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

Computational Structural Engineering Institute of Korea (한국전산구조공학회)
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Simplified Analysis of Superstructure Section Considering Diaphragm and Optimum Design Conditions for ILM Bridge

다이아프램이 고려된 ILM 교량 상부단면의 단순해석 및 최적설계조건

  • Lee, Hwan-Woo (Department of Civil Engineering, Pukyong National University) ;
  • Park, Yong-Jin (Department of Civil Engineering, Pukyong National University)
  • Received : 2014.09.01
  • Accepted : 2014.09.27
  • Published : 2014.10.31
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Abstract

ILM(Incremental Launching Method) bridges pass both the middle of spans and supports during launching. The launching noses are used to minimize the maximum positive moments and negative moments of the superstructure occurring during launching for ILM bridges. In this study, the simplified analysis formula considering diaphragm to calculate the bending moment that occurs during launching is induced and analyzes the optimum design conditions considering diaphragm. The accuracy of the proposed simplified analysis formular compared to the MIDAS Civil has an error of less than 5%. There is a difference up to 13% in the moment between the cases when the diaphragm is considered and is not. In addition, the criteria for deciding the unit weight of equivalent cross section and average stiffness value of equivalent cross section that can be applied to the simplified analysis formula is proposed. In this study, an effective way to optimize the launching nose is proposed that the optimum design is taken in the condition of minimizing the negative moment because of the mechanic characteristic of ILM bridges.

ILM 교량은 압출되는 동안 상부의 단면이 지간의 중앙부와 지점부를 모두 통과한다. 따라서 발생되는 최대 정모멘트 및 최대 부모멘트를 효과적으로 제어하기 위해서 압출추진코를 이용한다. 이 연구에서는 압출중 상부구조물에 발생하는 휨모멘트를 계산할 수 있는 다이아프램이 고려된 단순 해석식을 개발하였다. 또한 다이아프램이 고려된 압출추진코의 최적설계조건에 관하여 분석하였다. 단순 해석식을 MIDAS Civil과 비교한 결과 대부분의 경우 0.5%이하의 오차를 가지는 정확성을 확인하였다. 다이아프램의 영향을 고려했을 경우와 고려하지 않았을 경우 사례교량에서 최대 13%의 휨모멘트 차이를 보였다. 또한, 단순 해석식에 적용시킬 등가 등단면의 단위중량 및 평균강성값을 결정할 수 있는 기준을 제시하였다. 이 연구에서는 ILM 교량의 압출중 역학특성으로 인하여 부모멘트 최소화 조건만을 사용하는 것이 압출추진코 최적설계를 위한 효과적인 방법으로 판단하였다.

Keywords

References

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