Longitudinal Stress Distributions around Construction Joints of PSC Bridge Girders

PSC 교량의 시공이음부 종방향 응력 분포

  • 임정순 (경기대학교 토목.환경 공학부) ;
  • 이수근 (경기대학교 토목공학과) ;
  • 채성태 (하이콘엔지니어링 구조부)
  • Published : 2002.09.30

Abstract

There exist many construction joints in segmentally constructed bridge girders. It is required coupling of tendons or overlapping of tendons to introduce continuous prestress through several spans of bridges. Even though tendon coupling method is easier to use in practice, some cracking problems around construction joints have been reported and complicated stress states around construction joints in PSC girders is not clearly investigated. The purpose of this paper is to investigate in detail the complicated longitudinal stress distributions around the construction joints in prestressed concrete girders with tendon couplers. To this end, a comprehensive experimental program has been set up and a series of specimens have been tested to identify the effects of tendon coupling and segmental construction of bridge sections. The present study indicates that the longitudinal stress distributions of PSC girders with tendon couplers are quite different from those of PSC girders without tendon couplers. The longitudinal compressive stresses introduced by prestressing are greatly reduced around coupled joints according to tendon coupling ratios.

다양한 공법으로 널리 시공되고 있는 프리스트레스트 콘크리트(PSC) 연속 교량의 단면에는 시공이 음이 발생하게 된다. 이러한 시공이음부에서 연속적인 프리스트레스 하중을 도입하기 위해서는 텐던을 겹침이음(overlapping)하거나 텐던 커플러를 사용하는 방법이 사용되며, 후자의 경우는 시공이 음의 정착부 배근의 단순화와 효율적으로 텐던을 사용할 수 있는 장점이 있다. 본 연구의 목적은 텐던 커플러를 사용한 PSC 교량의 시공이음부의 종방향 응력 분포를 규명하는 데 있으며, 이를 위해 텐던 연속과 단면의 분할 시공 효과를 고려한 실험과 유한요소 해석을 수행하였다 연구결과 텐던 커플러를 사용한 시공이음부의 응력 상태는 텐던 커플러를 사용하지 않은 경우에 비해 종방향 응력상태와 다르게 나타나고 있다. 특히 구조적으로 문제가 되는 종방향 압축응력은 시공이음부에서 텐던 연결비율이 증가함에 따라 크게 감소한다.

Keywords

References

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