Preserving microstructure of concrete under load using the Wood’s metal technique
Preserving microstructure of concrete under load using the Wood’s metal technique
复制标题
使用伍德金属技术保持荷载下混凝土的微观结构
DOI：
10.1016/s1365-1609(99)00099-4
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发表时间：
2000
期刊：
影响因子：
--
通讯作者：
K. Nemati
中科院分区：
文献类型：
--
作者：
K. Nemati
开发了一种特殊的实验技术，使混凝土中的微观结构和压应力引起的微裂纹在施加载荷下存在时得以保存。对混凝土圆柱试件进行了单轴和三轴压缩试验。由此产生的诱导裂纹用金属合金（Wood's metal）浸渍，该金属合金在较高温度（70-85°C）下液化，但在常温下是固体。在感兴趣的应力下，该合金被固化以保持应力诱导的微裂纹，因为它们在负载下存在。采用扫描电子显微镜（SEM）从混凝土试样的横截面捕获图像。体视学提供了将三维结构与其二维截面相关联的几何统计背景。体视学估计得到的总裂纹扩展每单位体积。在此基础上，分析了裂纹在截面上的二维特征，如裂纹的取向分布、长度等。
A special experimental technique was developed which made possible the preservation of microstructure and the compressive stress-induced microcracks in concrete as they exist under applied loads. Cylindrical specimens of concrete were tested under uniaxial and triaxial compression. The resulting induced cracks were impregnated with a metal alloy, Wood’s metal, that liquefies at higher temperatures (70–85°C), but is solid at normal temperatures. At the stress of interest, this alloy was solidified to preserve the stress-induced microcracks as they exist under load. Scanning Electron Microscopy (SEM) was employed to capture images from the cross sections of the concrete specimens. Stereology presents the geometrical statistical background for relating three-dimensional structures to their two-dimensional sections. Stereological estimates were obtained for total crack extension per unit of volume. Further, two-dimensional features of the cracks were analyzed in the section plane, such as orientation distribution, and length.