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

本研究的目的是调查的形成和程度， 混凝土断裂过程区微裂纹的激光散斑研究 计量学 具体来说，这项研究将检测密集的 在工艺区内填充微裂纹区域，测量 微裂纹宽度的增加，描述宏观裂纹-微裂纹 从实验演变，并开发一个模型来评估裂纹 混凝土中的生长和断裂参数。 这些研究报告将 对波特兰水泥、砂浆和混凝土试样进行了试验。 两 双悬臂梁试件和仿形双悬臂梁 梁试样将被检查。 一系列的标本将被测试 两侧有凹槽。 另外两个系列的标本将 测试：一个系列将只在一侧有凹槽，另一个系列将只在一侧有凹槽， 系列将完全没有凹槽。 三个主要系列包括 不同的材料、试样类型和试样尺寸。

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.