ELASTIC STRESS AND STRAIN IN JOINTED ROCK MASSES BY MEANS OF CRACK TENSOR ANALYSIS

Citation
M. Oda et al., ELASTIC STRESS AND STRAIN IN JOINTED ROCK MASSES BY MEANS OF CRACK TENSOR ANALYSIS, Rock mechanics and rock engineering, 26(2), 1993, pp. 89-112
Citations number
18
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Geosciences, Interdisciplinary","Engineering, Civil
ISSN journal
0723-2632
Volume
26
Issue
2
Year of publication
1993
Pages
89 - 112
Database
ISI
SICI code
0723-2632(1993)26:2<89:ESASIJ>2.0.ZU;2-K
Abstract
An elastic stress-strain relation is formulated in terms of crack tens ors which makes it possible to take into account explicitly the effect of joints on elastic behavior of rock masses. The present study is to discuss some related topics which may be encountered in its practical application. Two problems are solved by incorporating the elastic str ess-strain relation into a program for three-dimensional finite elemen t analyses, i. e., stress concentration by surface loading and displac ement by excavation of an intersecting tunnel. Validity of the results is checked by comparing them with a laboratory model test and a field test, with the following conclusions: The overall distribution of str ess definitely depends on a joint stiffness ratio (i.e., normal stiffn ess to shear stiffness). If the ratio is chosen as unity, the stress c oncentration occurs mainly in the direction parallel to major joints. If the ratio is high, sav 10, then the stress concentrates along the p erpendicular as well as the parallel directions to major joints. It ca n be said, on the basis of the fairly good agreement of the calculatio ns using the high stiffness ratio with the field and laboratory measur ements, that the elastic solution by crack tensors provides a practica l tool for estimating the stress and strain in strongly jointed rock m asses.