Journal of the Korean Geotechnical Society (한국지반공학회논문집)

Korean Geotechnical Society (한국지반공학회)
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Temperature Compensation on the Cone Tip Resistance by Using FBG Temperature Transducer

FBG센서를 이용한 콘 선단저항력의 온도영향 보상

  • Kim, Rae-Hyun (School of Civil, Environmental, and Architectural Engrg., Korea Univ.) ;
  • Lee, Jong-Sub (School of Civil, Environmental, and Architectural Engrg., Korea Univ.) ;
  • An, Shin-Whan (School of Civil, Environmental, and Architectural Engrg., Korea Univ.) ;
  • Lee, Woo-Jin (School of Civil, Environmental, and Architectural Engrg., Korea Univ.)
  • 김래현 (고려대학교 건축.사회환경공학과) ;
  • 이종섭 (고려대학교 건축.사회환경공학과) ;
  • 안신환 (고려대학교 건축.사회환경공학과) ;
  • 이우진 (고려대학교 건축.사회환경공학과)
  • Received : 2009.02.20
  • Accepted : 2009.10.12
  • Published : 2009.10.31
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Abstract

As the measurement of strain-gage type cone penetrometer is influenced by the temperature change during penetration, the temperature is a factor producing an error of the cone tip resistance. In this study, the 0.5 mm diameter temperature transducer and 7 mm diameter micro cone penetrometer are manufactured by using FBG sensors to evaluate the effect of temperature on the cone tip resistance. Design concepts include the cone configuration, sensor installation and the temperature compensation process. The test shows that the tip resistance measured by strain gauge is affected by the temperature change. The error of the tip resistance increases with an increase in temperature change, while the temperature effect on the tip resistance of FBG cone is effectively compensated by using FBG temperature transducer. Temperature compensated tip resistance of the strain gauge cone shows the good matched profile with FBG cone which performs real-time temperature compensation during penetration. This study demonstrates that the temperature compensation by using FBG sensor is an effective method to produce the more reliable cone tip resistance.

전기저항식 변형율계를 이용한 콘 관입시험기는 온도 변화에 의해 선단저항력이 달라진다-본 연구에서는 FBG센서를 이용하여 직경 0.5mm의 온도센서와 직경 7mm의 마이크로콘을 제작하여 온도의 변화가 콘 선단저항력에 미치는 영향을 평가하고 이를 효과적으로 보상하고자 하였다-광섬유 마이크로콘과 온도센서는 콘의 구조, 센서 부착 위치 및 광섬유를 이용한 온도보상법 등을 고려하여 제작하였다-온도영향 시험결과, 전기저항식 변형율계의 콘 선단저항력은 온도에 의해 영향을 받으며 온도 차이가 클수록 오차도 증가하는 것으로 나타났다. 반면, FBG센서에서 측정된 콘 선단저항력은 FBG 온도센서를 이용하여 효과적으로 온도의 영향을 보상할 수 있었다. 또한 온도 보상을 실시한 전기저항식 변형율계의 콘 선단저항력은 심도에 따라 일정한 분포를 보였으며 관입과 동시에 온도의 영향이 보상되는 FBG센서의 결과와도 매우 유사한 것으로 나타났다. 본 연구를 통해 온도 변화가 선단저항력에 미치는 영향을 평가하였으며, FBG센서를 이용하여 효과적으로 온도 영향을 보상할 수 있음을 확인하였다.

Keywords

References

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