The Effect of Cement Milk Grouting on the Deformation Behavior of Artifcial Rock Joints

시멘트현탁액 주입에 의한 신선한 암석절리의 역학적 특성 변화

  • 김태혁 (대본엔지니어링 터널팀) ;
  • 이정인 (서울대학교 지구환경시스템공학부)
  • Published : 2000.06.01

Abstract

Grouting has been practiced as a reliable technique to improve the mechanical properties of rock mass. But, the study of ground improvement by greeting is rare especially in jointed rock mass. In this study, joint compression test and direct shear test were performed on pure rock joint and cement milk grouted rock joint to examine the grouting effect on the property of rock joint. In the pure rock joint compression test, joint closure varied non-linearly with normal stress. But after cement milk grouting, the normal deformation characteristics of the joint was linear at the low normal stress level. As normal stress increased. deformation of the sample rapidly increased due to the stress concentration at the joint asperities. Peak shear strength of the grouted joint in low normal stress was higher than that of non-grouted joint due to the cohesion, decreased exponetially as the grout thickness increased. Thus after cement milk grouting, the failure envelope modified to a curve that has cohesion due to grout material hydration with decreased friction angle. Shear stiffness and peak dilation angle of the grouted joint decreased as the grout thickness increased. The peak shear strength from the direct shear test on grouted rock joint was represented by an empirical equation as a fuction of grout thickness and roughness mean amplitude.

References

  1. 대한토목학회논문집 v.10 no.3 신선한 화강암 절리면에서 약액에 의한 전단강도의 변화에 대한 연구 정형식;이승호
  2. Proc.of the Int.Conf.on Rock Joints Mechanical Properties of Rock Joint Bandis S.C.
  3. Int. J. Rock Mech. Min. Sci & Geomech. Abstr. v.30 no.2 The Effect of Frictional Fill Thickness on the Shear Strength of Rock Discontinuities Papaliangas T.;Hencher S.R.;Lumsden A.C.;Manolopoulou S.
  4. Proc.on Mechanics of jointed and faulted rock Mechanical Properties of Strengthened Rock Joint Szwedzicki T.
  5. Proc.of the Int. Conf.on Rock Joint Effect of Infill Thickness on Shear Behavior of Rock Joints Phien-wei N.;Shrestha U.B.;Rantucci G.
  6. Proc.of 6th Int.Cong.on Rock Mechanics, Montreal v.1 New Development in Seam Treatment of Feitsui Arch Dam Foundation Cheng Y.
  7. Rock Mech. v.10 The Shear Strength of Rock Joints in Theory and Practice Braton N.;Choubey V.
  8. ASTM Journal v.8 no.4 Evaluation of Adhesion in Chemically Grouted Geomaterials Raymond J.Kriezek;Cumaraswamy Vipulanandan
  9. 폐광지역 지반침하 메커니즘 및 침하방지 공법에 관한 연구
  10. Proc.on Rock Joints Shear Behaviour of Cement Grout Filled Artificially Created Planer Joint Srivastava R.K.;Jalota A.V.;Amir A.A.A.
  11. 지반개량을 위한 그라우팅공법에 관한 연구
  12. Rock Characterization Testing and Monitoring Suggested Methods for the Quantitative Description of Discontinuites in Rock Mass
  13. Int.J.Rock Mech.Min.Sci.& Geomech. Abstr. v.34 no.174 Characterization of Joint Profiles and Their Roughness Parameters Lee, S.D.;Lee, C.I.;Park, Y.
  14. Proc.of 8th Int.Cong.on Rock Mechanics Experimental Quantification of the Stabilizing Effect of Polyurethane and Silicate Resins Natau, O.;Mutschler Th;Stech,H.J.