MODELING OF SUBSIDENCE AND STRESS-DEPENDENT HYDRAULIC CONDUCTIVITY FOR INTACT AND FRACTURED POROUS-MEDIA

Authors
Citation
M. Bai et D. Elsworth, MODELING OF SUBSIDENCE AND STRESS-DEPENDENT HYDRAULIC CONDUCTIVITY FOR INTACT AND FRACTURED POROUS-MEDIA, Rock mechanics and rock engineering, 27(4), 1994, pp. 209-234
Citations number
33
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Geosciences, Interdisciplinary","Engineering, Civil
ISSN journal
0723-2632
Volume
27
Issue
4
Year of publication
1994
Pages
209 - 234
Database
ISI
SICI code
0723-2632(1994)27:4<209:MOSASH>2.0.ZU;2-Z
Abstract
This study investigates the changes in deformation and stress dependen t hydraulic conductivities that occur as a result of underground minin g in intact and fractured porous media. The intact porous medium is as sumed to be comprised of regularly packed spherical grains of uniform size. The variation in grain size or pore space due to the effect of c hanging intergranular stresses results in a change in rock hydraulic c onductivity. A model is developed to describe the sensitivity of hydra ulic conductivity to effective stresses through Hertzian contact of sp herical grains. The fractured porous medium is approximated as an equi valent fracture network in which a single fracture is idealized as a p lanar opening having a constant equivalent thickness or aperture. Chan ges in fracture aperture as a result of changes in elastic deformation control the variation of hydraulic conductivity. A model is presented to illustrate the coupling between strain and hydraulic conductivity. Subsidence induced deformations that result from mining induced chang es in hydraulic conductivity in both intact and fractured media. These changes are examined and compared with results from a mining case stu dy.