... and irreversible nature of shearing displacements due to the elasto-plastic behavior of rock fractures. For fractures under high normal stress, a residual increase of transmissivity due to dilation is anticipated contrary to the usual expectation of complete transmissivity recovery after unloading...

... of the test. Complete stress-strain curves for the reinforced specimens tended to behave less stiffly in the post-peak state; furthermore, residual strength increased and dilation and the ability of the specimens to withstand residual loading after great straining decreased. The results were extended...

... reservoir geomechanics pillar core strength model Upstream Oil & Gas confinement extensometer data evolution pillar metals & mining Sudbury dilation rock mass Reservoir Characterization stress path constitutive model dilatancy numerical model constitutive model choice...

.... Fifteen tests under CNL and CNS trial procedures were conducted with a servo-controlled direct shear apparatus. The mechanical parameters friction angle and dilatancy were derived from the results of both experimental procedures and compared subsequently. 1 Introduction Rock joints (fractures, faults...

... together of dilation and amplitude of roughness, is introduced by consideration of strength and deformability features. Important details of parameters of this equation are considered. 1 Introduction The energies involved in the geomechanical processes of rock mass discontinuities slidings can...

..., such as in the neighbourhood of faults. Finally there is the wide-reaching problem of stress transformation, from principal stresses to normal and shear stress components on a plane. Dilation, shearing and the very presence of the plane violates the theoretical assumptions. 1 INTRODUCTION 1.1 The importance of rock and rock...

... (amphibolite, gneiss and marble) has been studied based on around 60 compressive uniaxial and triaxial strength tests. The results have been interpreted to obtain peak and residual strength, and post-peak parameters. Particular attention has been given to the study of dilation. The dilation angle...

... of an in-house developed system which is capable of testing large samples up to 100 cm×100 cm under different monotonic and dynamic loading conditions. Upstream Oil & Gas joint surface laboratory apparatus replica normal load dilation asperity high capacity direct shear apparatus Mortar...

... Abstract: The non-linear rock dilation as one of the classic issues has been known for quite a while in rock mechanics community. A better understanding of rock dilation is of considerable importance in order to resolve rock mechanics issues in practical ap-plication. In rock engineering...

... global instability. This rotation creates local dilation; the resistance to dilation by the surrounding rock is equivalent to generation of a force dipole. The latter creates additional tensile stress acting on the plane of future localization zone, which enables rotations of adjacent grains. Thus a zone...

... indicates that the modulus of deformation of the mass is under estimated if dilation of the joints is neglected. The stress-strain behaviour can be reasonably predicted if dilation is taken into account except for the situations where the joints are either perfectly parallel or normal to the loading...

... incorporated in the research program. Work is also progressing on laboratory testing of rock-rock joints. The fundamental laboratory investigations have largely involved the so-called constant normal stiffness (CNS) condition, as the dilation of the concrete-rock pile interface is confined. Dilation...

... the gouge zone. These experiments also reveal a dependence of volumetric strain in the gouge (dilation or compaction) on the rate of shear. If the gouge zone is fluid saturated, dilation or compaction can after the local pore fluid pressure and the effective compressive stress and, hence, the resistance...

... characteristics, loading path, confining pressure, stress tensor relative to jointing and stress-strain-dilatancy is analyzed to characterize this mode of failure in fractured rock masses. Test results from biaxial models and direct shear tests simulating jointed rock masses with an analog material are used...

... parameters (Tse & Cruden, 1979; Reeves, 1985; Yu & Vayssade, 1891) or fractal dimensions (Turk et al., 1987; Lee et al., 1990; Xie & Pariseau, 1992) of the B-C profiles. machine learning strength normal stress coefficient Upstream Oil & Gas Barton dilation aluminum specimen...