Laboratory investigation of screw micropiles as foundations in the Arctic

加拿大北极地区的基础设施在很大程度上依赖于深地基的性能。在北极地区使用的传统地基可能存在一些风险，例如过大的长期沉降和夏季温暖的永久冻土中地基的脆弱性。ARKK工程公司是一家位于阿尔伯塔省的咨询公司，对重新设计适合北极的地基有着浓厚的兴趣。作为顾问，ARKK可以为北极选择最合适的基础类型。在过去的几十年里，ARKK研究了几种新兴的地基类型，并建议螺旋微桩可能为北极的地基提供一个可行的解决方案。然而，在这种新兴的桩型能够实际应用之前，应该解决长期沉降和在温暖的永久冻土中的工程行为问题。因此，ARKK和阿尔伯塔大学的研究人员建议通过进行实验室测试来研究北极地区螺旋微桩的性能。本文的研究目标是：1)研究桩的长期蠕变沉降；2)研究了夏季高温冻土条件下桩作为冻土冻结工具的有效性。本研究将培养两名岩土工程研究生。该项目的研究成果将极大地利用ARKK在寒冷地区基础设计方面的知识，并为加拿大的北极地区带来一种精心设计的基础类型。

The infrastructure of Canada's Arctic regions is largely dependent on the performance of deep foundations. The traditional foundations used in the Arctic may pose several risks, such as the excessively large long-term settlement and the vulnerability of the foundations in warm permafrost during the summer. ARKK Engineering Corp., a consulting company located in Alberta, has a strong interest in re-designing foundations that are suitable for the Arctic. As a consultant, ARKK can choose the most appropriate foundation type for the Arctic. ARKK has chased several emerging foundation types in the past decades and suggest that the screw micropile may offer a viable solution to the foundations in the Arctic. However, before this emerging pile type could be practically used, the concerns with the long-term settlement and the engineering behaviour in warm permafrost should be addressed.ARKK and researcher at the University of Alberta therefore propose to investigate the performance of screw micropiles in the Arctic by conducting laboratory tests. The objectives of the proposed research are: 1) to investigate the long-term creep settlement of the pile; and 2) to study the efficiency of the pile as a ground freezing tool in warm permafrost during the summer. The proposed research will train two graduate students in geotechnical engineering. Findings of the project will significantly leverage ARKK's knowledge in cold regions foundation design and bring a well-engineered foundation type to Canada's Arctic.