Synthesis and Multi-Scale Mechanical Characterization of CSH

CSH 的合成和多尺度力学表征

• 批准号: 1131369
• 负责人: Mahmoud Reda Taha
• 金额: $ 19.63万
• 依托单位: University of New Mexico
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-07-15 至 2014-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1131369&HistoricalAwards=false
• 关键词: Synthesis; Multi; Scale; Mechanical; Characterization

This research project aims at understanding the nature of calcium-silicate-hydrate (C-S-H) as the main cement hydration product and its responsibility in the strength and fracture of cement based composites. The recent fracture of oil well in the Gulf of Mexico and its associated environmental impact necessitate a thorough understanding of the significance of cement curing regimes, including high pressure and temperature on the microstructure of cement hydration products and the influence of that microstructure on the mechanical, impact and fracture resistance of cement. The goal of the research is to investigate the fundamental process for synthesis of C-S-H, to correlate its nano and microstructure features, and to further understand its mechanical characteristics including creep, impact strength and fracture toughness. The scope focuses on how the nano and microstructural features of C-S-H are altered when the calcium-silicate (C/S) ratio is changed (ratios ranging from 0.6 to 1.5) and when the hydration process occurs under different combinations of temperatures and pressures. By testing C-S-H synthesized under varying curing conditions, we will understand the significance of hydration conditions on silicate polymerization and water structure of C-S-H and how C-S-H nanostructure affects its creep, fracture and impact strength. Funds will be used to support graduate and undergraduate students in University of New Mexico (UNM): a minority serving institution. This work will fill a major knowledge gap as most researchers working in the field have focused on the chemical and microstructural nature of C-S-H and very limited research has provided information on the mechanical characteristics of C-S-H. If successful, we will reveal some major mechanical characteristics of C-S-H including creep, fracture and impact strength. Successful research investigation shall lead to necessary changes in cement manufacturing to produce impact-tolerant cement-based composites.

该研究项目旨在了解水合硅酸钙（C-S-H）作为主要水泥水化产物的性质及其对水泥基复合材料强度和断裂的影响。最近墨西哥湾油井的破裂及其相关的环境影响需要彻底了解水泥固化方式的重要性，包括高压和高温对水泥水化产物微观结构的影响以及该微观结构对机械、水泥的抗冲击性和抗断裂性。该研究的目标是研究C-S-H合成的基本过程，关联其纳米和微观结构特征，并进一步了解其机械特性，包括蠕变、冲击强度和断裂韧性。该范围重点关注当硅酸钙 (C/S) 比例变化（比例范围从 0.6 到 1.5）以及在不同温度和压力组合下发生水合过程时，C-S-H 的纳米和微观结构特征如何改变。通过测试不同固化条件下合成的C-S-H，我们将了解水合条件对硅酸盐聚合和C-S-H水结构的重要性以及C-S-H纳米结构如何影响其蠕变、断裂和冲击强度。资金将用于支持新墨西哥大学（UNM）的研究生和本科生：少数族裔服务机构。这项工作将填补一个主要的知识空白，因为该领域的大多数研究人员都专注于 C-S-H 的化学和微观结构性质，而提供有关 C-S-H 机械特性的信息的研究非常有限。如果成功，我们将揭示 C-S-H 的一些主要机械特性，包括蠕变、断裂和冲击强度。成功的研究调查将导致水泥制造发生必要的变化，以生产耐冲击的水泥基复合材料。