THERMAL SCIENCE
International Scientific Journal
HYDRAULIC PROPERTIES AND ENERGY DISSIPATION OF DEEP HARD ROCK UNDER H-M COUPLING AND CYCLING LOADS
ABSTRACT
The permeability of deep rock is closely related to the stability and safety of underground engineering. The rocks in deep stratum are mostly with high stress and high osmotic pressure. Therefore, it is necessary to consider the coupling effect between porewater pressure and in situ stress on rock mass. A series of triaxial cyclic loading and unloading experiments under hydraulic-mechanics coupling conditions are carried out to studied the mechanical and hydraulic properties of granite in the depth of 1300 m to 1500 m. Especially, the effect of the disturbance on the permeability of fractured rocks are investigated by unloaded the confining pressure. Tests results presented that the stress-strain curves of deep granite showed typical brittle characteristics. The principal stress of granite exhibited a linear relationship under the high confining pressure of 34-40 MPa and high osmotic pressure of 13-15 MPa. Dissipated energy of the rock decreased to a relatively low level after 2-3 loading cycles and then slowly increased. Permeability showed a decreasing trend as the loading and unloading cycles increase. Finally, acoustic emission technology was used to monitor the fracture evolution in rocks, the acoustic emission signal released as the fractures develop and energy dissipated. The results would provide basic data for the exploitation and excavation in the deep galleries.
KEYWORDS
PAPER SUBMITTED: 2018-07-02
PAPER REVISED: 2018-11-13
PAPER ACCEPTED: 2018-12-24
PUBLISHED ONLINE: 2019-05-12
THERMAL SCIENCE YEAR
2019, VOLUME
23, ISSUE
Supplement 3, PAGES [S935 - S942]
- Qian, Q., et al., Effects of the Axial in Situ Stresses on the Zonal Disintegration Phenomenon in the Surrounding Rock Masses Around a Deep Circular Tunnel, Journal of Mining Science, 48(2012), 2,pp. 276-285
- Zhou, X. P., et al., Excavation-Induced Zonal Disintegration of the Surrounding Rock Around a Deep CircularTunnel Considering Unloading Effect, International Journal of Rock Mechanics and Mining Sciences, 64(2013), pp. 246-257
- Zhou, H., et al., Analysis of Mechanical Behavior of Soft Rocks and Stability Control in Deep Tunnels, Journal of Rock Mechanics and Geotechnical Engineering, 6(2014), 3, pp. 219-226
- Cheng, C., et al., Failure Behavior of Granite Affected by Confinement and Water Pressure and Its Influence on the Seepage Behavior by Laboratory Experiments, Materials, 10(2017), 7
- Ji, S. H., et al., Influence of Pressure Change During Hydraulic Tests on Fracture Aperture,Ground Water,51(2013), 2, pp. 298-304
- Rutqvist, J.,et al., The Role of HydromechanicalCoupling in Fractured Rock Engineering,Hydrogeology Journal, 11(2003), 1, pp. 7-40
- Gao, M. Z., et al., Field Experiments on Fracture Evolution and Correlations Between Connectivity and Abutment Pressure under Top Coal Caving Conditions,International Journal of Rock Mechanics and Mining Science, 111(2018), pp. 84-93
- Brace, W. F., et al., Permeability of Granite Under High Pressure, Journal of Geophysical Research, 73(1968), 6, pp. 2225-2236
- Li, S. P.,et al., Effect of Confining Pressure, Pore Pressure and Specimen Dimension on Permeability of YinzhuangSandstone, International Journal of Rock Mechanics & Mining Science &Geomechanics Abstracts, 34(1997), 3, pp. 432-432
- Wang J. A.,et al., Fluid Permeability of Sedimentary Rocks in a Complete Stress-strain Process, Engineering Geology, 63(2002), 3, pp. 291-300
- Wang H. L., et al., Anisotropic Permeability Evolution Model of Rock in the Process of Deformation and Failure, Journal of Hydrodynamics, 24(2012), 25-31
- Shao, J. F.,et al., Coupling between Anisotropic Damage and Permeability Variation in Brittle Rocks,International Journal for Numerical and Analytical Methods in Geomechanics,29(2005),12, pp. 1231-1247
- Ma, D., et al., Experimental Investigation of Seepage Properties of Fractured Rocks under Different Confining Pressures,Rock Mechanics and Rock Engineering,46(2013), 5, pp. 1135-1144
- Yan, C. L., et al.,Permeability Change Caused by Stress Damage of Gas Shale, Energies, 10(2017), 9
- Meng, Q. B., et al., Effects of Acoustic Emission and Energy Evolution of Rock Specimens under the Uniaxial Cyclic Loading and Unloading Compression,Rock Mechanics and Rock Engineering, 49(2016), 10, pp. 3873-3886
- Li, D., et al., Energy Evolution Characteristics of Hard Rock during TriaxialFailure with Different Loading and Unloading Paths,Engineering Geology, 228(2017), pp. 270-281
- Moradian, Z. A., et al., Evaluating Damage during Shear Tests of Rock Joints Using Acoustic Emissions,International Journal of Rock Mechanics and Mining Sciences, 47(2010),4, pp. 590-598
- Jia, L., et al., Experimental Study and Numerical Modeling of Brittle Fracture of Carbonate Rock under Uniaxial Compression,Mechanics Research Communications, 50(2013), pp. 58-62
- Zhang, R., et al., Fractal Analysis of Acoustic Emission during Uniaxial and TriaxialLoading of Rock, International Journal of Rock Mechanics and Mining Sciences, 79(2015), pp. 241-249
- Heiland, J., Laboratory Testing of Coupled Hydro-mechanical Processes During Rock Deformation, Hydrogeology Journal, 11 (2003), pp.122-141