著者

金子 賢治 岸野 佑次

出版者

Japan Society of Civil Engineers

雑誌

応用力学論文集 (ISSN:13459139)

巻号頁・発行日

vol.4, pp.385-396, 2001-08-29 (Released:2010-03-17)

参考文献数

23

---

Observing numerical results obtained by Granular Element Method, we discuss the incremental stress-strain behavior of granular materials. We assume a periodic boundary for the numerical experiments to avoid disturbances caused by boundary controlling. Stress-probe tests starting with the intermediate data of a bi-axial compression test give a set of incremental stress-strain relationships. The result indicates that the flow direction for plastic loading is not constant as is assumed in the classical plasticity theory and depends on the direction of the stress increment. Comparing the numerical results with a proposed flow rule, we conclude that the origin of the direction dependency is the volumetric component of plastic strain.

著者

武 建勲 岸野 佑次 浅沼 秀雄

出版者

Japan Society of Civil Engineers

雑誌

応用力学論文集 (ISSN:13459139)

巻号頁・発行日

vol.1, pp.497-506, 1998-08-26 (Released:2010-03-17)

参考文献数

9

---

The authors have performed a set of numerical loading tests in terms of the Granular Element Method. The tests exhibit mechanical behaviors which are common among real behaviors of geological materials. These test results are very suggestive to know the internal mechanism hidden behind the macroscopic behaviors. This paper mainly concerns the plastic behavior whose mechanism has its main origin on the slipping between grains. A theoretical yielding condition, which explains the result obtained by the simulation, is derived from non-slipping condition for stable assemblies of rigid particles. Performing eigen-value analyses of the instantaneous stiffness matrix which is utilized in the Granular Element Method, the authors demonstrate the similarity of displacement fields accompanied by plastic deformations for different loading directions. This similarity explains why the common direction of plastic strain is assumed in the flow rule.