Open AccessStrength of shear bands in fluid-saturated rocks: a nonlinear effect of competition between dilation and fluid flow
Author(s) -
Evgeny V. Shilko,
Andrey V. Dimaki,
S. G. Psakhie
Publication year - 2018
Publication title -
scientific reports
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.24
H-Index - 213
ISSN - 2045-2322
DOI - 10.1038/s41598-018-19843-8
Subject(s) - shear (geology) , dilation (metric space) , nonlinear system , fluid dynamics , flow (mathematics) , mechanics , shear flow , materials science , geology , petrology , geotechnical engineering , chemistry , physics , mathematics , geometry , quantum mechanics
This study shows the significant and nonlinear effect of the competition between dilation and fluid flow on the shear strength of constrained shear bands in fluid-saturated rocks. This effect is conditioned by the contribution of the pore pressure to the yield stress and strength. The pore pressure is controlled by the dilation of the pore space in the solid skeleton of the shear band during plastic deformation and by squeezing of pores in surrounding blocks by the dilating shear band due to the high stiffness of the host massif. A generalized equation has been derived to describe the dependence of the shear band strength on the ratio of strain rate to fluid flow rate.