Long Term Monitoring of Prestressing Tension Force in Post-Tension UHPC Bridge using Fiber Optical FBG Sensor

FBG 광섬유센서가 내장된 7연 강연선을 이용한 포스트텐션 UHPC 교량의 긴장력 장기모니터링

  • Received : 2015.10.17
  • Accepted : 2015.11.24
  • Published : 2015.12.29


This paper presents results of one-year monitoring on prestressing force of a 7-wire steel post-tensioning strand which is installed in a UHPC(ultra high performance concrete) bridge with 11.0 m long, 5.0 m wide, and 0.6 m high by using a FBG-encapsulated 7-wire steel strand. The initial prestressing forces and the prestress changes during a vehicle load test were measured using the FBG-encapsulated strand. The results show that the FBG-encapsulated 7-wire strand is very effective for monitoring the prestress forces even the change in the tension force is very small. Additionally, it was indicated that selection of the thermal expansion coefficient which is used for the temperature correction shall be carefully carried out.


FBG sensor;PSC grider;prestressing strand;tension force monitoring;temperature compensation


  1. Calvert, S., Mooney, J. (2004) Bridge Structural Health Monitoring System using Fiber Grating Sensors: Development and Preparation for a Permanent Installation, SPIE Proc., 5391, pp.61-71.
  2. Hong, C.S., Ryu, C.Y., Koo, B.Y., Kim, C.G., Yun, S.H. (2000) Strain Monitoring of Smart Bridge using Fiber Bragg Grating Sensor System with Wavelength-Swept Fiber Laser, SPIE Proc., 3988, pp.371-379.
  3. Inaudi, D. (2009) Overview of 40 Bridge Structural Health Monitoring Projects, International Bridge Conference, IBC 2010.
  4. Kim, S.T., Park, Y.H., Park, Y.H., Cho, K.H., Cho, J.R. (2015) A Sensor-Type PC Strand with an Embedded FBG Sensor for Monitoring Prestress Forces, Sensors, 15, pp.1060-1070.
  5. Kim, J.M., Kim, H.W., Park, Y.H., Kim, Y.S. (2010) Tension Monitoring of a Prestressing Strand for Concrete Bridge using In-Tendon FBG Sensors, Proc. IABMAS-2010, pp.205-210.
  6. Kim, J.M., Kim, H.W., Park, Y.H., Yang, I.H., Kim, Y.S. (2012) FBG Sensors Encapsulated into 7-Wire Steel Strand for Tension Monitoring of a Prestressing Tendon, Adv. Struct. Eng., 15(6), pp.907-918.
  7. Lau, K.T. (2003) Fibre-Optic Sensors and Smart Composites for Concrete Applications, Mag. Concr. Res., 55(1), pp.19-34.
  8. Nellen, P.M., Bronnimann, R., Frank, A., Mauron, P., Sennhauser, U. (1999) Structurally Embedded Fiber Bragg Gratings: Civil Engineering Application, SPIE Proc., 3860, pp.44-54.
  9. Maaskant, R., Alavie, T., Measures, R.M., Tadros, G., Rizkalla S-H., Guha-Thakurta, A. (1997) Fiber-Optic Bragg Grating Sensors for Bridge Monitoring, Cement and Concrete Composites, 19(1), pp.21-33.
  10. Othonos, A., Kalli, K. (1999) Fiber Bragg Gratings, Artech House, London.
  11. Ren, L., Li, H.N., Sun, L., Li, D.S. (2005) Development of Tube-Packaged FBG Strain Sensor and Application in the Vibration Experiment of Submarine Pipeline Model. SPIE Proc., pp.98-103.
  12. Tennyson, R.C., Mufti, A.A., Rizkalla, S., Tadros, G., Benmokrane, B. (2001) Structural Health Monitoring of Innovative Bridges in Canada with Fiber Optic Sensors, Smart Mater. & Struct., 10(3), pp.1-22.
  13. Udd, E. (1996) Fiber Optic Smart Structures, John Wiley and Sons, Inc.
  14. Xuan, F.Z., Tang, H., Tu, S.T. (2009) In Situ Monitoring on Prestress Losses in the Reinforced Structure with Fiber-Optic Sensors, Measurement, 42(1), pp.107-111.
  15. Zhou, Z., Zhang, Z., Deng, N., Zhao, X., Li, D., Wang, C., OU, J. (2005) Applications of FRPOFBG Sensors on Bridge Cables, SPIEProc., pp.668-677.
  16. Zhou, Z., OU, J. (2004) Development of FBG Sensors for Structural Health Monitoring in Civil Infrastructures, Sensing Issues in Civil Structural Health Monitoring, pp.197-207.
  17. Zhang, Z., Zhou, Z., Wang, C., Ou, J. (2006) Long-Term Monitoring FBG-Based Cable Load Sensor, SPIE Proc., 6167, pp.1-7.

Cited by

  1. Fundamental Experiment to Verify the Resolution of Hetero-core Fiber Optic Sensor for the Prestress Measurement vol.31, pp.5, 2018,


Supported by : 국토교통과학기술진흥원, 한국건설기술연구원