Abstract
Tension–shear failure is a typical failure mode in the rock masses in unloading zones induced by excavation or river incision, etc., such as in excavation-disturbed zone of deep underground caverns and superficial rocks of high steep slopes. However, almost all the current shear failure criteria for rock are usually derived on the basis of compression–shear failure. This paper proposes a simple device for use with a servo-controlled compression–shear testing machine to conduct the tension–shear tests of cuboid rock specimens, to test the direct shear behavior of sandstone under different constant normal tensile stress conditions (σ = −1, −1.5, −2, −2.5 and −3 MPa) as well as the uniaxial tension behavior. Generally, the fracture surface roughness decreases and the proportion of comminution areas in fracture surface increases as the change of stress state from tension to tension–shear and to compression–shear. Stepped fracture is a primary fracture pattern in the tension–shear tests. The shear stiffness, shear deformation and normal deformation (except the normal deformation for σ = −1 MPa) decrease during shearing, while the total normal deformation containing the pre-shearing portion increases as the normal tensile stress level (|σ|) goes up. Shear strength is more sensitive to the normal tensile stress than to the normal compressive stress, and the power function failure criterion (or Mohr envelope form of Hoek–Brown criterion) is examined to be the optimal criterion for the tested sandstone in the full region of tested normal stress in this study.
Similar content being viewed by others
References
Aimone-Martin CT, Oravecz KI, Nytra TK (1997) A mechanical device for the measurement of combined shear and tension in rocks. Int J Rock Mech Min Sci 34(1):147–151
Aliha MRM, Ayatollahi MR, Akbardoost J (2012) Typical upper bound–lower bound mixed mode fracture resistance envelopes for rock material. Rock Mech Rock Eng 45(1):65–74
Al-Shayea N (2002) Comparing reservoir and outcrop specimens for mixed mode i–ii fracture toughness of a limestone rock formation at various conditions. Rock Mech Rock Eng 35(4):271–297
Barton N (2013) Shear strength criteria for rock, rock joints, rockfill and rock masses: problems and some solutions. J Rock Mech Geotech Eng 5(4):249–261
Bobich JK (2005) Experimental analysis of the extension to shear fracture transition in Berea Sandstone. MS thesis, Texas A & M University
Bons PD, Elburg MA, Gomez-Rivas E (2012) A review of the formation of tectonic veins and their microstructures. J Struct Geol 43(43):33–62
Brace WF (1964) Brittle fracture of rocks. In: Judd WR (ed) State of stress in the earth’s crust. American Elsevier, New York, pp 111–180
Cho N, Martin CD, Sego DC (2008) Development of a shear zone in brittle rock subjected to direct shear. Int J Rock Mech Min Sci 45(8):1335–1346
Engelder T (1989) Analysis of pinnate joints in the Mount Desert Island granite: implications for postintrusion kinematics in the coastal volcanic belt, Maine. Geology 17(6):564–567
Engelder T (1999) Transitional-tensile fracture propagation: a status report. J Struct Geol 21(8):1049–1055
Ferrill DA, Mcginnis RN, Morris AP, Smart KJ (2012) Hybrid failure: field evidence and influence on fault refraction. J Struct Geol 42:140–150
Fukui K, Okubo S, Ogawa A (2004) Some aspects of loading-rate dependency of Sanjome andesite strengths. Int J Rock Mech Min Sci 41(7):1215–1219
Goodman RE (1989) Introduction to rock mechanics, 2nd edn. Wiley, New York, pp 80–83
Hancock PL (1985) Brittle microtectonics: principles and practice. J Struct Geol 7(3–4):437–457
Hoek E, Brown ET (1980) Empirical strength criterion for rock masses. J Geotech Eng Div 106(9):1013–1035
Hoek E, Martin CD (2014) Fracture initiation and propagation in intact rock—a review. J Rock Mech Geotech Eng 6(4):287–300
Huang RQ, Huang D (2014) Evolution of rock cracks under unloading condition. Rock Mech Rock Eng 47(2):453–466
Huang D, Li Y (2014) Conversion of strain energy in triaxial unloading tests on marble. Int J Rock Mech Min Sci 66(2):160–168
Huang RQ, Wang XN, Chan LS (2001) Triaxial unloading test of rocks and its implication for rock burst. Bull Eng Geol Environ 60(1):37–41
Labuz JF, Zang A (2012) Mohr-Coulomb Failure Criterion. Rock Mech Rock Eng 45(6):975–979
Lin Q, Fakhimi A, Haggerty M, Labuz JF (2009) Initiation of tensile and mixed-mode fracture in sandstone. Int J Rock Mech Min Sci 46(3):489–497
Paterson MS, Wong TF (2005) Experimental rock deformation—the brittle field, 2nd edn. Springer, New York, pp 49–51
Petit JP (1988) Normal stress dependent rupture morphology in direct shear tests on sandstone with applications to some natural fault surface features. Int J Rock Mech Min Sci Geomech Abstr 25(6):411–419
Ramsey JM, Chester FM (2004) Hybrid fracture and the transition from extension fracture to shear fracture. Nature 428(6978):63–66
Reches Z, Lockner D (1994) Nucleation and growth of faults in brittle rocks. J Geophys Res 99(B9):18159–18174
Ren L, Xie LZ, Xie HP, Ai T, He B (2016) Mixed-mode fracture behavior and related surface topography feature of a typical sandstone. Rock Mech Rock Eng. doi:10.1007/s00603-016-0959-3
Rodriguez E (2005) A microstructural study of the extension-to-shear fracture transition in Carrara Marble. MS thesis, Texas A & M University
Saiang D, Malmgren L, Nordlund E (2005) Laboratory tests on shotcrete-rock joints in direct shear, tension and compression. Rock Mech Rock Eng 38(4):275–297
Scott TE, Nielsen KC (1991) The effects of porosity on the brittle-ductile transition in sandstones. J Geophys Res Atmos 96(B1):405–414
Wibberley CAJ, Petit JP, Rives T (2000) Micromechanics of shear rupture and the control of normal stress. J Struct Geol 22(4):411–427
Wu F, Liu T, Liu J, Tang X (2009) Excavation unloading destruction phenomena in rock dam foundations. Bull Eng Geol Environ 68(2):257–262
Xeidakis GS, Samaras IS, Zacharopoulos DA, Papakaliatakis GE (1997) Trajectories of unstably growing cracks in mixed mode i–ii loading of marble beams. Rock Mech Rock Eng 30(1):19–33
Xie HQ, He CH (2004) Study of the unloading characteristics of a rock mass using the triaxial test and damage mechanics. Int J Rock Mech Min Sci 41(Supplement 1):74–80
Acknowledgements
This work is supported by the National Natural Science Foundation of China (Nos. 41472245 and 41672300), the Fundamental Research Funds for the Central Universities (No. 106112016CDJZR208804) and Scientific Research Foundation of State Key Lab. of Coal Mine Disaster Dynamics and Control (No. 2011DA105287-MS201502).
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Cen, D., Huang, D. Direct Shear Tests of Sandstone Under Constant Normal Tensile Stress Condition Using a Simple Auxiliary Device. Rock Mech Rock Eng 50, 1425–1438 (2017). https://doi.org/10.1007/s00603-017-1179-1
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s00603-017-1179-1