Collaborative Research: Understanding Fundamental Aspects of the Alkali Silica Reaction through Microwave and Acoustic Measurements

合作研究：通过微波和声学测量了解碱二氧化硅反应的基本方面

• 批准号: 1234151
• 负责人: Reza Zoughi
• 金额: $ 20万
• 依托单位: Missouri University of Science and Technology
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2012
• 资助国家: 美国
• 起止时间: 2012-09-01 至 2015-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1234151&HistoricalAwards=false
• 关键词: Collaborative; Research; Understanding; Fundamental; Aspects

Two new recent insights - the finding that water is tightly held in the alkali-silica gel (ASR) structure, contributing to its expansivity and the proposal that the rate of ASR-induced expansion depends upon the location of the ASR gel formation (i.e., greater expansion when gel forms within the aggregate) - suggest that a renewed and comprehensive examination of ASR is now warranted. The overarching objective of this multi-physics research effort is to bring new understanding to the fundamental aspects of ASR, with specific focus on improving understanding of the relationships between location and volume of ASR gel formation and the composition of the gel, particularly the moisture and calcium contents, on potential for expansion and damage to concrete. This comprehensive effort has been developed to take advantage of the sensitivity of microwave methods to moisture content and binding and the sensitivity of nonlinear and linear acoustic methods to cracking to overcome some of the challenges associated with the in situ examination of durability reactions in cementititious materials. Correlating these data with time-dependent changes in multi-scale structure, composition, and mechanical properties will bring new insight to a reaction which is increasingly damaging to concrete infrastructure.Long-held technical beliefs surrounding ASR in concrete have been increasingly questioned in recent years, undermining the ability of engineers to assess aggregate reactivity, to design ASR-resistant concrete, and to assess the potential for ASR damage in service. New understanding of the progressive ASR damage occurring in concrete will allow for improvements in concrete design to avoid ASR, advances in field monitoring of damage, identification of appropriate maintenance strategies for ASR-damaged structures, and contribute to improved accuracy in service life predictions. Beyond the contributions of improved concrete durability to the broader impact of sustainable development, impact will be made through training and mentoring of a diverse and multi-disciplinary team of graduate and undergraduate researchers at both Georgia Institute of Technology and Missouri University of Science and Technology Broad dissemination of research results to technical and non-technical audiences alike is planned. In addition, the PIs and their students will participate in outreach activities through programs established at their home campuses.

最近的两个新见解——发现水被紧紧地保留在碱硅胶（ASR）结构中，有助于其膨胀性，以及ASR引起的膨胀速率取决于ASR凝胶形成的位置（即，当凝胶在聚集体中形成时膨胀更大）——表明现在有必要对ASR进行更新和全面的检查。这项多物理研究工作的总体目标是为 ASR 的基本方面带来新的认识，特别侧重于提高对 ASR 凝胶形成的位置和体积与凝胶成分（特别是水分和钙含量）之间关系的理解，以及混凝土膨胀和损坏的可能性。这项综合工作的目的是利用微波方法对水分含量和粘合的敏感性以及非线性和线性声学方法对开裂的敏感性，克服与水泥基材料耐久性反应现场检查相关的一些挑战。将这些数据与多尺度结构、成分和机械性能随时间的变化相关联，将为对混凝土基础设施日益损害的反应带来新的见解。近年来，围绕混凝土 ASR 的长期技术信念受到越来越多的质疑，削弱了工程师评估骨料反应性、设计抗 ASR 混凝土以及评估使用中 ASR 损坏潜力的能力。对混凝土中发生的渐进式 ASR 损伤的新认识将有助于改进混凝土设计以避免 ASR、损伤现场监测方面的进步、确定 ASR 损伤结构的适当维护策略，并有助于提高使用寿命预测的准确性。除了提高混凝土耐久性对可持续发展更广泛的影响做出贡献之外，佐治亚理工学院和密苏里科技大学由研究生和本科生研究人员组成的多元化、多学科团队的培训和指导也将产生影响。计划向技术和非技术受众广泛传播研究成果。此外，PI 及其学生将通过在其所在校园设立的项目参与外展活动。

项目成果

Sample Considerations for Short-Circuited Filled Transmission Line Measurements

短路填充传输线测量的示例注意事项

• DOI: 10.1109/i2mtc53148.2023.10175977
• 发表时间: 2023
• 期刊: IEEE
• 作者: Sinkey, Jared;Hook, Alexander;Donnell, Kristen M.
• 通讯作者: Donnell, Kristen M.