Simulation of Cracking Behavior Induced by Drying Shrinkage in Fiber Reinforced Concrete Using Irregular Lattice Model

무작위 격자 모델을 이용한 파이버 보강 콘크리트의 건조수축 균열 거동 해석

  • 김근휘 (연세대학교 대학원 토목공학과) ;
  • 박종민 (삼성물산(주) 건설부문 토목사업본부) ;
  • ;
  • 임윤묵 (연세대학교 공과대학 토목공학과)
  • Received : 2010.03.15
  • Accepted : 2010.06.13
  • Published : 2010.08.31

Abstract

Cementitious matrix based composites are vulnerable to the drying shrinkage crack during the curing process. In this study, the drying shrinkage induced fracture behavior of the fiber reinforced concrete is simulated and the effects of the fiber reinforcement conditions on the fracture characteristics are analysed. The numerical model is composed of conduit elements and rigid-body-spring elements on the identical irregular lattice topology, where the drying shrinkage is presented by the coupling of nonmechanical-mechanical behaviors handled by those respective element types. Semi-discrete fiber elements are applied within the rigid-body-spring network to model the fiber reinforcement. The shrinkage parameters are calibrated through the KS F 2424 free drying shrinkage test simulation and comparison of the time-shrinkage strain curves. Next, the KS F 2595 restrained drying shrinkage test is simulated for various fiber volume fractions and the numerical model is verified by comparison of the crack initiating time with the previous experimental results. In addition, the drying shrinkage cracking phenomenon is analysed with change in the length and the surface shape of the fibers, the measurement of the maximum crack width in the numerical experiment indicates the judgement of the crack controlling effect.

References

  1. 김은겸, 최연왕, 차수원, 문대중(2005) 콘크리트 체적변화의 중요성과 대책, 콘크리트학회지, 한국콘크리트학회, 제17권 제4호, pp. 14-24.
  2. 김장호, 원종필, 임윤묵(2008) 재활용 PET병에서 추출한 화이버를 이용한 수축균열 제어용 화이버 콘크리트 개발, 연구보고서, 한국과학재단.
  3. 이창수, 박종혁, 정봉조, 최영준(2009) 물-시멘트비에 따른 경량 콘크리트 및 일반콘크리트의 수축과 습도와의 관계, 대한토목학회논문집, 대한토목학회, 제29권 제4A호, pp. 385-393.
  4. Bazant, Z.P. and Oh, B.H. (1983) Crack band theory for fracture of concrete, Materials and Structures, Vol. 16, pp. 155-176.
  5. Bolander, J.E. and Saito, S. (1997) Discrete modeling of short-fiber reinforcement in cementitious composites, Advanced Cement Based Materials, Vol. 6, pp. 76-86. https://doi.org/10.1016/S1065-7355(97)81590-8
  6. Bolander, J.E. and Saito, S. (1998) Fracture analysis using spring network with random geometry, Engineering Fracture Mechanics, Vol. 61, pp. 569-591. https://doi.org/10.1016/S0013-7944(98)00069-1
  7. Bolander, J.E. and Berton, S. (2004) Simulation of shrinkage induced cracking in cement composite overlays, Cement and Concrete Composites, Vol. 26, pp. 861-871. https://doi.org/10.1016/j.cemconcomp.2003.04.001
  8. Chandlera, H.W., Macpheeb, D.E., Atkinsonb, I., Hendersona, R.J., and Merchant, I.J. (2000) Enhancing the mechanical behaviour of cement based materials, Journal of the European Ceramic Society, Vol. 20, pp. 1129-1133. https://doi.org/10.1016/S0955-2219(99)00285-X
  9. Cox, H.L. (1952) The elasticity and strength of paper and other fibrous materials, British Journal of Applied Physics, Vol. 3, pp. 72-79. https://doi.org/10.1088/0508-3443/3/3/302
  10. Filho, R.D.T., Ghavami, K., Sanjuan, M.A., and England, G.L. (2005) Free, restrained and drying shrinkage of cement mortar composites reinforced with vegetable bres, Cement and Concrete Composites, Vol. 27, pp. 537-546. https://doi.org/10.1016/j.cemconcomp.2004.09.005
  11. Hahn, H.T. and Tsai, S.W (1980) Introduction to Composite Materials, Technomic Pub, Westport, Conn.
  12. Hillerborg, A., Modeer, M., and Petersson P.E. (1976) Analysis of crack formation and crack growth in concrete by means fracture mechanics and finite elements, Cement and Concrete Research, Vol. 6, pp. 773-782. https://doi.org/10.1016/0008-8846(76)90007-7
  13. Kawai, T. (1978) New discrete models and their application to seismic response analysis of structure, Nuclear Engineering and Design, Vol. 48, pp. 207-229. https://doi.org/10.1016/0029-5493(78)90217-0
  14. Kim, J.J., Park, C.G., Lee, S.W., Lee, S.W., and Won, J.P. (2008) Effects of the geometry of recycled PET fiber reinforcement on shrinkage cracking of cement-based composites, Composites: Part B, Vol. 39, pp. 442-450. https://doi.org/10.1016/j.compositesb.2007.05.001
  15. Lin, S.P., Shen, J.H., Han, J.L., Lee, Y.J., Liao, K.H., Yeh, J.T., Chang, F.C., and Hsieh, K.H. (2008) Volume shrinkages and mechanical properties of various ber reinforced hydroxyethyl methacrylate polyurethane unsaturated polyester composites, Composites Science and Technology, Vol. 68, pp. 709-717. https://doi.org/10.1016/j.compscitech.2007.09.017
  16. Naaman, A.E., Namur, G.G., Alwan, J.M., and Najm, H.S. (1991) Fiber pullout and bond slip. I: Analytical study, Journal of Structural Engineering, Vol. 117, pp. 2769-2790. https://doi.org/10.1061/(ASCE)0733-9445(1991)117:9(2769)
  17. Neto, A.A.M., Cincotto, M.A., and Repette, W. (2008) Drying and autogenous shrinkage of pastes and mortars with activated slag cement, Cement and Concrete Research, Vol. 38, pp. 565-574. https://doi.org/10.1016/j.cemconres.2007.11.002
  18. Papayianni, I. and Valliasis, T.H. (2005) Heat deformations of fly ash concrete, Cement and Concrete Composites, Vol. 27, pp. 249-254. https://doi.org/10.1016/j.cemconcomp.2004.02.014
  19. Rots, J.G., Belletti, B., and Invernizzi, S. (2008) Robust modeling of RC structures with an event-by-event strategy, Engineering Fracture Mechanics, Vol. 75, pp. 590-614. https://doi.org/10.1016/j.engfracmech.2007.03.027
  20. Sadouki, H. and van Mier, J.G.M. (1996) Analysis of hygral induced crack growth in multiphase materials, HERON, Vol. 41, No. 4, pp. 267-286.
  21. Schulsona, E.M., Swainsonb, I.P., and Holden, T.M. (2001) Internal stress within hardened cement paste induced through thermal mismatch Calcium hydroxide versus calcium silicate hydrate, Cement and Concrete Research, Vol. 31, pp. 1785-1791. https://doi.org/10.1016/S0008-8846(01)00554-3
  22. Shabana, Y.M., Bruck, H.A., Pines, M.L., and Kruft, J.G. (2006) Modeling the evolution of stress due to dierential shrinkage in powder-processed functionally graded metal-ceramic composites during pressureless sintering, International Journal of Solids and Structures, Vol. 43, pp. 7852-7868. https://doi.org/10.1016/j.ijsolstr.2006.04.003