Research Initiation: Determination of Microcracked Zone in Concrete by Laser Speckle Metrology

研究启动：利用激光散斑计量法测定混凝土中的微裂纹区域

• 批准号: 8505273
• 负责人: Farhad Ansari
• 金额: --
• 依托单位: New Jersey Institute of Technology
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 1985
• 资助国家: 美国
• 起止时间: 1985-09-01 至 1988-02-28
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=8505273&HistoricalAwards=false
• 关键词: Research; Initiation; Determination; Microcracked; Zone

Objectives of this study are to investigate the formation and extent of microcracks in fracture process zone of concrete by laser speckle metrology. Specifically, the research will detect the densely populated microcracked region within the process zone, measure the rate of increase in microcrack width, describe the macrocrack-microcrack evolution from experiments, and develop a model to evaluate the crack growth and fracture parameters in concrete. These studies will be carried out for portland cement, mortar, and concrete specimens. Both double cantilever beam specimen and the contoured double cantilever beam specimen will be examined. A series of specimens will be tested with grooves on both sides. Two other series of specimens will be tested: one series will have grooves only on one side, and the other series will have no grooves at all. The three major series comprise different materials, specimen type, and specimen dimensions.

利用激光散斑测量技术研究混凝土断裂过程区微裂纹的形成和程度。具体而言，研究将检测工艺区内密集的微裂纹区域，测量微裂纹宽度的增加速率，从实验中描述宏观裂纹-微裂纹的演变，并建立一个模型来评估混凝土中的裂纹扩展和断裂参数。这些研究将在波特兰水泥、砂浆和混凝土样品中进行。双悬臂梁试件和异形双悬臂梁试件都将进行检测。一系列的样品将在两侧进行凹槽测试。另外两个系列的试样将进行测试：一个系列只在一侧有沟槽，另一个系列根本没有沟槽。这三个主要系列包括不同的材料、试样类型和试样尺寸。