Acta Geotechnica - A 3D multi-scale approach is presented to investigate the mechanical behavior of a macroscopic specimen consisting of a granular assembly, as a boundary value problem. The core... 相似文献
Triaxial test has been widely used to investigate the stress–strain relationship of unsaturated soils. During triaxial testing, soil volume is an essential parameter to be measured. For an unsaturated soil, due to the presence of air phase, accurate volume/deformation measurement during triaxial testing was a great challenge for researchers. Recently, a photogrammetry-based method has been developed to measure the soil volume/deformation during triaxial testing. Preliminary triaxial test results indicate the new method is simple, accurate, and cost- and time-effective. However, some concerns regarding its measurement accuracy and applicability, which are critical for the dissemination of the photogrammetry-based method, have been raised by other researchers. These concerns were addressed in details in this study. The factors concerning the deformation measurement accuracy were systematically evaluated through a series of triaxial tests on an aluminum cylinder with different confining media and chamber pressures. A sensitivity analysis was carried out to investigate the impact of the system parameters on the volume measurement accuracy of the photogrammetry-based method. In addition, a triaxial test on a saturated sand specimen was conducted to evaluate the influences of mesh density, mesh pattern, and interpolation technique on the volume change measurement accuracy. Finally, some suggestions were provided to improve the accuracy of the photogrammetry-based measurement method.
In this study, a directional interpolation infinite element suited to a saturated porous medium is presented to account for dynamic problems with semi-infi 相似文献
1.Current status Three-dimensional(3D)inversion of geophysical EM data is generally underdetermined,non-linear,and of large-scale that is very difficult to solve by optimization.In the past two decades,with the advancement of computational equipment and numerical algorithms,3D geophysical EM inversion has made great progress.Numerous inversion codes and platforms based on the regularizations have been successfully developed and are being widely used in the industry and scientific research.The development of 3D EM inversions mainly involve the following aspects. 相似文献