한국전산구조공학회논문집 (Journal of the Computational Structural Engineering Institute of Korea)

  • 제30권2호
  • /
  • Pages.137-143
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  • 2017
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  • 1229-3059(pISSN)
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  • 2287-2302(eISSN)
한국전산구조공학회 (Computational Structural Engineering Institute of Korea)
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폭발하중을 받는 콘크리트 보의 요소의존성 최소화 인장기준식

A Tensile Criterion to Minimize FE Mesh-Dependency in Concrete Beam under Blast Loading

  • 곽효경 (한국과학기술원 건설 및 환경공학과) ;
  • 강한글 (한국과학기술원 건설 및 환경공학과)
  • Kwak, Hyo-Gyoung (Department of Civil and Environmental Engineering, KAIST) ;
  • Gang, HanGul (Department of Civil and Environmental Engineering, KAIST)
  • 투고 : 2016.12.29
  • 심사 : 2017.01.10
  • 발행 : 2017.04.28
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초록

본 논문에서는 파괴에너지이론에 기초하여 요소의존성을 최소화할 수 있는 인장파괴기준식을 제안하고 HJC(holmquist johnson cook), CSC(continuous surface cap), Orthotropic 모델을 이용한 폭발수치해석을 통해 기준식을 검증하였다. 폭발하중으로 인한 RC 보의 시간에 따른 중앙지점의 처짐을 실험결과와 비교하였다. 그 결과 기준식을 통해 산정된 파괴변형률을 수치해석상에 적용해줌으로써 해석결과의 요소의존성이 감소하였고 해의 정확성 또한 향상되는 것을 파악할 수 있었다.

A tensile failure criterion that can minimize the mesh-dependency of simulation results on the basis of the fracture energy concept is introduced, and conventional plasticity based damage models for concrete such as CSC model and HJC model, which are generally used for the blast analyses of concrete structures, are compared with orthotropic model in blast test to verify the proposed criterion. The numerical prediction of the time-displacement relations in mid span of the beam during blast loading are compared with experimental results. Analytical results show that the numerical error is substantially reduced and the accuracy of numerical results is improved by applying a unique failure strain value determined according to the proposed criterion.

키워드

참고문헌

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