Journal of the Korean Geosynthetics Society (한국지반신소재학회논문집)

Korean Geosynthetics Society (한국지반신소재학회)
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Analysis of Water Penetration through Pores in Spray-applied Waterproofing Membrane Using X-ray CT Images

X-ray CT를 이용한 분무식 방수 멤브레인의 공극 내 물 침투 분석

  • Choi, Soon-Wook (Geotechnical Engineering Research Institute, Korea Institute of Civil Engineering and Building Technology) ;
  • Kang, Tae-Ho (Geotechnical Engineering Research Institute, Korea Institute of Civil Engineering and Building Technology) ;
  • Chang, Soo-Ho (Geotechnical Engineering Research Institute, Korea Institute of Civil Engineering and Building Technology) ;
  • Lee, Chulho (Geotechnical Engineering Research Institute, Korea Institute of Civil Engineering and Building Technology) ;
  • Choi, Myung-Sik (Silkroad T&D Co., Ltd) ;
  • Kim, Kwang Yeom (Geotechnical Engineering Research Institute, Korea Institute of Civil Engineering and Building Technology)
  • Received : 2017.12.11
  • Accepted : 2017.12.26
  • Published : 2017.12.30
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Abstract

The spray-applied waterproofing membrane is installed on shotcrete or concrete surface to make impermeable layer with 3-5 mm thick for the purpose of waterproofing. This study aims to determine the internal structure of a spray-applied waterproofing membrane including pores by using X-ray CT technique. Before obtaining X-ray images of the membrane specimens, a waterproof performance test was performed on the membrane specimens with a water pressure of 500 kPa for 28 days. Results show that the movement of moisture is made through micropores. This is based on the fact that the large pores inside the membrane are not saturated and the degrees of saturation of the micropores are high. X-ray image is effective for determining the pore size distribution and whether the membrane with pores contains the water However, it is necessary to pay attention to the determination of water content, since water content may vary depending on the threshold value of X-ray image analysis applied to calculate the water content.

분무식 방수 멤브레인은 3-5mm 두께로 숏크리트 또는 콘크리트 면에 타설하여 불투수층을 형성시킴으로써 방수효과를 나타낸다. 본 연구는 공극을 포함하는 분무식 방수 멤브레인을 조사하기 위하여 X-ray CT기술을 이용하여 내부구조를 파악하였다. 분무식 방수 멤브레인의 X-ray이미지를 얻기 전에 28일 동안 500kPa의 수압을 작용시키는 방수성능시험을 수행하였고 물이 침투되어있는 멤브레인 시편에 대해 X-ray CT를 실시하였다. 그 결과, 멤브레인 내부의 큰 공극들이 포화되어 있지 않은 점과 미세공극의 포화도가 높은 점을 볼 때, 수분의 이동이 미세공극을 통해 이루어지는 것으로 예상할 수 있었다. 또한 X-ray 이미지는 멤브레인 내부의 공극 크기 및 분포와 함수여부를 판단하는데 효과적임을 알 수 있었으나, 함수량을 계산하기 위해 적용하는 임계값에 따라 함수율의 차이가 발생할 수 있으므로 이에 대한 주의가 필요하다.

Keywords

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