Prediction Methods of Spudcan Penetration for Jack-up Units

• Published in: China ocean engineering Vol. 26; no. 4; pp. 591 - 602
• Main Author: 张爱霞 段梦兰 李海明 赵军 王建军
• Format: Journal Article
• Language: English
• Published: Heidelberg Chinese Ocean Engineering Society 01.12.2012; Department of Architecture Engineering, Dalian University of Technology, Dalian 116024, China%Offshore Oil/Gas Research Center, China University of Petroleum, Beijing 102249, China%China National Offshore Oil Corporation, Beijing 100010, China%China Oilfield Services Ltd., CNOOC, Langfang 065201, China
• Subjects: China; Coastal Sciences; Deviation; Engineering; Fluid- and Aerodynamics; Guidelines; Marine; Marine & Freshwater Sciences; Numerical and Computational Physics; Ocean engineering; Oceanography; Offshore Engineering; Penetration; Penetration depth; Simulation; Soil (material); Strata; 单位; 工程实践; 操作过程; 深度预测; 渗透; 穿透深度; 自升式; 钻井工程; ISEW, South China Sea; soil resistance; ALE; penetration; jack-up rig; spudcan
• ISSN: 0890-5487; 2191-8945
• DOI: 10.1007/s13344-012-0045-x

Jack-up units are extensively playing a successful role in drilling engineering around the world, and their safety and efficiency take more and more attraction in both research and engineering practice. An accurate prediction of the spudcan penetration depth is quite instrumental in deciding on whether a jack-up unit is feasible to operate at the site. The prediction of a too large penetration depth may lead to the hesitation or even rejection of a site due to potential difficulties in the subsequent extraction process; the same is true of a too small depth prediction due to the problem of possible instability during operation. However, a deviation between predictive results and final field data usually exists, especially when a strong-over-soft soil is included in the strata. The ultimate decision sometimes to a great extent depends on the practical experience, not the predictive results given by the guideline. It is somewhat risky, but no choice. Therefore, a feasible predictive method for the spudcan penetration depth, especially in strata with strong-over-soft soil profile, is urgently needed by the jack-up industry. In view of this, a comprehensive investigation on methods of predicting spudcan penetration is executed. For types of different soil profiles, predictive methods for spudcan penetration depth are proposed, and the corresponding experiment is also conducted to validate these methods. In addition, to further verify the feasibility of the proposed methods, a practical engineering case encountered in the South China Sea is also presented, and the corresponding numerical and experimental results are also presented and discussed.