Journal of the Korean Society for Railway (한국철도학회논문집)

The Korean Society for Railway (한국철도학회)
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Deflection Estimation of a PSC Railroad Girder using Long-gauge Fiber Optic Sensors

Long-gauge 광섬유 센서를 이용한 철도교 PSC 거더의 처짐유추

  • 정원석 (한국철도기술연구원, 궤도토목연구본부) ;
  • 김성일 (한국철도기술연구원, 궤도토목연구본부) ;
  • 김남식 (부산대학교 토목공학과) ;
  • 이희업 (한국철도기술연구원, 궤도토목연구본부)
  • Published : 2006.08.01
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Abstract

This paper deals with the applicability of long-gauge deformation fiber optic sensors (FOS) to prestressed concrete structures. A main motivation is the desire to monitor the deflection of the railway bridges without intervenes of the signal intensity fluctuations. A 25 m long, 1.8 m deep PSC girder was fabricated compositely with 22 cm thick reinforced concrete deck. Two pairs of 3 m long-gauge sensors are attached to the prestressed concrete girder with parallel topology. Using the relationship between curvature and vortical deflection and the quadratic regression of curvatures at the discrete point, it is possible to extrapolate the deflection curve of the girder. The estimated deflection based on the developed method is compared with the results using conventional strain gauges and LVDTS. It has been demonstrated that the proposed instrumentation technique is capable of estimating the vertical deflection and neutral axis position of the prestressed concrete girder up to weak nonlinear region.

Keywords

References

  1. 곽계환,김기수,조선정,곽경헌,김기순(2002),'광섬유 브래그격자 센서를 이용한 철근콘크리트보의 전단-피로 거동에 관한 실험적 연구', 대한토목학회 학술발표회 논문집, pp.651-654
  2. 조남소, 김남식, 이상배 (2001), '광섬유 격자 센서를 이용한 남해대교의 처짐 추정', 대한토목학회 학술발표회 논문집, pp.1-4
  3. 김연태 (2002), '광섬유센서를 이용한 콘크리트 보의 변형률측정 및 균열검출에의 적용성', 대한토목학회 논문집, 제22권, 2-A호, 대한토목학회, pp.221-227
  4. Tennyson R.C., Mufti A.A., Rizkalla S., Tadros G., and Benmokrane B. (2001), 'Structural health monitoring of innovative bridges in Canada with fiber optic sensors', Smart Mater. Struct., Vol.10, pp.560-573 https://doi.org/10.1088/0964-1726/10/3/320
  5. Ansari, F. (1997), 'State-of-the-art in the applications of fiber-optic sensors to cementitious composites', Cement and Concrete Composite, Vol.19, pp.3-19 https://doi.org/10.1016/S0958-9465(96)00038-8
  6. Leung C.K.Y. (2001), 'Fiber optic sensors in concrete: the future?', NDT & E International, Vol.34, No.2, pp.85-94 https://doi.org/10.1016/S0963-8695(00)00033-5
  7. Vurpillot S, Kreuger, G., Benouaich D, Clement D, and Inaudi D (1998), 'Vertical deflection of a pre-stressed concrete bridges obtained using deformation sensors and inclinometer measurements', ACI Structural Journal, Vol.95, No.5, pp.518-26
  8. Inaudi D. SOFO System Ver. 6 User Manual. Smartec SA, 1999, Switzwerland
  9. Kim, N.S., Cho, N.S. (2004), 'Estimating deflection of a simple beam model using fiber Optic Bragg-grating sensors. Experimental Mechanics', Vol.44, No.4, 2004, pp.433-439 https://doi.org/10.1007/BF02428097