Numerical Simulation for the Variation of the Fiber Orientation Distribution according to the Flow of High-Flow Steel-Fiber Reinforced Mortar

고유동 강섬유보강 모르타르의 유동에 따른 섬유의 방향성 분포특성 변화의 예측

  • 강수태 (한국건설기술연구원 구조교량연구실) ;
  • 김진근 (한국과학기술원 건설 및 환경공학과)
  • Received : 2009.09.28
  • Accepted : 2009.11.04
  • Published : 2009.12.30

Abstract

High-flow steel-fiber reinforced mortar may induce a certain fiber orientation distribution in the process of placing and thus have an influence on the tensile properties. In this paper, the variation of the fiber orientation distribution according to the flow of high-flow steel-fiber reinforced mortar was estimated in numerical simulation. The analytical results present that the major variation of fiber orientation distribution is made within 150mm of flow distance, thereafter the tendency of the fiber orientation distribution is not noticeable even though the peak of distribution density in the orientation parallel to the flow direction get bigger along the distance. Considering the close relation between the fiber orientation and the tensile behavior of composite, prediction of fiber orientation distribution make it possible to predict the variation in the tensile behavior of high-flow steel-fiber reinforced mortar according to the flow.

고유동 강섬유보강 모르타르는 타설과정에서 특정한 섬유 방향성 분포를 가질 수 있으며, 이에 따라 재료의 인장거동 특성에 영향을 미칠 수 있다. 본 연구에서는 고유동 강섬유보강 모르타르의 타설단계에서의 유동에 따른 강섬유의 섬유 방향성 분포의 변화를 해석적으로 구하였다. 해석결과에 따르면 180mm 간격으로 나란히 놓여진 두 평판 사이에 흐르는 모르 타르의 전단흐름에 의한 섬유의 방향성 변화는 초기 150mm이내에서 크게 발생하는 것을 확인할 수 있었으며, 이후에서는 방향성 분포의 경향은 크게 변하지 않으며, 다만 흐름방향에 나란한 섬유의 밀도가 집중적으로 커지는 것을 볼 수 있었다. 섬유의 방향성과 섬유보강 복합체의 인장거동과 밀접한 관련성을 고려할 때, 이와 같은 방향성의 예측을 바탕으로 유동에 따른 고유동 강섬유보강 모르타르의 인장거동 변화의 예측이 가능할 것이다.

Keywords

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