• 레미콘
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• no.7 s.48
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• pp.41-45
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• 1996

• Journal of the Korean Society for Nondestructive Testing
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• v.20 no.4
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• pp.285-289
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• 2000

This study suggests a rebar detection technique for simultaneous detection of size and cover of embedded reinforcement in concrete. The structure of the probe made in this study is somewhat different from commercial ones. This probe has three sensing coils. Rebar size and cover depth can be evaluated by detecting and analyzing the signal from them. Amplitude and phase variation of each coil in the probe was investigated using an impedance analyzer and the loci of transfer functions of the coils were analyzed. The locus of transfer function from the sensing coil positioned inside excitation coil was simple as well known, but the others from the coils outside excitation coil were not so. Actual experiment on rebar detection was performed with our probe and an eddy current test system for various rebar sizes and depths. The signal shape according to variation of cover depths showed the same tendency with the transfer function loci acquired by impedance analyzer. The different variation pattern of signal enabled to evaluate rebar size and cover depth simultaneously.

• 한국터널공학회:학술대회논문집
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• 2005.04a
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• pp.202-212
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• 2005

배수식 방수방식으로 지하 30m에 건설된 NATM터널 통신구를 준공 7년후 완전방수식 방식으로 변경하였다. 터널 라이닝에 30m의 수압을 작용할 경우 발생하는 단면력을 구조검토하고 배근상태가 안전한가 분석하였다. 또한 라이닝의 시공단면을 확인하기 위하여 충격반향기법(Impact-Echo Method)탐사와 GPR탐사, 배근상태를 파악하기 위하여 철근탐지기를 사용하였다. 그 결과 30m 수압에 안전할 것이라는 판단하에 배면주입 방수공법을 적용 통신구를 완전방수 하였다. 그리고 배수식 통신구를 운용하는 비용과 완전방수공사비를 분석한 결과 배출되는 지하수량이 많은 경우 완전방수시공이 경제성이 있다고 분석되었다.