A Theoretical Model of Rock Mass Modulus Evaluation
The rock mass is commonly more compliant than the intact rock material due to the presence of fractures. The modulus reduction that results from the presence of fractures is difficult to determine. In situ tests are expensive. Alternatively, a number of correlations are available for extrapolating laboratory-measured quantities to in situ values. For example, use has been made of the correlation between the RQD (rock quality designation) index and the modulus reduction ratio E<,m>/ E -the ratio of the rock mass modulus E<,m> to the laboratory modulus E, determined from small rock samples. This study has developed theoretical model based fracture stiffness. It is assumed that either rock matrix or fractures in a rock mass react elastically under stresses. With this assumption it is possible to evaluate the change in aperture that will occur under a given level of applied strains. In this work, the stress-strain relations for the rock matrix and fractures are developed individually, and deformation compatibility and force balance applied to them to determine the displacement over a fracture. The model agrees with the site data very well.
rock mass modulus hydraulic conductivity fracture FEM
Zhihua Ouyang Mengguo Xu Jianlong Sheng
Wuhan Science and Technology University, China
国际会议
2006现代科技国际研讨会(The International Workshop on Modern Science and Technology in 2006)
北京
英文
217-221
2006-04-01（万方平台首次上网日期，不代表论文的发表时间）