DOI QR코드

DOI QR Code

Microplane Constitutive Model for Granite and Analysis of Its Behavior

마이크로플레인 모델을 이용한 화강암의 3차원 구성방정식 개발 및 암석거동 모사

  • 지광습 (고려대학교 공과대학 사회환경시스템공학과) ;
  • 문상모 (고려대학교 사회환경시스템공학과) ;
  • 이인모 (고려대학교 공과대학 사회환경시스템공학과)
  • Published : 2006.02.01

Abstract

The brittle materials like rocks show complicated strain-softening behavior after the peak which is hard to model using the classical constitutive models based on the relation between strain and stress tensors. A kinematically constrained three-dimensional microplane constitutive model is developed for granite. The model is verified by fitting the experimented data of Westerly granite and Bonnet granite. The triaxial behavior of granite is well reproduced by the model as well as the uniaxial behavior. We studied the development of the fracture zone in granite during blasting impact using the model with the standard finite element method. All the results obtained from the microplane model developed are compared to those from the linear elasticity model which is commonly used in many researches and practices. It is found that the nonlinearity of rocks sigificantly affects the results of analysis.

텐서(tensor) 이론에 기초한 기존의 구성방정식 모델은 암석(rock)과 같은 준취성 재료에서 나타나는 복잡한 변형열화(strain softening) 과정을 기술하기가 어려우며, 특히 구속압에 따른 변형열화 과정의 변화를 잘 반영하지 못한다. 본 연구에서는 화강암의 3차원 거동을 예측 분석할 수 있는 구성방정식을 마이크로플레인 모델을 이용하여 개발하였다. 화강암에 대한 마이크로플레인 모델은 Westerly 화강암과 Bonnet 화강암의 일축압축 및 삼축압축 시험 데이터와 최적을 이루도록 개발되었다. 개발된 마이크로플레인 모델은 화강암의 일축 및 삼축거동을 잘 예측하였다. 그리고 개발된 화강암의 마이크로플레인 모델을 유한요소법에 적용하여 암석지반 굴착시의 발파 모사를 통해 화강암의 비선형 거동 및 발파시의 파쇄 영역을 해석하였다. 또한 마이크로플레인 모델을 이용한 비선형 해석결과와 탄성해석 결과를 비교 분석한 결과 화강암의 거동은 비선형에 크게 영향을 받는 것으로 나타났다.

