Development of algorithms for the forces associated with flexural failure of ice

海上石油和天然气储量的勘探和生产正被越来越往北推进，进入季节性或全年都有冰盖的水域。同时，这些资源的开发要求近海结构能够承受目前的环境条件，同时保持碳氢化合物气田开发的经济性。冰力往往是近海结构的极限设计条件，因此必须对其有充分的了解，并有办法在不过分保守的情况下确定这些力。这项研究的目标是开发一个经过验证的冰对锥形近海结构弯曲破坏的模型。这项研究将建立在前人工作的基础上，这些工作已经产生了一种新的冰对锥形结构弯曲破坏的算法，但仍然不能完全模拟冰与结构之间相互作用的所有三维方面，特别是冰碎石堆。这项研究将引入一种创新的新方法来模拟瓦砾堆，以更准确地评估移动瓦砾堆所需的力。这项研究还将从两个方面解决不确定性问题：模拟负荷和测量负荷之间的比较，后者在看似相似的条件下表现出相当大的分散性；以及将确定性算法扩展到考虑基本自变量中的不确定性的概率模型。最后，该模型还将被扩展以允许对多年冰的相互作用进行建模。拟议的研究将对理解和推进冰与锥形结构的相互作用的建模做出重要贡献。这对于加拿大北极近海石油和天然气储量的安全和经济开发至关重要。

Exploration and production of offshore oil and gas reserves are being pushed further and further north into waters that are exposed to ice cover on a seasonal or year-round, basis. Concurrently, the development of these resources requires offshore structures that can withstand the environmental conditions present while maintaining the economics of the hydrocarbon field development. Ice forces are often the limiting design condition for the offshore structure and thus it is imperative that these be well-understood and that there be means available to determine these forces without undue conservatism. The objective of the proposed research is the development of a validated model for the flexural failure of ice against conical offshore structures.The research will build on previous work that has resulted in a new algorithm for the flexural failure of ice against a conical structure but which still does not fully model all the three-dimensional aspects of the interaction between the ice and the structure, in particular the ice rubble pile. The research will introduce an innovative new approach to the modeling of the rubble pile to provide a more accurate assessment of the force required to displace it. The research will also address the issue of uncertainty in two aspects: the comparison between modeled and measured loads, where the latter show considerable scatter for seemingly like conditions: and the extension of the deterministic algorithm to a probabilistic model that accounts for the uncertainties in the fundamental independent variables. Finally, the model will also be extended to allow for the modeling of interactions with Multi-year ice.The proposed research will contribute significantly to the understanding, and advance the modeling, of ice interactions with conical structures. This is essential for the safe and economical development of offshore oil and gas reserves in the Canadian Arctic.