Abstract
Joints are an important mechanical feature of rock masses. Their effect on wave propagation is significant in characterizing dynamic behaviors of discontinuous rock masses. An experimental study on wave propagation across artificial rock joint was carried out to reveal the relation between the transmission coefficient and the contact situation of the joint surface. The modified split Hopkinson pressure bar apparatus was used in this study while all the bars and specimens were norite cored from the same site. One surface of the specimens with a number of notches was adopted to simulate the artificial rough joint. Two strain gauges were mounted on each pressure bar at a specific spacing. The incident, reflected and transmitted waves across the joints were obtained using a wave separation method. Comparisons of the transmission coefficients were made under two different conditions: with the same joint thickness but different contact area ratios, and with the same contact area ratio but different joint thicknesses. The results show the effects of contact area ratio and thickness of joints on wave transmission.
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Abbreviations
- \(\varepsilon (t)\) :
-
Strain at time t
- \(\varepsilon_{\text{p}} (t)\), \(\varepsilon_{\text{n}} (t)\) :
-
Positive and negative strains
- \(v(t)\) :
-
Particle velocity at time t
- \(c\) :
-
P wave propagation velocity in the rock bar
- \(\varepsilon_{\text{A}} (t)\), \(\varepsilon_{\text{B}} (t)\) :
-
Test records of the strain gauges A and B
- \(\varepsilon_{\text{Ap}} (t)\), \(\varepsilon_{\text{An}} (t)\), \(\varepsilon_{\text{Bp}} (t)\), \(\varepsilon_{\text{Bn}} (t)\) :
-
Positive and negative strains at the positions of the strain gauges A and B
- \(x_{\text{A}}\), \(x_{\text{B}}\) :
-
Distance between the end surface O and the strain gauge A and B, respectively
- \(\Delta t\) :
-
Time interval for positive or negative strain wave propagation between the positions of the strain gauges A and B
- \(\sigma\) :
-
Stress of the joint
- \(E\) :
-
Young’s modulus of the rock bar
- \(\varepsilon_{\text{I}}\), \(\varepsilon_{\text{T}}\) :
-
Strains in the input and output bars
- \(\varepsilon_{\text{Ip}}\), \(\varepsilon_{\text{In}}\), \(\varepsilon_{\text{Tp}}\), \(\varepsilon_{\text{Tn}}\) :
-
Positive and negative strains of the input and output bars, respectively
- \(\dot{\varepsilon }\) :
-
Strain rate of the joint
- \(L\) :
-
Rock joint thickness
- \(\Delta L\) :
-
Normal closure of the joint
- \(T\) :
-
Transmission coefficient of the joint
- \(\varepsilon_{\text{R}} (t)\) :
-
Strain of the reflected wave caused by the joint
- \(\alpha\), \(\beta\), \(\gamma\), \(\varphi\) :
-
Coefficients of the fitting curves
- B–B:
-
Bandis–Barton
- CT:
-
Computerized tomographic
- ISRM:
-
International Society for Rock Mechanics
- SHPB:
-
Split Hopkinson pressure bar
References
Bandis SC, Lumsden AC, Barton NR (1983) Fundamentals of rock joint deformation. Int J Rock Mech Min Sci Geomech Abstr 20(6):249–268. doi:10.1016/0148-9062(83)90595-8
Benatar A, Rittel D, Yarin AL (2003) Theoretical and experimental analysis of longitudinal wave propagation in cylindrical viscoelastic rods. J Mech Physics Solids 51(8):1413–1431. doi:10.1016/S0022-5096(03)00056-5
Brown ET (1981) Rock characterization, testing and monitoring: ISRM suggested methods. Pergamon Press, Oxford
Brown SR, Scholz CH (1985) Closure of random elastic surfaces in contact. J Geophys Res 90(B7):5531–5545. doi:10.1029/JB090iB07p05531 Solid Earth (1978–2012)
Brown SR, Scholz CH (1986) Closure of rock joints. J Geophys Res 91(B5):4939–4948. doi:10.1029/JB091iB05p04939 Solid Earth (1978–2012)
Chen W, Zhang B, Forrestal MJ (1999) A split Hopkinson bar technique for low-impedance materials. Exp Mech 39(2):81–85. doi:10.1007/BF02331109
Cook NGW (1992) Natural joints in rock: mechanical, hydraulic and seismic behaviour and properties under normal stress. Int J of Rock Mech Min Sci Geomech Abstr 29(3):198–223. doi:10.1016/0148-9062(92)93656-5
Dai F, Xia KW (2013) Laboratory measurements of the rate dependence of the fracture toughness anisotropy of Barre granite. Int J Rock Mech Min Sci 60:57–65. doi:10.1016/j.ijrmms.2012.12.035
