CAREER: Pickering Stability of Air Bubbles for Superior Air-Entrainment and Frost Durability of Cementitious Materials

事业：气泡的皮克林稳定性可实现水泥材料的卓越引气性和耐冻性

• 批准号: 2340761
• 负责人: Lori Tunstall
• 金额: $ 66.82万
• 依托单位: Colorado School of Mines
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2024
• 资助国家: 美国
• 起止时间: 2024-08-01 至 2029-07-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2340761&HistoricalAwards=false
• 关键词: CAREER; Pickering; Stability; Air; Bubbles

This Faculty Early Career Development (CAREER) award will support research that focuses on solutions for improved concrete sustainability that are urgently needed to combat climate change. While global reductions in CO2 emissions are necessary, CO2 emissions from cement production have increased 1.5% per year from 2015-2021. Two thirds of the global increase in greenhouse gas (GHG) emission in 2019 were attributed to cement production. Improving the durability of new concrete structures is a critical strategy for reducing GHG emissions. Although proper air entrainment is critical for concrete frost durability, conventional air entrainment methods are often ineffective in modern-day mixes. As concrete technology continues to develop at a rapid rate, and as novel alternatives to traditional concrete emerge, a more robust air entrainment solution is needed; one that can overcome known adverse interactions and can be adapted for increasingly complex systems. This work will explore the hypothesis that Pickering stabilization can be used instead of/in addition to current air entrainment approaches for exceptional bubble stability and size control, accelerating adoption of low-carbon building materials without sacrificing their long-term durability and thus sustainability. This research will be integrated into a K-12 education/outreach (EO) program to enrich research, education, and outreach experiences simultaneously. The goal of the EO plan is to develop a diverse, research-literate workforce that can leverage their unique experiences and perspectives to introduce creative, impactful solutions for change. This work will develop the workforce by building a diverse pipeline through a research-integrated K-12 education and outreach program, an undergraduate/graduate training program focused on best practice in inclusive pedagogy and community building, and an annual concrete career week that will introduce grade 8-12 students to hands-on research experience from the work and 5 other concrete career options via facility tours with industry professionals.The project will use molecular dynamic (MD) simulations and experiments to test the hypothesis and develop a fundamental model to describe the mechanisms controlling Pickering stabilization of air bubbles in cementitious systems. The main goal of the research-education activities is to develop a strong integrated program focused on developing air-entrainment solutions via Pickering stabilization, while advancing the STEM workforce in research literacy, diversity, and inclusion. This work will provide a missing, but essential foundation for improving the frost durability of concrete structures, transforming the way the industry entrains air in concrete from trial-and-error empirical practices to systematic, controlled, and predictable air entrainment via exploitation of fundamental principles.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.

该学院早期职业发展（CAREER）奖将支持专注于改善具体可持续性解决方案的研究，这些解决方案是应对气候变化所迫切需要的。虽然全球减少二氧化碳排放量是必要的，但从 2015 年到 2021 年，水泥生产产生的二氧化碳排放量每年增加 1.5%。 2019 年全球温室气体 (GHG) 排放量增长的三分之二归因于水泥生产。提高新型混凝土结构的耐久性是减少温室气体排放的关键策略。尽管适当的加气对于混凝土的抗冻耐久性至关重要，但传统的加气方法在现代混合物中通常无效。随着混凝土技术的持续快速发展，以及传统混凝土的新型替代品的出现，需要更强大的加气解决方案；一种可以克服已知的不利相互作用并且可以适应日益复杂的系统的方法。这项工作将探讨这样的假设：皮克林稳定可以代替/补充当前的加气方法，以实现卓越的气泡稳定性和尺寸控制，从而加速低碳建筑材料的采用，而不牺牲其长期耐用性和可持续性。这项研究将被纳入 K-12 教育/推广 (EO) 计划，以同时丰富研究、教育和推广经验。 EO 计划的目标是培养一支多元化、具有研究素养的员工队伍，他们可以利用他们独特的经验和观点来引入创造性、有影响力的变革解决方案。这项工作将通过研究整合的 K-12 教育和推广计划、专注于包容性教育学和社区建设最佳实践的本科生/研究生培训计划以及每年一次的具体职业周来建立多元化的人才培养渠道，其中将介绍通过与行业专业人士一起参观设施，8-12 年级的学生可以从工作中获得实践研究经验，并获得其他 5 个具体的职业选择。该项目将使用分子动力学 (MD) 模拟和实验来检验假设，并开发一个基本模型来描述控制皮克林的机制水泥体系中气泡的稳定。研究教育活动的主要目标是制定一个强大的综合计划，重点是通过皮克林稳定开发加气解决方案，同时提高 STEM 劳动力的研究素养、多样性和包容性。这项工作将为提高混凝土结构的抗冻耐久性提供一个缺失但重要的基础，通过利用基本原理将行业在混凝土中夹带空气的方式从试错经验实践转变为系统的、受控的和可预测的空气夹带该奖项反映了 NSF 的法定使命，并通过使用基金会的智力价值和更广泛的影响审查标准进行评估，被认为值得支持。