Keywords

References

  1. 박봉기 (2004), 터널 발파굴착에서 발파응력과 암반손상의 확률론적 연구, 공학박사학위논문, 고려대학교
  2. 최용근, 배성호, 박배한, 이정인, 전석원 (2001), '파괴역학모델을 이용한 수압파쇄시험 결과의 해석에 관한 연구', 터널과 지하공간, 한국암반공학회지, 제 11권, 제 3호, pp.237-247
  3. Bazant, Z.P. (1984), 'Chapter 3: Microplane model for strain controlled inelastic behavior.', Proc. Mech.. of Engrg. Mat., C. S. Desai and R. H. Gallagher eds., Wiley London, pp.45-59
  4. Bazant, Z.P. and Prat, P.C. (1988), 'Microplane model for brittle plastic material: I. Theory', Journal of Engineering Mechanics, ASCE, Vol.114, pp.1672-1688 https://doi.org/10.1061/(ASCE)0733-9399(1988)114:10(1672)
  5. Bazant, Z.P. and Prat, P.C. (1988), 'Microplane model for brittle plastic material: II. Verification', Journal of Engineering Mechanics, ASCE, Vol.114, pp.1689-1702 https://doi.org/10.1061/(ASCE)0733-9399(1988)114:10(1689)
  6. Bazant, Z.P. and Oh, B.H. (1985), 'Microplane model for progressive fracture of concrete and rock', Journal of Engineering Mechanics, ASCE, Vol.111, pp.559-582 https://doi.org/10.1061/(ASCE)0733-9399(1985)111:4(559)
  7. Bazant, Z.P., Xiang, Y. and Prat, P.C. (1996), 'Microplane model for concrete. I. Stress-strain 6.boundaries and finite strain', Journal of Engineering Mechanics, ASCE, Vol.122, No.3, pp.245-254 (with Errata Vol.123, No.3, pp.411) https://doi.org/10.1061/(ASCE)0733-9399(1996)122:3(245)
  8. Bazant, Z.P., Xiang, Y., Adley, M.D., Prat, P.C. and Akers S.A. (1996), 'Microplane Model for Concrete II: Data Delocalization and Verification', Journal of Engineering Mechanics, ASCE, Vol.122, No.3, pp.255-262 https://doi.org/10.1061/(ASCE)0733-9399(1996)122:3(255)
  9. Bazant, Z.P. And Cedolin, L. (1991), Stability of Structures: Elastic, Inelastic, Fracture, and Damage Theories, Oxford University Press, New York
  10. Bazant, Z.P., Caner, F.C., Adley, M.D. and Akers, S.A. (2000), 'Microplane model M4 for concrete I: formulation with workconjugate deviatoric stress', Journal of Engineering Mechanics, ASCE, Vol.126, No.9, pp.944-953 https://doi.org/10.1061/(ASCE)0733-9399(2000)126:9(944)
  11. Bazant, Z.P. and Zi, G. (2003), 'Microplane constitutive model for porous isotropic rocks', International Journal for Numerical an Analytical Methods in Geomechanics, Vol.27, pp.25-47 https://doi.org/10.1002/nag.261
  12. Brace, W.F., Paulding, B. and Scholz, C. (1966), 'Dilatancy in the fracture of crystalline rocks', Journal of Geophysical Research, Vol.71, pp.3939-3953 https://doi.org/10.1029/JZ071i016p03939
  13. Brace, W.F. and Riley, D.K. (1972), 'Static uniaxial deformation of 15 rocks to 30kb', International Journal of Rock Mechanics and Mining Sciences, Vol.9, pp.271-288 https://doi.org/10.1016/0148-9062(72)90028-9
  14. Caner, F.C. and Bazant, Z.P. (2000), 'Microplane Model M4 for Concrete II: algorithm and calibration', Journal of Engineering Mechanics, ASCE, Vol.126, No.9, pp.954-961 https://doi.org/10.1061/(ASCE)0733-9399(2000)126:9(954)
  15. Carol, I., Bazant, Z.P. and Prat, P.C. (1991), 'Geometric damage tensor based on microplane model', Journal of Engineering Mechanics, Vol.117, No.10, pp.2429-2448 https://doi.org/10.1061/(ASCE)0733-9399(1991)117:10(2429)
  16. Fujii, Y., Kiyama, T., Ishijima, Y. and Kodama, J. (1998), 'Examination of a Rock Failure Criterion Based on Circumferential Tensile Strain', Pure and Applied Geophysics, Vol.152, pp.551-577 https://doi.org/10.1007/s000240050167
  17. Hoxha, D. and Homand, F. (2000), 'Microstructural approach in damage modeling', Mechanics of Materials, Vol.32, pp.377-387 https://doi.org/10.1016/S0167-6636(00)00006-5
  18. Jirasek, M. (1993), 'Modeling of fracture and damage in quasibrittle materials', Ph. D. Dissertation, Northwestern University: Evanston, IL
  19. Martin, C.D. and Chandler, N.A. (1994), 'The progressive fracture of Lac du Bonnet granite', International Journal of Rock Mechanics and Mining Sciences and Geomechanics Abstracts, Vol.31, No.6, pp.643-659 https://doi.org/10.1016/0148-9062(94)90005-1
  20. Martin, C.D. (1997), 'Seventeenth Canadian Geotechnical Colloquium: The effect of cohesion loss and stress path on brittle rock strength', Canadian Geotechnical Journal., Vol.34, pp.698-725 https://doi.org/10.1139/cgj-34-5-698
  21. Mastuda, Koji., Mizutani, Hitoshi., and Yamada, Isao (1987), 'Experimental Study of Strain-rate dependence and Dependence of Failure Properties of granite', Journal of physics of the earth, Vol.35, pp.37-66 https://doi.org/10.4294/jpe1952.35.37
  22. Peng, S. A. and Johnson, M. (1972), 'Crack growth and faulting in cylindrical specimens of Chelmsford granite', International Journal of Rock Mechanics and Mining Sciences, Vol.9, pp.37-86 https://doi.org/10.1016/0148-9062(72)90050-2
  23. Taylor, G.I. (1938), 'Plastic strain in metals', The Journal of the Institute of Metals, Vol.62, pp.307-324
  24. Tapponier, P. and Brace, W.F. (1976), 'Development of stressinduced microcracks in Westerly granite', International Journal of Rock Mechanics and Mining Sciences and Geomchanics Abstracts, Vol.13, pp.103-112 https://doi.org/10.1016/0148-9062(76)91937-9
  25. Valliappan, s. and Wang, Y. C. (1994), 'Advances in Computational Mechanics Applied to Wave Propagation Problem', Computer Methods and Advances in Geomechanics, pp.347-360
  26. Wawersik, W.R. and Brace, W.F. (1971), 'Post-failure behavior of a granite and diabase', Rock Mechanics, Vol.3, pp.61-85 https://doi.org/10.1007/BF01239627