Localization and Size Effect of Failure of Concrete Structures Subjected to Compression

受压混凝土结构破坏的局部化和尺寸效应

基本信息

批准号：
12450176
负责人：
NIWA Junichiro
金额：
$ 6.66万
依托单位：
Tokyo Institute of Technology
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (B)
财政年份：
2000
资助国家：
日本
起止时间：
2000 至 2001
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-12450176/
关键词：
Concrete Localization of Failure Size Effect Compressive Fracture Energy Length of Failure Zone Volume of Failure Zone Deep Beam Shear Failure

项目摘要

When concrete is failed by compression, the failure does not happen throughout the whole body but it concentrates only in some portion of concrete in the post-peak region. By the localization of the failure in compression, the existence of the size effect in structural concrete subjected to compression can be explained.In this study, the uniaxial compression test of concrete in which the cross-sectional shape, the ratio of height and cross section width are parametrically changed has been carried out in order to quantitatively clarify the localization effect. Based on the measured results of local strain, the local energy absorption has been quantitatively evaluated. According to this measurement, it has been clarified that the localization happens for the compression failure of the concrete when the ratio of the height and the cross section width increases to some extent. And, it is found that the localization length (the length of the failure region) can be evaluated using the side l … More ength of the square having the same cross sectional area as the original cross section. In addition, it is found that the absorbed energy per unit volume of failure region (the compression fracture energy) can be evaluated as the function of the compressive strength of concrete. In other words, the compression fracture energy can be considered as the material property. These concepts have been applied to RC deep beams which fail in shear compression failure mode, and it has been confirmed that the concept of the localization can be applied for RC deep beams.The compressive stress-strain relationship which is modified according to the element length to make the energy absorption constant, has been applied for the analysis of RC deep beams in the post-peak region. Then, it has been confirmed that the load-deformation behavior and the size effect of shear strength of RC deep beams can be predicted accurately. The validity has also been confirmed by the comparison with the experimental result.The above results have been summarized and published in Journal of JSCE, Transactions of JCI and also international conference, such as FRAMCOS-4. Less

当混凝土因压缩而失败时，在整个机器人中不会发生故障，它仅集中在PO OST峰区域中的sortion of the of the of the of the of the of the the the po ost po。可以解释压缩。在这项研究中，为基于定位效果而进行了横截面的单轴压缩测试。基于局部应变的结果是，当横截面宽度的比率在某种程度上增加了混凝土的压缩故障。此外，可以将吸收的能量区域（压缩裂缝能量）评估为混凝土的压缩英语。在剪切压缩故障模式下进行RC深色Beail，并且已确认可以应用定位的概念。然后，已经确认了峰值的区域，并且可以准确预测RC深束的剪切强度。在JSCE中，JCI的Tran Sactions和国际会议，例如Framcos-4