Journal of the Korea Academia-Industrial cooperation Society (한국산학기술학회논문지)

The Korea Academia-Industrial cooperation Society (한국산학기술학회)
권호 표지
DOI QR코드

DOI QR Code

Study on Stress Recovery Length of 7-Wire Strand due to Local Damage

강연선의 국부적 손상에 따른 응력 회복길이 분석 연구

  • Seo, Dong-Woo (Korea Institute of Civil Engineering and Building Technology (KICT)) ;
  • Kim, Byung-Chul (Korea Institute of Civil Engineering and Building Technology (KICT)) ;
  • Jung, Kyu-San (Korea Institute of Civil Engineering and Building Technology (KICT)) ;
  • Na, Wongi (Korea Institute of Civil Engineering and Building Technology (KICT)) ;
  • Park, Ki-Tae (Korea Institute of Civil Engineering and Building Technology (KICT))
  • Received : 2017.10.11
  • Accepted : 2017.12.08
  • Published : 2017.12.31
Download PDF
⟨ Previous Next ⟩

Abstract

This study examined the stress recovery length due to the local damage of a 7-wire strand, which is applied widely to PSC (Post Tensioned Concrete) bridges and cable-stayed bridges. The 7-wire strand is a multiple stranded steel of PC prestressing strand. Owing to the nature of the material, it is damaged continuously after completion with corrosion being the main cause of damage. On the other hand, due to its structural characteristics, it is difficult to grasp the degree of damage inside the cable and the pattern of stress variation. In the case of cables applied to bridges, the parts that are susceptible to corrosion are generated depending on the water supply and installation shape, which may cause local damage. This study analyzed the tendency of performance degradation and stress recovery length according to local damage of a 7-wire strand, which is applied mainly to bridge post-tensioning or stay cables. This study developed a computer-based simulation model that was validated with experimental results. The model developed in this study can be used to evaluate the safety level and estimate the remaining life span of P SC bridges or cable-stayed bridges.

본 연구는 PSC(Post Tensioned Concrete) 교량 및 사장교(Cable Stayed Bridge) 등에 많이 적용되는 강연선의 국부적 손상에 따른 응력 회복길이를 분석하였다. 강연선은 PC 강선(Prestressing Strand)을 여러 줄을 꼬은 강재이며, 재료의 특성상 준공후 지속적으로 손상이 발생하며 부식 등이 주요 손상원인이다. 이에 따른 손상에 따른 성능저하가 발생하지만, 구조적인 특성상 케이블 내부의 손상 정도 및 응력 변화 패턴을 파악하기 어렵다. 교량에 적용된 케이블의 경우 설치 형상에 따라 채수 등에 따라 부식에 취약한 부분이 발생하며, 이로 인해 국부적인 손상이 발생할 수 있다. 본 연구는 교량 Post-Tensioning 또는 케이블 사장재에 주로 적용되는 강연선(7-Wire Strand)의 국부적 손상에 따른 성능저하 경향 및 응력 회복길이를 FEA 해석을 통하여 분석하였다. 향후 본 연구에서 구축하고자 하는 해석모델을 활용하여 PSC 교량 및 사장교 케이블 등의 안전성 평가 및 잔존수명 예측에 활용될 수 있을 것으로 사료된다.

Keywords

Acknowledgement

Supported by : 한국표준과학연구원, 한국건설기술연구원

References

  1. Y. J. Chiang, "Characterizing simple stranded wire cables under axial loading," Journal of Finite Elements in Analysis and Design, Vol. 24, pp. 49-66, 1996. DOI: https //doi.org/10.1016/S0168-874X(97)80001-E
  2. W. G. Jiang, J. L. Henshall, "The analysis of termination effects in wire strand using the finite element method," Journal of Strain Analysis, Vol. 34, No. 1, pp 31-38, 1999. DOI: https //doi.org/10.1243/0309324991513605
  3. G. Shibu, K. V. Mohankumar, S. Devendiran, "Analysis of a three layered straight wire rope strand using finite element method," Proceedings of the World Congress on Engineering, 2011.
  4. I. Gerdemeli, S. Kurt, A. S. Anil, "Analysis with finite element method of wire rope," Faculty of Mechanical Engineering, Istanbul Technical University, 2012.
  5. ANSYS, Inc. ANSYS Workbench 11 User's Guide. 2009.
  6. K. T. Park, O. I. Kwon, J. H. Lee, D. W. Seo, W. G. Na, J. S. Park, T. H. Kim, "Evaluation techniques for cable system/earth anchor/steel corrosion by micro and macro measured data," Internal Report, Korea Institute of Civil Engineering and Building Technology, 2016.
  7. MIDAS, Inc., MIDAS FEA User's Guide, 2017.