Effects of Foundation Models on Jack-up Site Assessment

ZHANG Jian, TANG Wenxian, SU Shijie, SU Shijie, GAO Chao

Abstract


In order to investigate effects of different foundation models on jack-up site assessment, numerical simulation of a jack-up is presented based on fix joint, pin joint, linear springs and elastic-plastic model. The hull, leg, hull-leg connection is modelled using equivalent beam, beam element, spring element, respectively. Environmental loads, such as steady current, wind, wave, inertial load and buoyancy, are also included in the numerical model. Static and natural frequency extraction analysis of the jack-up is then performed in elevated condition. Finally, static and natural response rules are proposed for the four foundation models. The results show that, the horizontal hull displacement, maximum leg stress, loads on spudcan B and horizontal moment on spudcan A decrease as the rotational stiffness increases, while the natural frequency, vertical load and horizontal load on spudcan A increase with the increasing rotational stiffness. And the responses for elastic-plastic model are close to the pin joint. The proposed modelling and analyzing method is effective and reliable, which could provide guidance for jack-up development and assessment.

Key words: Jack-up; Fix joint; Pin joint; Linear springs; Elastic-plastic model; Numerical simulation


Keywords


Jack-up; Fix joint; Pin joint; Linear springs; Elastic-plastic model; Numerical simulation

References


SNAME. (2008). Technical & Research Bulletin 5-5A Recommended Practice for Site Specific Assessment of Mobile Jack-up Units. New Jersey: Society of Naval Architects and Marine Engineers.

Mike, J. R. H., & John, J. S. (2011). Jack-up Site Assessment – the Voyage to an ISO. In Proceedings of the ASME 2011 30th International Conference on Ocean, Offshore and Arctic Engineering (pp. 713-724). doi :10.1115/OMAE2011-50056

Cassidy, M. J., Martin, C. M., & Houlsby, C. T. (2004). Development and Application of Force Resultant Models Describing Jack-up Foundation Behaviour. Marine Structures, 17(3-4), 165-193.

Gaudin, C., Cassidy, M. J., Bienen, B., & Hossain, M. S. (2011). Recent Contributions of Geotechnical Centrifuge Modelling to the Understanding of Jack-up Spudcan Behaviour. Ocean Engineering, 38(7), 900-914.

Cassidy, M. J. (2011). Offshore Foundation Systems for Resource Recovery: Assessing the Three-Dimensional Response of Jack-up Platforms. KSCE Journal of Civil Engineering, 15(4), 623-634.

Det Norske Veritas (2011). Structural Design of Offshore Units (WSD Method). Retrieved from exchange.dnv.com/publishing/Codes/download.asp?url=2011-04/os-c201.pdf

LI, H. T., YANG, Q. X., & LI, Y. (2010). Study on General Performance of Jack-up Under Elevated Condition. China Ocean Engineering Society, 23(3), 577-584.

Azadi, M. R. E. (2010). Influence of Spud-can-soil Interaction Modelling and Parameters on the Reliability Index of Neka Drilling Jack-up Platform. Journal of Offshore Mechanics and Arctic Engineering, 132(3), 1-13.


Bienen, B., & Cassidy, M. J. (2009). Three-Dimensional Numerical Analysis of Centrifuge Experiments on a Model Jack-up Drilling Rig on Sand. Canadian Geotechnical Journal, 46(2), 208-224.


Bienen, B., Cassidy, M. J., & Gaudin, C. (2009). Physical Modelling of the Push-over Capacity of a Jack-up Structure on Sand in a Geotechnical Centrifuge. Canadian Geotechnical Journal, 46(2), 190-207.


CCS. (2005). Rules for the Classification and Construction of Mobile Offshore Platforms. Beijing: People’s Communications Press.


MSC. (2007). Overall Basic Design for Jack-up. Gusto MSC.


Bienen, B., & Cassidy, M. J. (2006). Advances in the Three-Dimensional Fluid-structure-soil Interaction Analysis of Offshore Jack-up Structures. Marine Structures, 19(2-3), 110-140.


Cassidy, M. J., & Bienen, B. (2002). Three-Dimensional Numerical Analysis of Jack-up Structures on Sand. In Proceedings of the 12th International Offshore and Polar Engineering Conference (pp. 807-814). Retrieved from http://e-book.lib.sjtu.edu.cn/isope2002/pdffiles/Volume2/2125p807.pdf


Simulia. (2010). Abaqus Online Documentation. Retrieved from http://abaqusdoc.ucalgary.ca/v6.9/




DOI: http://dx.doi.org/10.3968%2Fj.ans.1715787020120504.688

Refbacks

  • There are currently no refbacks.


Reminder

If you have already registered in Journal A and plan to submit article(s) to Journal B, please click the CATEGORIES, or JOURNALS A-Z on the right side of the "HOME".

We only use the following emails to deal with issues about paper acceptance, payment and submission of electronic versions of our journals to databases:
caooc@hotmail.com; office@cscanada.net; office@cscanada.org
ans@cscanada.net;ans@cscanada.org

Copyright © Canadian Research & Development Centre of Sciences and Cultures (CRDCSC)
Address:730, 77e AV, Laval, Quebec, H7V 4A8, Canada

Telephone: 1-514-558 6138
Http://www.cscanada.net; Http://www.cscanada.org
E-mail:caooc@hotmail.com; office@cscanada.net