Response of subsea pipelines to ice-induced geohazards

海底管道是纽芬兰近海和其他恶劣海洋环境中油气田开发的关键要素和组成部分。在冷水中，海底管道面临的最大风险之一是海床上的冰引起的冲刷。保护管道，如挖沟或埋藏管道，是避免与冰凿直接相互作用的最实际和最具成本效益的解决方案。然而，为了获得足够的管道保护水平，估计最小可靠埋深，并利用裸露的管道来消除巨大的海底开挖成本，是具有挑战性的技术问题。答案依赖于对复杂的冰刨过程的更好理解，特别是对亚刨土变形的了解。在过去的20年里，人们进行了大量的研究，以促进该行业对冰凿的理解。但是，在冰凿问题上仍然存在许多不确定性，这些问题最近被确定为知识差距(NRC-PERD(2014)，BSEE-WGK(2015)。这项研究计划的重点是解决关键的知识差距，并提高我们对恶劣海洋环境中海底管道变形的理解。提出的研究方案的方法在于高级数值研究和离心机模型试验，目标是评估管道对大变形海底地质灾害的响应。该项目涉及一个由17名HQP组成的团队(6名博士、4名孟加拉人、4名文凭和3名PDF)。这些成果给行业合作伙伴Wood Group带来了直接的好处，并使其有能力为纽芬兰的Grand Banks等冰凿环境安全设计海上管道。Wood Group将通过改进冰凿环境中管道的设计和生命周期完整性管理，将结果整合到其运营中。因此，拟议的研究计划与Wood Group和其他在离岸行业这一领域工作的公司面临的技术挑战和需求很好地结合在一起。通过这一研究计划，我们的团队和行业合作伙伴将能够在工程软件工具中实施和应用结果，这些工具用于分析和设计纽芬兰和其他地方的冰凿环境下的海上管道。

Subsea pipelines are a key element and component of oil and gas field developments in offshore Newfoundland and other harsh ocean environments. One of the most significant risks to subsea pipelines in cold waters is ice-induced scour in the seabed. Protection such as trenching or burial of the pipeline is the most practical and cost effective solution to avoid direct interaction with an ice gouge. However, estimating the minimum reliable burial depth to obtain a sufficient level of pipeline protection, and using exposed pipelines to eliminate the large subsea trenching costs, are challenging technical problem. The answers rely on a better understanding of complex ice gouging processes and particularly subgouge soil deformation. In the past 20 years, numerous research studies have been conducted to advance the industry's understanding of ice gouging. But there are still many uncertainties in ice gouge problems that were recently identified as knowledge gaps (NRC-PERD (2014), BSEE-WGK (2015). This research program focuses on addressing key knowledge gaps and improving our understanding of subsea pipeline deformation in harsh ocean environments. The approach of the proposed research program lies in both advanced numerical studies and centrifuge model testing, by targeting the assessment of the pipeline response to large deformation subsea geohazards. The project involves a team of 17 HQP (6 PhD, 4 MEng, 4 BEng, and 3 PDF). The outcomes have direct benefits for the industry partner, Wood Group, and its ability to safely design offshore pipelines for ice-gouge environments like Newfoundland's Grand Banks. Wood Group will integrate the outcomes into its operations by improving the design and life cycle integrity management of pipelines in ice-gouge environments. The proposed research program is therefore well aligned with the technical challenges and needs faced by Wood Group and others working in this sector of the offshore industry. Through this research program, our team and industry partner will be able to implement and apply the results in engineering software tools used to analyze and design offshore pipelines for ice-gouge environments in Newfoundland and elsewhere.