No abstract

In view of the recent announcements by the USA government permitting further drilling in certain areas offshore Alaska and the steady increase in oil prices, it may be again possible to predict that Arctic oil and gas development and transportation projects are imminent. The challenges associated with design and operation of Arctic exploration and production installations are many and have been exhaustively discussed in the past. This paper will summarize these challenges and show how a significant number of them have been addressed in the past and how new technologies may be implemented to alleviate the remaining challenges. In the late seventies and early eighties extensive Arctic R&D work was carried out. A small sample of this work includes the Arctic Pilot Project, the CANMAR icebreaker research program with full scale testing, the Tarsuit artificial island, the Hans island ice load monitoring programs, and the Canadian Coast Guard development of the Canadian Arctic Shipping Pollution Prevention Regulations (CASPPR). The R&D work carried out in Finland and Russia is also discussed. This paper demonstrates how the available results from these projects may be applied in the development of current and new rules and standards. The issues that are still outstanding are highlighted and proposals for possible resolution thereof are made. A presentation of ongoing work for the development of new DNV design guidelines on ice-structure interaction will be presented. The work will be completed in 2011 or early 2012. The project will be based on the new ISO 19906 standard, and will cover both fixed and floating installations. The paper also describes results from a recently completed real-time ice load monitoring program onboard an icebreaking vessel and shows correlation with proposed formulations.

The main focus of the paper is to describe a framework for formulating design ice loads for an Arctic drilling platform using probabilistic methods. Particular attention has been paid to the issues of data and model uncertainty and possible effects due to climate change. We apply the methodology to a concept developed by StatoilHydro as a potential configuration for relatively shallow water depths. To minimize and resist ice loads, the concept utilizes a strong central leg and a combined template and platform docking foundation piled to the sea floor. The governing ice loads are due to the action of first-year ice ridges. The ice loads obtained by the probabilistic approach are compared with deterministic model results. A modification of the model is tested for various assumptions related to global warming and its effects on reduced ice coverage and thickness.