Reliability Analysis of Tubular Joints of Offshore Platforms in Malaysia

The oil and gas industry has moved towards Load and Resistance Factor Design through API RP2A - LRFD and the recently published international standard, ISO-19902, for design of fixed steel offshore structures. The ISO 19902 is intended to provide a harmonized design practice that offers a balanced structural fitness for the purpose, economy and safety. As part of an ongoing work, the reliability analysis of tubular joints of the jacket structure has been carried out to calibrate the load and resistance factors for the design of offshore platforms in Malaysia, as proposed in the ISO. Probabilistic models have been established for the load effects (wave, wind and current) and the tubular joints strengths. In this study the First Order Reliability Method (FORM), coded in MATLAB Software has been employed to evaluate the reliability index of the typical joints, designed using API RP2A - WSD and ISO 19902.




References:
[1] Idrus, A.B., Narayanan, S. P., Hamid, M. F. A. , Cossa, N. J. ,
Nizamani, Z., Resistance Parameters Statistics for Jacket Platforms in
Offshore Malaysia, Proceedings of the Twenty-first (2011) International
Offshore and Polar Engineering Conference Maui, Hawaii, USA, June
19-24, 2011,226-232 , ISBN 978-1-880653-96-8 (Set); ISSN 1098-6189
(Set); www.isope.org
[2] Nowak, A. S. and Collins, K.R., Reliability of Structures, McGraw-Hill,
2000.
[3] ISO 2394:1998, General principles on Reliability for Structures.
International Standards Organization, International Organization
Standardization, 1998.
[4] ISO 19902:2007, Petroleum and Natural Gas Industries - Fixed Steel
Offshore Structures, 1st Edition, International Organization
Standardization, 2007.
[5] Bomel Ltd ÔÇÿÔÇÿComponent-Based Calibration of North West European
Annex Environmental Load Factor to ISO Fixed Steel Offshore
Structures Code 19902,--, 2003, Maidenhead, UK.
[6] Duan, Z.D., Zhou,D.C., Ou J.P., Calibration of LRFD format for steel
jacket platforms in China Offshore Area(1) Statistical Parameters of
loads and resistances, China Ocean Engineering, 2006, 20(1) 1-14
[7] Duan, Z.D., Zhou,D.C., Ou J.P., Calibration of LRFD format for steel
jacket platforms in China Offshore Area(2):Load, resistance and Load
Combination Factors, China Ocean Engineering, 2006, 20(2) 199-212
[8] Tarp-Johansen NJ , Partial Safety and Characteristic Values for
Combined Extreme Wind and Wave Load Effects, Wind Energy
Department , Riso National Laboratory 2004
[9] Idrus, A.B., Narayanan, S. P., Hamid, M. F. A. , Nizamani, Z, Cossa, N.
J. , Selection of Environmental Parameters for Offshore Jacket Platform
Design in Malaysia, Advances in Steel and Aluminum Structures(Proc.
ICSAS 2011) , 383-387, ISBN: 978-981-08-9247-0
[10] Theophanatos, A. , Wickham, A. H. S., Modelling Of Environmental
Loading For Adaptation Of API RP 2A - Load And Resistance Factor
Design To UK Offshore Structural Design Practice, Proc. Instn Civ.
Engrs Wat.. Marit. &Energy, 1993, 101, Dec., 195-204
[11] GUMBEL, E.J., 1958. Statistics of Extremes. Columbia University
Press, New York.
[12] Neelamani, S.; Al-Salem, K. and Rakha, K., 2007. Extreme waves in the
Arabian Gulf. Journal of Coastal Research, SI 50 (Proceedings of the 9th
International Coastal Symposium), 322 - 328. Gold Coast, Australia,
ISSN 0749.0208
[13] Tan, Chun Chai (2005) A numerical analysis of fixed offshore structure
subjected to environmental loading in Malaysian water. Master-s thesis,
Universiti Teknologi Malaysia, Faculty of Mechanical Engineering
[14] API RP2A-WSD:2005, Recommended Practice for planning, design and
constructing fixed offshore platforms - Working Stress Design, 21st
Edition, American Petroleum Institute, 2005
[15] Chakrabarti, S. K., Hydrodynamics of Offshore Structure, WIT Press,
UK 1987.
[16] Donders, S., Van de Peer, J. and Schueremans, L. "Structural Reliability
Analysis of a Car Front Cradle with Multiple Design Criteria"
Postdoctoral Research, KU Leuven, Belgium, 2004;
http://www.kuleuven.ac.be/bwk/materials/Research/index.htm
[17] Galambos, T. V., Load and Resistance Factor Design, National
Engineering Conference by AISC, 1981
[18] Choi, S.K., Grandhi, R., Canfield, R. A., Reliability-based Structural
Design 1st Edition, Springer, 2007
[19] Melchers RB. Structural Reliability Analysis and Prediction. 2nd
Edition; Wiley,Chichester, UK, 1999.