Effects of Ground Movement on Oil and Gas Pipelines and Piles

滑坡在陆上和近海环境中都会发生。与陆上滑坡类似，文献中也报道了许多水下海底滑坡，其中一些大型海底滑坡引发了海啸，如加拿大纽芬兰近海的大浅滩滑坡。海底滑坡还可能破坏安装在海床上用于近海石油和天然气开发的基础设施。引发岸上和近海滑坡的因素很多，但敏感粘土层的存在、河岸附近的脚趾侵蚀、上坡荷载、软化带的形成和地震荷载是本研究的主要焦点。大型滑坡一般是通过破坏面的逐渐发展而开始的，沿破坏面移动的土块数量较多，距离较远。同样，破坏后土体的移动也可能对人类的生活和基础设施造成毁灭性的影响。在这项研究计划中，将发展能够适应如此大的土体变形的数值模拟技术，以研究陆上和近海的滑坡和抛射。此外，位于滑坡区或滑坡区的管道或桩，由于滑动土体传递到这些构筑物上的力，可能会损坏或破坏。将使用土工离心机进行数值分析和物理模拟，以了解管道-土壤和桩-土相互作用的机理，这些机理可用于改进设计准则。纽芬兰纪念大学的四名硕士和五名博士生的研究将得到这笔拨款的支持。

Landslides occur in both onshore and offshore environments. Similar to onshore landslides, many underwater seabed slope failures have been reported in the literature, and some of the large submarine landslides generated tsunami such as the Grand Banks landslide in offshore Newfoundland, Canada. Submarine landslides could also damage infrastructure installed in the seabed for offshore oil and gas development. Various factors could trigger onshore and offshore landslides; however, the existence of sensitive clay layers, toe erosion near the riverbank, upslope loading, formation of weakened zones and earthquake loading are the main foci of the present study. The large-scale landslides generally initiate through progressive development of failure planes along which a number of failed soil blocks displace over a large distance. Similarly, post-failure movement of the failed soil mass, known as ‘runout,’ could also have devastating effects on human life and infrastructure. Numerical modeling techniques, which can accommodate such large deformation of soil, will be developed in this research program to study onshore and offshore landslides and runout. In addition, pipelines or piles located in the landslide areas or runout zones might be damaged or destroyed due to the force transmitted to these structures by the sliding soil mass. Numerical analysis and physical modeling using a geotechnical centrifuge will be performed to understand pipeline-soil and pile-soil interaction mechanisms which could be used to improve design guidelines. Four Masters and five Doctoral candidates’ research will be supported by this grant at Memorial University of Newfoundland.