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2016 Vol.32, Issue 4 Preview Page
Development of a Flat-type TDR System for Compaction Control

다짐관리를 위한 판형 TDR 시스템 개발

Minwoo Song1
,
Chanyong Choi2
,
Daehyeon Kim3*
송 민우1
,
최 찬용2
,
김 대현3*
1Graduate Student, Dept. of Civil Engrg., Chosun Univ.
2Senior Researcher, Advanced Infrastructure Research Team, Korea Railroad Research Institute
3Associate Prof., Dept. of Civil Engrg., Chosun Univ.
1조선대학교 토목공학과 석사과정
2한국철도기술연구원 첨단인프라연구팀 선임연구원
3조선대학교 토목공학과 부교수
*교신저자. *Corresponding Author. 
30 April 2016. pp. 51-61
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Abstract

In this study, a new TDR system equipped with a flat type probe has been developed to improve the currently used TDR system that measures dry density and water content. To verify the developed TDR system, TDR tests were conducted on Jumunjin sand and three typical soils. Also, additional tests were performed to measure the correction value of the developed probe. Using the TDR signals, dielectric constant, electrical conductivity and soil constants were derived. The water content and dry density of the soils were determined through the TDR tests. The applicability of the TDR system was examined by comparison of the measured values by TDR and the real values. The values of dry density and water content were found to have about 2% and 0.5% error, respectively. Based on the test results, it has been confirmed that the new TDR system can be used as an alternative to the previous TDR system as it can measure the dry density and the water content with reasonable accuracy, leading to significant time and cost savings.

Keywords
TDR
Nondestructive system
water content
dry density

본 연구는 최근 국내･외로 지반공학적 특성 평가 연구가 진행되고 있는 TDR(Time Domain Reflectometry)을 개선하기 위하여 진행되었고, 이를 통해 30.48cm×25.4cm의 크기를 갖는 판형 Probe를 제작하였다. 개발한 TDR 시스템을 검증하기 위하여 주문진 표준사 및 세 종류의 일반적인 시료를 대상으로 실내실험을 실시하였다. TDR 신호를 이용하여 흙의 유전상수, 전기전도도, 특성상수 값을 도출하였다. 이를 통해 흙의 함수비 및 건조밀도를 구하였고, 실제 측정한 값과의 비교를 통하여 개발 TDR의 적용성을 검토하였다. 실험 결과, 건조밀도의 경우 평균적으로 약 2%의 오차를 보이며, 함수비의 경우 평균적으로 약 0.5%의 오차를 보이는 것을 확인할 수 있었다. 실험 결과를 통하여 기존의 TDR시스템을 사용하였을 때 발생할 수 있는 문제점과 측정할 때 소요되는 시간 등을 줄일 수 있을 것으로 판단된다.

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Information
  • Publisher :The Korean Geotechnical Society
  • Publisher(Ko) :한국지반공학회
  • Journal Title :Journal of the Korean Geotechnical Society
  • Journal Title(Ko) :한국지반공학회 논문집
  • Volume : 32
  • No :4
  • Pages :51-61
  • Received Date : 2016-03-14
  • Revised Date : 2016-03-26
  • Accepted Date : 2016-03-28
  • DOI :https://doi.org/10.7843/kgs.2016.32.4.51
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