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混凝土可持续性解决方案的研究，这些解决方案是应对气候变化迫切需要的。虽然减少全球二氧化碳排放是必要的，但从2015年到2021年，水泥生产的二氧化碳排放量每年增长1.5%。2019年全球温室气体（GHG）排放增量的三分之二归因于水泥生产。提高新混凝土结构的耐久性是减少温室气体排放的关键策略。虽然适当的空气夹带是关键的混凝土霜冻耐久性，传统的空气夹带方法往往是无效的现代混合。随着混凝土技术的快速发展，以及传统混凝土的新替代品的出现，需要一种更强大的空气夹带解决方案；一个可以克服已知的不利相互作用，并可以适应日益复杂的系统。这项工作将探索一种假设，即皮克林稳定可以用来代替/除了目前的空气夹带方法，以实现卓越的气泡稳定性和尺寸控制，加速采用低碳建筑材料，而不会牺牲其长期耐用性和可持续性。这项研究将整合到K-12教育/外展（EO）计划中，以同时丰富研究、教育和外展经验。EO计划的目标是培养一支多元化的、具有研究素养的员工队伍，这些员工能够利用他们独特的经验和观点，为变革引入创造性的、有影响力的解决方案。这项工作将通过建立一个多元化的管道来发展劳动力，通过一个综合研究的K-12教育和推广计划，一个本科生/研究生培训计划，专注于包容性教学法和社区建设的最佳实践，以及一个年度具体职业周，向8-12年级的学生介绍从工作中获得的实践研究经验，以及通过与行业专业人士一起参观设施，其他5个具体的职业选择。该项目将使用分子动力学（MD）模拟和实验来验证这一假设，并建立一个基本模型来描述胶凝系统中气泡皮克林稳定化的控制机制。研究教育活动的主要目标是制定一个强大的综合计划，专注于通过皮克林稳定化开发空气夹带解决方案，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性提供一个缺失的、但必不可少的基础，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、可控的和可预测的夹带空气的方式。该奖项反映了美国国家科学基金会的法定使命，并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，被认为值得支持。