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Permeability of Magnetic Flux of PS Steel for Variation of Stress and Temperature

긴장재의 응력 및 온도변화에 따른 자속투과율

  • 박진수 (경남대학교 사회기반시스템공학과) ;
  • 김병화 (경남대학교 건설시스템공학과)
  • Received : 2021.11.19
  • Accepted : 2022.02.07
  • Published : 2022.06.01

Abstract

An experimental study was conducted to investigate the effect of applied tensile force and temperature on the permeability of magnetic flux in prestressing steel. The permeability of magnetic flux is the ratio at which the magnetic flux between two points passes. The prestressing steel used in these experiments included a 7-mm PS wire mainly used for cable-stayed bridges and a 12.7-mm PS strand for prestressed concrete bridges. The experiments to extract the permeability of the magnetic flux of steel wire and strand were conducted under various tensile levels and temperature conditions. From the experimental results, it was observed that the permeability of magnetic flux of the PS tension material was linearly proportional to the applied tensile stress level, and inversely proportional to the temperature. If the experimental relationship among the magnetic permeability, temperature, and prestressing ratio of a PS tension material is known in advance, the current tension stress level on PS members can be evaluated by measuring solely the magnetic permeability and temperature.

PS 긴장재의 긴장률, 온도 그리고 자속투과율의 상호관계가 실험적으로 조사되었다. 자속투과율은 두 지점 사이의 자속이 통과하는 비율이다. 실험에 사용된 긴장재는 케이블 교량에 주로 사용되는 ϕ7 mm 고강도 강선과 PSC 긴장재로 사용되는 ϕ12.7 mm 강연선이다. 다양한 도입 긴장률과 온도 조건하에서 강선과 강연선의 자속투과율 실험이 수행되었다. 실험결과로부터, PS 긴장재의 자속투과율은 도입 긴장률에 선형 비례하고, 온도에 선형 반비례함을 알 수 있다. PS 긴장재의 자속투과율-온도-긴장률 사의의 실험적 관계를 미리 알게 되면, 현장에서 PS 강재의 자속투과율과 온도만을 계측함으로써, PS 긴장재의 현재 긴장응력 수준을 변형률 계측 없이 직접 평가할 수 있다.

Keywords

Acknowledgement

이 연구는 한국연구재단(NRF-2018R1D1A1B07043521)의 지원을 받았습니다. 본 논문은 2021 CONVENTION 논문을 수정·보완하여 작성되었습니다

