Fig. 1. Geological profile along the Mont Russelin and Mont Terri tunnels (Bossart et al., 2017)
Fig. 2. Mont Terri 'Main Fault' reactivation experiment (after Guglielmi et al., 2014, Guglielmin et al., 2017): (a) SIMFIP test
Fig. 3. Injection pressure scheme
Fig. 4. Field experimental results selected for Task B step 2 modelling: (a) Injection and monitoring pressures and injection flow rate; (b) relative displacement of upper anchor to lower anchor (in vertical, northern and western directions)
Fig. 5. FLAC3D model: (a) rotation of coordinate system for representing in-situ stress condition; (b) numerical mesh in rotated coordinate system
Fig. 6. Initial conditions of normal stress and shear stress acting on fault
Fig. 7. Variations of Injection flow rate obtained from field experiment and numerical model (best matching case)
Fig. 8. Variations of injection pressure and monitoring pressures obtained from field experiment and numerical model (best matching case)
Fig. 9. Variations of Injection flow rate obtained from field experiment and numerical model (best matching case)
Fig. 10. Displacement vector at upper and lower anchors: (a) 420 s and (b) 453 s of water injection (best matching case)
Fig. 11. Fault slip zone and shear displacement in meters simulated at 453 s of injection (best matching case)
Fig. 12. Variations of injection flow rate with different normal stiffness and creation aperture magnitude: (a) kn= 70 GPa, hc=28 μm; (b) Kn= 55 GPa, hc= 40 μm
Fig. 13. Effects of fault dip angle on anchor displacement: (a) dip angle of 60°; (b) dip angle of 70°
Table 1. Parametric study to match field data
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