Journal of the Korean GEO-environmental Society (한국지반환경공학회 논문집)

Korean Geo-Environmental Society (한국지반환경공학회)
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Development and Application of Cone Penetrometer with Impact Penetration Rod for Evaluation of Track Substructure

철도궤도 하부구조물 평가를 위한 타격식 관입 롯드가 체결된 콘 관입기의 개발 및 적용

  • Hong, Wontaek (School of Civil, Environmental and Architectural Engineering, Korea University) ;
  • Byun, Yonghoon (School of Civil, Environmental and Architectural Engineering, Korea University) ;
  • Kim, Sangyeob (School of Civil, Environmental and Architectural Engineering, Korea University) ;
  • Choi, Chanyong (Korea Railroad Research Institute) ;
  • Lee, Jongsub (School of Civil, Environmental and Architectural Engineering, Korea University)
  • Received : 2014.11.10
  • Accepted : 2015.01.14
  • Published : 2015.02.01
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Abstract

To minimize the cost of maintenance, repair and over-design of track substructure, an accurate evaluation of strength and stiffness of the track substructure is necessary. In this study, a cone penetrometer with impact penetration rod (CPI) is developed for the evaluation of track substructure. For applicability test, the chamber and field tests were performed. As the experimental results of the CPI, dynamic cone penetration endex (DCPI), cone tip resistance ($q_c$), friction resistance ($f_s$) and friction ratio (Fr) were obtained. In the chamber test, the experimental results show reasonable values for the simulated track substructure. In the field test, the CPI clearly detects the interface between the ballast and the subgrade. Also, discontinuous layers are detected in the subgrade. It is expected that the developed CPI may be an effective tool for the evaluation of track substructure by evaluating the ballast layer by dynamic penetration and the subgrade by static penetration of the inner rod.

철도궤도 하부구조물의 유지, 보수 및 과다설계에 따른 비용을 최소화하기 위하여 궤도 하부구조물의 강도 및 강성특성에 대한 정확한 평가는 필수적이다. 본 연구에서는 궤도 하부구조물의 상태를 평가하기 위한 콘 관입기(CPI)를 개발하였으며, 적용성 검증을 위하여 실내실험과 현장실험을 수행하였다. CPI를 이용한 철도궤도 하부구조물 평가의 결과로서 획득되는 결과는 동적 콘관입지수(DCPI), 원추관입저항력($q_c$), 마찰저항력($f_s$) 및 마찰력비(Fr)이다. 실험결과, 실내실험의 경우 도상자갈층에서 획득한 동적 콘 관입지수와 상부노반층에서 획득한 원추관입저항력, 마찰저항력 및 마찰비는 조성한 시료에 대하여 신뢰할 만한 결과를 보였다. 현장실험의 경우 도상자갈층의 경계면을 명확히 구분해 내었으며, 상부노반층의 불연속면을 감지하였다. 본 연구에서 개발된 CPI는 동적 관입과 정적 관입 방법을 이용함으로써 궤도 하부구조물 평가에 유용한 방법이 될 것이라 기대된다.

Keywords

References

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