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.

螺丝桩是加拿大深层基础的创新类型。加拿大的螺丝桩行业代表了一个潜在的市场，规模为1B美元。加拿大的螺丝桩行业支持加拿大的基础设施建设，采矿部门，铁路和北极发展。螺丝桩已被采用给加拿大的基础手册和技术指南。尽管广泛使用螺丝桩，但仍然可以发现几种缺陷。工程师或研究人员尚不清楚控制螺钉桩故障的因素。当前的螺丝桩设计方法可能需要改进。 拟议的计划将解决与土壤螺旋桩相互作用有关的基本问题。该计划由三个主要项目组成。在第一个项目中，将在实验室进行土壤反应和孔隙水反应，以安装在各种土壤类型的螺钉中。将测量各个尺寸的螺钉堆的轴向和侧向电阻；将使用粒子图像速度测定技术来量化受轴向载荷的螺钉桩周围的土壤变形模式。第一个项目的目的是解决详细的土壤螺钉桩相互作用，该桩相互作用可进一步用于了解螺丝桩的故障模式并协助螺钉桩设计。在第二个项目中，将在实验室开发和测试旋转渗透仪（RPT）。该项目的目标是支持螺丝桩的直接设计方法，并为岩土工程现场调查提供新工具。 RPT可以被认为是由轴和螺旋组成的微型螺钉桩。在RPT渗透过程中收集的安装扭矩轮廓和孔隙压力可以支持土壤特性和行为类型的解释。与其他调查技术向下驱动轴的其他调查技术不同，RPT将轴拧入地面以进行现场调查。 该计划的第三个项目将验证RPT在艾伯塔大学农场的现场表现。将源自RPT的土壤特性和桩电阻与先前确定的实际值进行比较。 RPT将在常规调查方法上具有多个优势，并且可以在螺丝桩行业中找到独特的利基市场。 该计划将培训两名博士生，一名MSC学生和几名本科生。拟议程序的结果将改善当前的螺丝桩设计方法，并开发一种用于岩土现场调查的创新技术。该研究计划将使加拿大在螺丝桩行业和现场调查中保持世界领先地位。