CAREER: Inspiring a New Paradigm in Geotechnical Design and Education Through an Understanding of Biomimetic Load Transfer in Soils

职业：通过了解土壤中的仿生荷载传递，激发岩土设计和教育的新范式

• 批准号: 1752392
• 负责人: Michelle Bernhardt
• 金额: $ 50万
• 依托单位: University of Arkansas
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2018
• 资助国家: 美国
• 起止时间: 2018-07-01 至 2024-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1752392&HistoricalAwards=false
• 关键词: CAREER; Inspiring; New; Paradigm; Geotechnical

This Faculty Early Career Development Program (CAREER) grant will support research that will advance the fundamental understanding of how loads are transferred through soils, and how biological mechanisms and new construction techniques can improve the use of soil as a building material. Many natural materials have geometrical microstructures which make them stronger and tougher than their base materials. This research will provide the needed knowledge so that these mechanisms can be incorporated in soils using additive manufacturing (i.e. 3D printing) techniques in which soils are "printed" into structural components or cellular patterns to improve their load carrying ability. Bio-inspired structures like the honeycomb have been studied for metals and other solid materials; however, an understanding of the effectiveness of these load transfer mechanisms in particulate materials like soils is lacking. Improving a soil's ability to carry load will result in more sustainable and cost-effective geotechnical practice by reducing the amounts of concrete and other materials needed for a project. The fundamental understanding gained in this project will also move additive manufacturing further towards becoming a viable option for building shelters and other infrastructure in remote and underdeveloped locations, and in disaster relief or war-torn areas. Additionally, this project seeks to promote interdisciplinary education through a new course and the participation and retention of diverse students through activities such as K-12 outreach focused on exploring engineering principles in nature, visual-spatial workshops, and recruitment of high quality researchers through the University's Engineering Career Awareness Program. Hierarchical microstructures give many natural materials strengths which are orders of magnitude greater than their constituents. The research goal of this CAREER grant is to leverage these biomimicry concepts to advance the fundamental understanding of load transfer mechanisms in soil. While researchers have observed benefits for similar bio-inspired designs of metals and composites, a fundamental understanding of the effectiveness of these load transfer mechanisms in brittle particulate materials like soils is needed. Therefore, this grant focuses on: (1) understanding the optimized load carrying mechanisms in nature and mimicking these mechanisms in soils; (2) evaluating the behaviors of bio-inspired soils across the length scales using experimental testing and discrete element method (DEM) modeling; and, (3) investigating additive manufacturing as a means to construct cellular soil fabrics and infrastructure at the field-scale. In addition to the DEM simulations, a topology-based method for optimizing the patterns for a given loading scenario and capturing the resulting behavior is necessary to provide a solution for the many possible geotechnical applications. Laboratory and mid-scale testing of bio-improved soils will also be conducted to assess the feasibility of full-scale implementation of the process.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

该教师早期职业发展计划（CAREER）赠款将支持研究，这将促进对负荷如何通过土壤转移的基本理解，以及生物机制和新的建筑技术如何改善土壤作为建筑材料的使用。 许多天然材料具有几何微结构，使它们比其基础材料更坚固和更坚韧。 这项研究将提供所需的知识，以便这些机制可以使用增材制造（即3D打印）技术纳入土壤中，其中土壤被“打印”成结构部件或蜂窝图案，以提高其承载能力。 生物启发的结构，如蜂窝已经研究了金属和其他固体材料;然而，缺乏对这些载荷传递机制在颗粒材料如土壤中的有效性的理解。 提高土壤承载能力将通过减少项目所需的混凝土和其他材料的数量来实现更可持续和更具成本效益的岩土工程实践。 在这个项目中获得的基本理解也将使增材制造进一步成为在偏远和欠发达地区以及救灾或饱受战争蹂躏的地区建造庇护所和其他基础设施的可行选择。 此外，该项目旨在通过新课程促进跨学科教育，并通过K-12外展等活动促进不同学生的参与和保留，这些活动侧重于探索自然界中的工程原理，视觉空间研讨会以及通过大学的工程职业意识计划招募高质量的研究人员。分级微结构赋予许多天然材料强度，其强度比其组分大几个数量级。 这项研究的目标是利用这些仿生概念来推进对土壤中负荷转移机制的基本理解。 虽然研究人员已经观察到金属和复合材料的类似生物启发设计的好处，但需要对这些载荷传递机制在土壤等脆性颗粒材料中的有效性有基本的了解。 因此，这项资助的重点是：（1）了解自然界中优化的承载机制，并在土壤中模拟这些机制;（2）使用实验测试和离散元法（DEM）建模来评估生物启发土壤在长度尺度上的行为;以及（3）研究增材制造作为在现场规模上构建细胞土壤织物和基础设施的一种手段。 除了DEM模拟之外，还需要一种基于拓扑的方法来优化给定加载场景的模式并捕获所产生的行为，以便为许多可能的岩土工程应用提供解决方案。 生物改良土壤的实验室和中规模测试也将进行，以评估全面实施该过程的可行性。该奖项反映了NSF的法定使命，并已被认为是值得通过使用基金会的知识价值和更广泛的影响审查标准进行评估的支持。