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.

本研究旨在了解水化硅酸钙（C-S-H）作为水泥水化主要产物的性质及其在水泥基复合材料强度和断裂中的作用。最近墨西哥湾油井的断裂及其相关的环境影响需要彻底了解水泥养护制度的重要性，包括高压和高温对水泥水化产物微观结构的影响，以及这种微观结构对水泥的机械、冲击和抗断裂性的影响。本研究的目的是研究C-S-H合成的基本过程，关联其纳米和微观结构特征，并进一步了解其力学特性，包括蠕变，冲击强度和断裂韧性。范围集中在C-S-H的纳米和微观结构特征是如何改变时，硅酸钙（C/S）的比例改变（比例范围从0.6至1.5），当水化过程发生在不同的温度和压力的组合。通过测试不同固化条件下合成的C-S-H，了解水化条件对C-S-H的硅酸盐聚合和水结构的影响，以及C-S-H纳米结构对其蠕变、断裂和冲击强度的影响。资金将用于支持新墨西哥州大学（UNM）的研究生和本科生：一个少数民族服务机构。这项工作将填补一个主要的知识空白，因为在该领域工作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，并且非常有限的研究提供了关于C-S-H的机械特性的信息。如果成功，我们将揭示一些主要的力学特性，包括蠕变，断裂和冲击强度的C-S-H。成功的研究调查将导致水泥生产的必要变革，以生产耐冲击水泥基复合材料。