한국건설순환자원학회논문집 (Journal of the Korean Recycled Construction Resources Institute)

한국건설순환자원학회 (Korean Recycled Construction Resources Institute)
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균열 아크릴 시편의 기체 확산계수와 균열폭의 관계

Relationship between Crack Width and Gas Diffusion Coefficient of Cracked Acrylic Specimens

  • Lee, Do-Keun (Department of Civil Engineering, Chung-nam University) ;
  • Lim, Min-Hyuk (Department of Civil Engineering, Chung-nam University) ;
  • Shin, Kyung-Jun (Department of Civil Engineering, Chung-nam University)
  • 투고 : 2018.09.27
  • 심사 : 2018.11.14
  • 발행 : 2018.12.30
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초록

최근 구조물의 유지관리의 중요성이 부각되면서 자기치유 콘크리트 기술 분야의 연구가 활발히 이루어지고 있다. 이에 반해서 자기치유 성능을 평가하기 위한 척도는 부족한 실정이다. 균열폭을 측정하기 위한 방법으로 시각적인 방법이 1차적으로 사용되고 있으나 시편 내부의 균열폭을 관찰하기가 어려우며, 비균질한 균열특성으로 인해 표면에 대한 국부적인 측정만 할 수 있는 단점이 있다. 균열에 대한 간접적인 평가 방법으로 투수실험이 널리 활용되고 있지만 물의 점성으로 인한 문제가 있으며, 또한 실험 중 시편내부 물질의 용출될 가능성이 존재한다. 본 연구에서는 기체확산 특성을 활용한 균열폭 평가 방법을 제안하고자 하였다. 아크릴로 이상화된 직선균열을 제작하여 균열폭, 두께에 따른 시편의 확산계수를 분석하였다. 실험결과를 통하여 균열폭과 확산계수는 선형관계에 있음을 보였고, 두께와 확산계수는 역수의 관계에 있음을 증명하였다.

Recently, as the importance of structural maintenance has been increased, studies on self - healing concrete technology are being actively carried out. On the other hand, test for evaluating the self-healing performance is not standardized yet. Although visual test is used as a basic method for measuring crack widths, it is difficult to observe the crack width inside the specimen, and there is a disadvantage that only the local measurement of the surface can be measured due to the inhomogeneous cracking characteristics. Although permeability test has been widely used as an indirect method for measuring crack width, there is a problem due to the viscosity of water, and also a possibility that the internal material of the specimen may be eluted during the test. In this study, we propose a crack width evaluation method using gas diffusion characteristics. Idealized straight cracks were fabricated by acrylic and the diffusion coefficients of specimens were analyzed with respect to crack width and thickness. The experimental results show that the crack width and the diffusion coefficient are in a linear relationship and that the thickness and diffusion coefficient are inversely related.

키워드

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Fig. 1. Oxygen permeability test of none cracking specimen

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Fig. 2. Experiment device

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Fig. 3. Measuring device for oxygen gas concentration

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Fig. 4. Oxygen concentration change of C series with respect to measuring time

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Fig. 5. Relationship between diffusion coefficient and crack width for C series specimens

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Fig. 6. Relationship between diffusion coefficient and specimen thickness for T series specimens

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Fig. 7. Oxygen inflow of T series specimens

Table 1. Specimen information

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Table 2. Diffusion coefficient of C series specimens

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Table 3. Oxygen Inflow through a crack for T series specimens

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참고문헌

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