Engineered Thermal Transition Zones for Enhanced Geotechnical Foundation Systems

用于增强岩土基础系统的工程热过渡区

• 批准号: 1634493
• 负责人: David Frost
• 金额: $ 26.12万
• 依托单位: Georgia Tech Research Corporation
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-06-01 至 2018-11-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1634493&HistoricalAwards=false
• 关键词: Engineered; Thermal; Transition; Zones; Enhanced

Working with an industry partner, this research will develop a new design configuration and installation methodology for heat exchange thermal piles which deviates from the current approach of internally modifying conventional structural piles. This will be achieved by replacing the conventional system with a transition zone that is manufactured in-place between a conventional structural pile and the surrounding soil to significantly increase thermal performance of the pile system. Proof-of-concept modeling has shown the potential for dramatic increases in the thermal performance of an energy pile that can make them a more feasible renewable and sustainable energy alternative for heating and cooling buildings, including single and multi-family residential buildings. The study will use the new insight from the proof-of-concept modeling as the motivation for laboratory and field scale physical and numerical testing. The broader impacts of being able to dramatically alter the performance and efficiency of thermal pile systems has significant implications on global heating and cooling needs in both developed and developing countries, and can contribute to reducing greenhouse gas emissions. This research is very much aligned with the concept and philosophy of sustainable infrastructure, and encourages a systematic approach to evaluating alternative approaches across the key dimensions most likely to influence system performance including environmental, societal and economic impact, as well as technical factors. Projects based on this research will be developed for the Georgia Tech class "Sustainable Subsurface Infrastructure."In order to better understand the various factors influencing thermal performance of energy piles and to optimize heat transfer characteristics, a series of tasks will build on the insights derived during the proof-of-concept studies. The focus of this investigation is to not only to study the problem in a controlled lab environment, but also to develop practical methodologies for utilization of the results in designing and installing thermally optimized energy piles. To achieve this, the project will first design, fabricate and utilize a laboratory scale apparatus to test model engineered transition zone piles with different soil conditions and different boundary conditions. The tests will be used to validate additional numerical simulations that extend the findings of the original proof-of-concept numerical model studies to design prototype full scale field systems. Working with an industry partner, a full-scale field system will be installed and monitored during a series of trials to assess both the initial response as well as the longer term performance of the system as heating and cooling cycles are applied to the system. The installation method to be used in the field involves the strategic repurposing of existing equipment to allow a staged installation procedure of the new thermal pile configuration. This has important implications for the adoption of the method in practice. Upon completion of the full scale field testing, a design methodology that can be used for future installations in a variety of subsurface conditions with engineered thermal transition zones of different dimensions will be developed.

这项研究将与一家行业合作伙伴合作，开发一种新的热交换热桩的设计配置和安装方法，与目前对传统结构桩进行内部修改的方法有所不同。这将通过在传统结构桩和周围土壤之间就地制造过渡区来取代传统系统来实现，以显著提高桩系统的热性能。概念验证模型表明，能量堆的热性能有可能大幅提高，使其成为供暖和制冷建筑物(包括单户和多户住宅)更可行的可再生和可持续能源替代方案。这项研究将使用概念验证建模的新见解作为实验室和现场规模物理和数值测试的动机。能够显著改变热堆系统的性能和效率的广泛影响对发达国家和发展中国家的全球供暖和制冷需求都有重大影响，并有助于减少温室气体排放。这项研究非常符合可持续基础设施的概念和理念，并鼓励以系统的方式评估最有可能影响系统绩效的关键方面的替代办法，包括环境、社会和经济影响以及技术因素。基于这项研究的项目将为佐治亚理工学院的“可持续地下基础设施”课程开发。为了更好地了解影响能量堆热性能的各种因素并优化热传递特性，将在概念验证研究期间获得的见解基础上开展一系列任务。这项研究的重点不仅是在受控的实验室环境中研究这一问题，而且还为了在设计和安装热优化能量堆时利用结果开发实用的方法。为了实现这一目标，该项目将首先设计、制造和利用实验室规模的设备来测试不同土壤条件和不同边界条件下的工程过渡区桩模型。这些测试将被用来验证额外的数值模拟，这些数值模拟将最初的概念验证数值模型研究的结果扩展到设计全尺寸现场系统的原型。将与一个行业伙伴合作，在一系列试验期间安装和监测一个全尺寸的现场系统，以评估该系统在加热和冷却循环使用时的初步反应和长期性能。现场使用的安装方法包括战略性地重新调整现有设备的用途，以便能够分阶段安装新的热堆配置。这对该方法在实践中的应用具有重要意义。在完成全面的现场测试后，将制定一种设计方法，可用于未来在各种地下条件下安装不同尺寸的工程热过渡区。

项目成果

Suction and thermal conductivity of unsaturated loess from Northern France

法国北部非饱和黄土的吸力和导热系数

• 发表时间: 2018
• 期刊: UNSAT 2018
• 作者: Nguyen, V

Water retention and thermal conductivity of a natural unsaturated loess

• DOI: 10.1680/jgele.17.00037
• 发表时间: 2017-11
• 期刊: Geotechnique Letters
• 影响因子: 2.1
• 作者: V. Nguyen;H. Heindl;Jean-Michel Pereira;A. Tang;J. Frost