Dai F, Huang S, Xia K, Tan Z (2010) Some fundamental issues in dynamic compression and tension tests of rocks using split Hopkinson pressure bar. Rock Mech Rock Eng 43(6):657–666. doi:10.1007/s00603-010-0091-8
Dieterich JH, Kilgore BD (1996) Imaging surface contacts: power law contact distributions and contact stresses in quartz, calcite, glass and acrylic plastic. Tectonophysics 256(1):219–239. doi:10.1016/0040-1951(95)00165-4
Fan LF, Ren F, Ma GW (2012) Experimental study on viscoelastic behavior of sedimentary rock under dynamic loading. Rock Mech Rock Eng 45(3):433–438. doi:10.1007/s00603-011-0197-7
Fardin N, Stephansson O, Jing L (2001) The scale dependence of rock joint surface roughness. Int J Rock Mech Min Sci 38(5):659–669. doi:10.1016/S1365-1609(01)00028-4
Greenwood JA, Williamson JBP (1966) Contact of nominally flat surfaces. Proc R Soc Lond Ser A 295(1442):300–319. doi:10.1098/rspa.1966.0242
Hopkins DL (2000) The implications of joint deformation in analyzing the properties and behavior of fractured rock masses, underground excavations, and faults. Int J Rock Mech Min Sci 37(1):175–202. doi:10.1016/S1365-1609(99)00100-8
Kolsky H (1949) An investigation of the mechanical properties of materials at very high rates of loading. Proc Phys Soc Sect B 62(11):676. doi:10.1088/0370-1301/62/11/302
Li JC, Ma GW (2009) Experimental study of stress wave propagation across a filled rock joint. Int J Rock Mech Min Sci 46(3):471–478. doi:10.1016/j.ijrmms.2008.11.006
Li JC, Li HB, Zhao J (2014) Study on wave propagation across a single rough fracture by the modified thin-layer interface model. J Appl Geophys 110(11):106–114. doi:10.1016/j.jappgeo.2014.09.005
Meng H, Li QM (2003) An SHPB set-up with reduced time-shift and pressure bar length. Int J Impact Eng 28(6):677–696. doi:10.1016/S0734-743X(02)00124-0
Misra A, Marangos O (2011) Rock-joint micromechanics: relationship of roughness to closure and wave propagation. Int J Geomech (special issue: material and computer modeling) 11:431–439. doi: 10.1061/(ASCE (GM. 1943–5622. 0000021)
Pyrak-Nolte LJ, Montemagno CD, Nolte DD (1997) Volumetric imaging of aperture distributions in connected fracture networks. Geophys Res Lett 24(18):2343–2346. doi:10.1029/97GL02057
Wu W, Li JC, Zhao J (2012) Loading rate dependency of dynamic responses of rock joints at low loading rate. Rock Mech Rock Eng 45(3):421–426. doi:10.1007/s00603-011-0212-z
Wu W, Zhu JB, Zhao J (2013) Dynamic response of a rock fracture filled with viscoelastic materials. Eng Geol 160:1–7. doi:10.1016/j.enggeo.2013.03.022
Wu W, Li JC, Zhao J (2014) Role of filling materials in a P-wave interaction with a rock fracture. Eng Geol 172:77–84. doi:10.1016/j.enggeo.2014.01.007
Xia CC, Yue ZQ, Tham LG et al (2003) Quantifying topography and closure deformation of rock joints. Int J Rock Mech Min Sci 40(2):197–220. doi:10.1016/S1365-1609(02)00134-X
Zhao J, Cai JG (2001) Transmission of elastic P-waves across single fractures with a nonlinear normal deformational behavior. Rock Mech Rock Eng 34(1):3–22. doi:10.1007/s006030170023
Zhao H, Gary G (1997) A new method for the separation of waves. Application to the SHPB technique for an unlimited duration of measurement. J Mech Phys Solid 45(7):1185–1202. doi:10.1016/S0022-5096(96)00117-2
Zhao J, Cai JG, Zhao XB et al (2006) Experimental study of ultrasonic wave attenuation across parallel fractures. Geomech Geoeng Int J 1(2):87–103. doi:10.1080/17486020600834613
Acknowledgments
This work was sponsored by the Chinese National Science Research Fund (Grant Nos. 41272348, 51034001) and China Scholarship Council (CSC). The authors also would like to thank Mr. L. Gastaldo and Mr. B. Ferrot of EPFL-LMR for their excellent assistances in specimen preparation, and Professor S. L. Xu of University of Science and Technology of China for his valuable discussions.
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Chen, X., Li, J.C., Cai, M.F. et al. Experimental Study on Wave Propagation Across a Rock Joint with Rough Surface. Rock Mech Rock Eng 48, 2225–2234 (2015). https://doi.org/10.1007/s00603-015-0716-z
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DOI: https://doi.org/10.1007/s00603-015-0716-z