References

  1. Chen, D., Zhang, B., Li, X., Tu, C., Yuan, C., Li, W., Zhou, Z. and Liang, Z. (2018). "A stress measurement method for steel strands based on LC oscillation." Advances in Materials Science and Engineering, Vol. 2018, pp. 1-8.
  2. Dang, N. L., Huynh, T. C. and Kim, J. T. (2019). "Local strand-breakage detection in multi-strand anchorage system using an impedance-based stress monitoring method-feasibility-study." Sensors, Vol. 19, No. 5, pp. 1054. https://doi.org/10.3390/s19051054
  3. Griffiths, D. J. (2019). Introduction to electrodynamics, Bookshill.
  4. Hiba, A. J. and Branko, G. (2019). "Monitoring of prestressing forces in prestressed concrete structures-An overview." Structural Control Health Monitoring, Vol. 26, No. 8, pp. 1-27.
  5. Instron (2012). Instron 4485, Available at: https://www.instron.com/en/ (Accessed: November 19, 2021).
  6. Jeon, K. Y., Kwon, S. H., Kim, K. D., Baek, J. B., Kim, J. K. and Park, S. H. (2019). "Monitoring method for pre-stressing temporary steel bar of FCM using EM sensor." Journal of the Korean Society of Civil Engineers, KSCE, Vol. 67, No. 12, pp. 76-82.
  7. JKCORP (2021). Outlet type digital thermostat, Available at: https://smartstore.naver.com/_jkcorporation (Accessed: November 19, 2021).
  8. KIKUSUI (2020). PCR-500M, Available at: https://www.kikusui.co.jp/en/ (Accessed: November 19, 2021).
  9. Kim, B. H. and Park, T. H. (2007). "Estimation of cable tension force using the frequency-based system identification method." Journal of Sound and Vibration, Vol. 304, No. 3-5, pp. 660-676. https://doi.org/10.1016/j.jsv.2007.03.012
  10. Kim, B. H., Joh, C. B. and Lee, D. H. (2013). "A feasibility study for estimating prestressed stress on a steel wire Using permeability of magnetic flux." Journal of the Earthquake Engineering Society of Korea, Vol. 17, No. 93, pp. 219-225. https://doi.org/10.5000/EESK.2013.17.5.219
  11. Kim, D. H., Hong, Y. K., Seo, D. W. and Jung, S. K. (2021). "Safety diagnosis and evaluation technique for PSC bridges using acoustic emission technique." Journal of the Korean Society for Nondestructive Testing, Vol. 41, No. 1, pp. 25-38. https://doi.org/10.7779/JKSNT.2021.41.1.25
  12. Kim, D. H., Hong, Y. K., Seo, D. W. and Park, T. K. (2019a). "Integrity evaluation technology of PSC bridge tendons using acoustic emission technique." Journal of the Korean Society for Nondestructive Testing, Vol. 39, No. 1, pp. 37-44. https://doi.org/10.7779/jksnt.2019.39.1.37
  13. Kim, D. H., Hong, Y. K., Seo, D. W. and Kim, J. H. (2019b). "Fracture behavior of internal tendon in PSC structure using acoustic emission technique." Journal of the Korean Society for Nondestructive Testing, Vol. 39, No. 6, pp. 362-368. https://doi.org/10.7779/jksnt.2019.39.6.362
  14. Kim, K. J., Park, Y. S. and Park, S. W. (2020). "Development of artificial neural network model for estimation of cable tension of cable-Stayed bridge." Journal of the Korea Academia-Industrial Cooperation Society, Vol. 21, No. 3, pp. 414-419. https://doi.org/10.5762/KAIS.2020.21.3.414
  15. Kim, J. K., Park, J. Y., Zhang, A., Lee, H. W. and Park. S. H. (2015a). "Prestressing loss management for PSC girder tendon based on EM sensing." Journal of the Computational Structural Engineering Institute of Korea, Vol. 28, No. 4, pp. 369-374. https://doi.org/10.7734/COSEIK.2015.28.4.369
  16. Kim, S. T., Park, Y. H., Park, S. Y., Cho, K. H. and Cho, J. R. (2015b). "A sensor-type PC strand with an embedded FBG sensor for monitoring prestress forces." Sensors, Vol. 15, No. 1, pp. 1060-1070. https://doi.org/10.3390/s150101060
  17. Kim, H. W., Kim, J. M., Choi, S. Y., Park, S. Y. and Lee, H. W. (2015c). "Long term monitoring of prestressing tension force in post-tension UHPC bridge using fiver optical FBG sensor." Journal of the Computational Structural Engineering Institute of Korea, Vol. 28, No. 6, pp. 669-706.
  18. KONGSUNG (2021). W-80-HOT-JET, Available at: http://www.kongsung.net/ (Accessed: November 19, 2021).
  19. Li, X., Zhang, B., Yuan, C., Tu, C., Chen, D., Chen, Z. and Li, Y. (2018). "An electromagnetic oscillation method for stress measurement of steel strands." Measurement, Vol. 125, pp. 330-335. https://doi.org/10.1016/j.measurement.2018.05.014
  20. Na, W. S. and Baek, J. D. (2018). "A review of the piezoelectric electromechanical impedance based structural health monitoring technique for engineering structures." Sensors, Vol. 18, No. 5, pp. 1307. https://doi.org/10.3390/s18051307
  21. National Instruments (2012). NI9239, Available at: https://www.ni.com/ko-kr.html (Accessed: November 19, 2021).
  22. Nguyen, D. H. and Kim, B. H. (2020). "Experimental relationship between electrical impedance of a steel wire and applied stress, temperature, and excited frequency." Journal of the Korean Society of Civil Engineers, KSCE, Vol. 40, No. 2, pp. 183-189. https://doi.org/10.12652/Ksce.2020.40.2.0183
  23. Park, J. H., Hong, D. S., Kim, J. T., Na, W. B. and Cho, H. M. (2010). "A study on applicability of wireless impedance sensor nodes technique for tensile force monitoring of structural cables." Joural of Korean Society of Steel Construction, Vol. 22, No. 1 pp. 21-31.
  24. Park, J. H., Kim, J. K., Eum, K. Y. and Park, S. H. (2019). "Low-voltage EM (Elasto-Magnetic) sensing technique for tensile force management of PSC (Prestressed Concrete) internal tendon." Journal of the Computational Structural Engineering Institute of Korea, Vol. 32, No. 2, pp. 87-92. https://doi.org/10.7734/COSEIK.2019.32.2.87
  25. Ryu, J. Y., Huynh, T. C. and Kim, J. T. (2019). "Tension force estimation in axially loaded members using wearable piezoelectric interface technique." Sensors, Vol. 19, No. 1, pp. 47. https://doi.org/10.3390/s19010047
  26. Shen, S., Wang, Y., Ma, S. L., Huang, D., Wu, Z. H. and Guo, X. (2018). "Evaluation of prestress loss distribution during pre-tensioning and post-tensioning using long-gauge fiber bragg grating sensors." Sensors, Vol. 18, No. 12, pp. 4106. https://doi.org/10.3390/s18124106
  27. Zhang, B., Tu, C., Li, X., Cui, H. and Zheng, G. (2019). "Length effect on the stress detection of prestressed steel strands based on electromagnetic oscillation method." Sensors, Vol. 19, No. 12, pp. 2782. https://doi.org/10.3390/s19122782
  28. Zhu, X. and Scalea, F. L. (2016). "Sensitivity to axial stress of electro mechanical impedance measurements." Experimental Mechanics, Vol. 56, No. 9, pp. 1599-1610. https://doi.org/10.1007/s11340-016-0198-2