Towards the Innovation of Screw Piles: Lab Pile Testing and Rotary Penetrometer Development

迈向螺旋桩的创新：实验室桩测试和旋转贯入仪开发

• 批准号: RGPIN-2020-05369
• 负责人: Deng, Lijun
• 金额: $ 3.13万
• 依托单位: University of Alberta
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2020
• 资助国家: 加拿大
• 起止时间: 2020-01-01 至 2021-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=716447
• 关键词: Towards; Innovation; Screw; Piles; Lab

Screw piles are an innovative type of deep foundations in Canada. The screw pile industry of Canada represents a potential market at the scale of $1B. The screw pile industry of Canada supports the infrastructure construction, mining sector, railway, and Arctic development in Canada. Screw piles have been adopted to foundation manual and technical guides of Canada. Despite wide use of screw piles, several deficiencies can still be identified. The factors that governs the failure of screw piles are not clear to engineers or researchers. The current design methods for screw piles may need to be improved. The proposed program will address the fundamental questions related the soil-screw pile interaction. The program consists of three major projects. In the first project, the soil reaction and pore water response to screw piles installed into various soil types will be conducted in the laboratory; the axial and lateral resistance of screw piles of varying dimensions will be measured; the soil deformation pattern around screw piles subjected to axial loading will be quantified using the Particle Image Velocimetry technique. The objective of the first project is to address the detailed soil-screw pile interaction that can further be used to understand failure modes of screw piles and assist in the screw pile design. In the second project, a rotary penetrometer (RPT) will be developed and tested in the laboratory. The objectives of this project are to support the direct design method of screw piles and offer a new tool for geotechnical site investigation. RPT may be considered as a miniature screw pile consisting of a shaft and helix. The installation torque profiles and pore pressure collected during RPT penetration can support the interpretation of soil properties and behaviour types. Unlike other investigation techniques that drive a shaft downwards, RPT screws a shaft into ground for the site investigation purpose. The third project of this program will validate the performance of RPT in the field located on the farm at the University of Alberta. Soil properties and pile resistance, derived from RPT, will be compared with actual values that had been previously determined. RPT will have several advantages over conventional investigation methods and can find a unique niche in the screw pile industry. The program will train two PhD students, one MSc student, and several undergraduate students. The outcomes of proposed program will improve the current design approaches for screw piles and develop an innovative technique for geotechnical site investigation. The research program will make Canada maintain a world leader in the screw pile industry and site investigation.

螺旋桩是加拿大深基础的一种创新类型。加拿大的螺旋桩行业代表着1B规模的潜在市场。加拿大的螺旋桩产业支撑着加拿大的基础设施建设、采矿业、铁路和北极开发。螺旋桩已被加拿大基础手册和技术指南采用。尽管螺旋桩被广泛使用，但仍然可以发现一些缺陷。工程师或研究人员尚不清楚影响螺旋桩失效的因素。目前的螺旋桩设计方法可能需要改进。 拟议的计划将解决与土-螺旋桩相互作用相关的基本问题。该计划由三个主要项目组成。第一个项目将在实验室进行不同土壤类型中安装的螺旋桩的土壤反应和孔隙水响应；测量不同尺寸螺旋桩的轴向和侧向阻力；受到轴向载荷作用的螺旋桩周围的土壤变形模式将使用粒子图像测速技术进行量化。第一个项目的目标是解决详细的土壤-螺旋桩相互作用，可进一步用于了解螺旋桩的破坏模式并协助螺旋桩设计。在第二个项目中，将开发旋转贯入仪（RPT）并在实验室进行测试。该项目的目标是支持螺旋桩的直接设计方法，并为岩土现场勘察提供新工具。 RPT可以被认为是由轴和螺旋线组成的微型螺旋桩。 RPT 穿透过程中收集的安装扭矩曲线和孔隙压力可以支持对土壤特性和行为类型的解释。与其他向下驱动轴的勘察技术不同，RPT 将轴拧入地面以进行现场勘察。 该计划的第三个项目将验证 RPT 在阿尔伯塔大学农场现场的性能。由 RPT 得出的土壤特性和桩阻力将与之前确定的实际值进行比较。与传统调查方法相比，RPT 具有多种优势，可以在螺旋桩行业中找到独特的定位。 该项目将培养两名博士生、一名硕士生和多名本科生。拟议计划的成果将改进当前的螺旋桩设计方法，并开发岩土现场调查的创新技术。该研究计划将使加拿大在螺旋桩行业和现场调查方面保持世界领先地位。