow waters. Further validation is provided by presenting results from an extensive laboratory testing program involving nine (9) soil samples taken from various geographical locations against the key relationships of the framework. The laboratory tests were conducted in a novel apparatus developed specifically for obtaining soil resistance–displacement relationship for input to fatigue analysis.
|File Size||2 MB||Number of Pages||26|
Jeanjean, P.,Zhang, Y.,Zakeri, A.,Andersen, K.,Gilbert, R., and Senanayake, A. I. M. J., (2017), "A Framework for Monotonic P-Y Curves in Clays (Keynote Lecture)," Offshore Site Investigation & Geotechnics Committee 8th International Conference "Smarter Solutions for Future Offshore Developments", London, UK.
Russo, M.,Zakeri, A.,Kuzmichev, S.,Grytøyr, G.,Clukey, E., and Kebadze, B. E., (2016), "Measured Wellhead Loads During Drilling Operations. Benchmarking of Wellhead Fe Model Vs Field Data Considering Different Soil Models" Journal of Offshore Mechanics and Arctic Engineering, American Society of Mechanical Engineers (ASME), 138.
Myhre, E.,Eilertsen, L. E.,Russo, M.,Johansen, F.,Hart, C., and Kalhovd, T. J., (2015), "Successful Real Time Instrumentation of the Conductor and Surface Casing of an Exploration Subsea Well in the North Sea to Measure the Actual Loads Experienced During Drilling Operations," Offshore Technology Conference (OTC), Houston, Texas, USA, OTC Paper 25770.