Chemistry of Alkali-Silica Reaction

碱硅反应化学

• 批准号: 0301485
• 负责人: Leslie Struble
• 金额: $ 12.5万
• 依托单位: University of Illinois at Urbana-Champaign
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2003
• 资助国家: 美国
• 起止时间: 2003-07-15 至 2006-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0301485&HistoricalAwards=false
• 关键词: Chemistry; Alkali; Silica; Reaction

AbstractAlkali-silica reaction (ASR) is a major cause of concrete deterioration. The overall goal of this research project is to combine chemical and mechanical approaches tosubstantially advance fundamental understanding of ASR and to provide a basis for development of more effectiveaccelerated tests and for prevention of damage. The objectives are: 1) to understand the molecular and nanometer-scale structure of ASR gels and how the structure is affected by conditions of formation, 2) to understand themolecular and nanostructural processes that produce the gel, the chemical and structural controls on gelcomposition, and the kinetics of gel formation and subsequent transformations, 3) to understand the effects ofaggregate type on the composition and structure of ASR gel and on the kinetics of gel formation, 4) to understandthe chemical and structural aspects of gel that control swelling behavior, and 5) to understand the relationshipsbetween the macroscopic structural expansion of concrete undergoing ASR and the details of gel formation andswelling by developing a finite element model of concrete expansion that can be used to more effectively predictand evaluate the engineering effects of ASR.The proposed research will have intellectual impact in civil engineering, geological science, andmaterials science. It will provide a detailed understanding of the chemistry of an important concrete deteriorationmechanism, knowledge of the molecular structure of a class of hydrous silicates, ASR gel andestablish a link between molecular structure and swelling behavior. It will establish a microstructural-based modelthat links ASR chemistry and concrete expansion. Knowledge gained through this research will beincorporated into education in both civil engineering and geology. The project will enhance interactions betweenengineering and geology. And the proposed research will enhance minority education through participation Jackson State University, a historically black institution.

碱-硅酸反应(ASR)是混凝土劣化的主要原因。本研究项目的总体目标是将化学和机械方法相结合，实质上促进对ASR的基本了解，并为开发更有效的加速测试和防止损害提供基础。目的是：1)了解ASR凝胶的分子和纳米尺度结构以及形成条件如何影响该结构，2)了解产生凝胶的分子和纳米结构过程，凝胶组成的化学和结构控制，以及凝胶形成和后续转变的动力学，3)了解聚集体类型对ASR凝胶的组成和结构以及凝胶形成动力学的影响，4)了解控制溶胀行为的凝胶的化学和结构方面，5)通过建立混凝土膨胀的有限元模型，更有效地预测和评价ASR的工程效果，了解ASR作用下混凝土宏观结构膨胀与凝胶形成和膨胀细节之间的关系，将对土木工程、地质科学和材料科学产生深远的影响。它将提供对混凝土一种重要的变质机理的化学的详细了解，一类含水硅酸盐的分子结构的知识，ASR凝胶，并在分子结构和膨胀行为之间建立联系。它将建立一个基于微观结构的模型，将ASR化学和混凝土膨胀联系起来。通过这项研究获得的知识将被纳入土木工程和地质学的教育。该项目将加强工程学和地质学之间的互动。这项拟议的研究将通过参与杰克逊州立大学来加强少数民族教育，杰克逊州立大学是一所历史上的黑人机构。