A constitutive model for shear induced anisotropic degradation of weak sandstone
Journal
ISRM International Symposium on Rock Mechanics, SINOROCK 2009
Date Issued
2009
Author(s)
Abstract
Weak sandstones possess deformational behaviors different from hard rocks; these phenomena, including shear dilation and degradation of deformational moduli, are much more significant. Therefore, a model capable of simulating major deformational characteristics of weak sandstones is essentially needed for engineering purposes. An innovative constitutive model is accordingly proposed. The proposed model was formulated based on the linear elastic model, and it accounts for the variations of moduli K and G through different loading conditions. In addition, an anisotropic factor β is introduced to reflect the stress-induced anisotropy. It was found that the proposed model is able to closely simulate the actual deformational characteristics of weak sandstones. The proposed model was then incorporated into a finite element program and was used to analyze a squeezing tunnel case. Overall, this model can describe the deformation behavior for weak sandstones, especially on the significant shear dilation prior to the failure state. As a result, the proposed model shows the versatility in its applicability. © ISRM International Symposium on Rock Mechanics, SINOROCK 2009.
Event(s)
ISRM International Symposium on Rock Mechanics 2009, SINOROCK 2009
Publisher
International Society for Rock Mechanics
Description
ISRM International Symposium on Rock Mechanics 2009, SINOROCK 2009, 19 May 2009 through 22 May 2009, Hong Kong
Type
conference paper