Use of Stereophotogrammetry to Analyze the Development of Shear Bands in Sand
Use of Stereophotogrammetry to Analyze the Development of Shear Bands in Sand
复制标题
DOI：
10.1520/gtj11016j
复制
发表时间：
1995-12
影响因子：
1.6
通讯作者：
W. W. Harris-W.;G. Viggiani;M. Mooney;R. Finno
中科院分区：
文献类型：
--
作者：
W. W. Harris-W.;G. Viggiani;M. Mooney;R. Finno
给出了一种细粒饱水松砂的平面应变压缩实验结果。结合边界应力和变形的局部测量，通过对变形试件照片的系统分析，可以测量变形并计算剪切带内外的应变场。描述了该方法的原理、细节和准确性。通过不排水和排水试验获得的典型结果，说明了立体摄影测量的能力。系统地观察到了从均匀变形到局部应变的临时模式到高度局域应变场的逐渐转变。在最终形成剪切带的区域应变局部化之前，土体比试件的其余部分收缩得更大。一旦最终带完全形成，带内的土壤要么保持恒定体积，要么膨胀。在整体不排水的情况下，整个样品的体积响应不均匀，这意味着样品内有水流动。
Experimental results are presented from plane-strain compression of a fine-grained, water-saturated loose sand. Together with local measurements of boundary stresses and deformations, systematic analysis of photographs of the deforming specimen allowed for measuring deformations and computing strain fields inside and outside the shear band. The principles, details, and accuracy of the procedure are described. The capabilities of stereophotogrammetry are illustrated through typical results obtained from undrained and drained tests. A gradual transition from homogeneous deformation to temporary modes of localized strain to a highly localized strain field is systematically observed. Prior to strain localization in the region where the final shear band eventually forms, the soil contracts more than the rest of the specimen. As soon as the final band is fully formed, the soil inside the band either remains at constant volume or dilates. The nonuniformity of volumetric response throughout the specimen in globally undrained conditions implies there is water flow within the specimen.