Characterization of the crystal structure, kinematics, stresses and rotations in angular granular quartz during compaction.
Characterization of the crystal structure, kinematics, stresses and rotations in angular granular quartz during compaction.
复制标题
压实过程中角颗粒石英中晶体结构，运动学，应力和旋转的表征。
DOI：
10.1107/s1600576718006957
复制
发表时间：
2018-08-01
影响因子：
6.1
通讯作者：
Pagan DC
中科院分区：
文献类型：
--
作者：
Hurley RC;Herbold EB;Pagan DC
三维X射线衍射和X射线计算机断层扫描被用来研究颗粒尺度的角粒状材料的响应，以了解压实过程中的颗粒运动学，应力和旋转，并比较角颗粒与球形颗粒的响应。三维X射线衍射（3DXRD）是一种用于量化大单晶集合体的位置、取向和弹性应变的方法，最近已成为研究压实过程中颗粒材料的机械响应的重要工具。应用已经证明了3DXRD和X射线计算机断层扫描（XRCT）用于评估应变、颗粒应力和取向、颗粒间接触和力、颗粒断裂力学和原位孔隙度演变的实用性。虽然过去的研究采用3DXRD和XRCT已经阐明了球形颗粒填料和角形颗粒填料与少量的颗粒的力学，一直是有限的努力，迄今为止，在研究角形颗粒填料与大量的颗粒，并在比较这些填料的力学与那些由大量的球形颗粒。因此，本论文的重点是在压实过程中使用原位3DXRD的角度石英颗粒的晶体结构，运动学，应力和旋转的几百个角颗粒的力学研究。角晶粒和球形晶粒的压实响应之间的比较，并在单个晶粒内的应力诱导孪生进行了讨论。
Three-dimensional X-ray diffraction and X-ray computed tomography are used to study the grain-scale response of angular granular materials to understand grain kinematics, stresses and rotations during compaction and to compare the responses of angular grains with those of spherical grains. Three-dimensional X-ray diffraction (3DXRD), a method for quantifying the position, orientation and elastic strain of large ensembles of single crystals, has recently emerged as an important tool for studying the mechanical response of granular materials during compaction. Applications have demonstrated the utility of 3DXRD and X-ray computed tomography (XRCT) for assessing strains, particle stresses and orientations, inter-particle contacts and forces, particle fracture mechanics, and porosity evolution in situ. Although past studies employing 3DXRD and XRCT have elucidated the mechanics of spherical particle packings and angular particle packings with a small number of particles, there has been limited effort to date in studying angular particle packings with a large number of particles and in comparing the mechanics of these packings with those composed of a large number of spherical particles. Therefore, the focus of the present paper is on the mechanics of several hundred angular particles during compaction using in situ 3DXRD to study the crystal structure, kinematics, stresses and rotations of angular quartz grains. Comparisons are also made between the compaction response of angular grains and that of spherical grains, and stress-induced twinning within individual grains is discussed.