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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

Soon-Wook Choi1
,
Tae-Ho Kang2*
,
Soo-Ho Chang3
,
Chulho Lee4
,
Myung-Sik Choi5
,
Kwang Yeom Kim6
최 순욱1
,
강 태호2*
,
장 수호3
,
이 철호4
,
최 명식5
,
김 광염6
1Member, Research Specialist, Geotechnical Engineering Research Institute, Korea Institute of Civil Engineering and Building Technology
2Member, Budding Researcher, Geotechnical Engineering Research Institute, Korea Institute of Civil Engineering and Building Technology
3Nonmember, Senior Research Fellow, Geotechnical Engineering Research Institute, Korea Institute of Civil Engineering and Building Technology
4Member, Research Specialist, Geotechnical Engineering Research Institute, Korea Institute of Civil Engineering and Building Technology
5Nonmember, Executive Engineer, Silkroad T&D Co.
6Nonmember, Research Fellow, Geotechnical Engineering Research Institute, Korea Institute of Civil Engineering and Building Techn
*교신저자. *Corresponding Author. 
30 December 2017. pp. 212-219
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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.

Keywords
Spray-appied membrane
CT
X-ray
Pore
Water content

분무식 방수 멤브레인은 3-5mm 두께로 숏크리트 또는 콘크리트 면에 타설하여 불투수층을 형성시킴으로써 방수효과를 나타 낸다. 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.

References
1
Bradley, D., and Roth, G. (2007), “Adaptive thresholding using the integral image”, Journal of Graphics Tools, Vol.12, No.2, pp.13-21.
2
Chae, D., Lee, J., Kim, K.-Y. and Cho, W. (2017), “Particle Spacing Analysis of Frozen Sand Specimens with Various Fine Contents by Micro X-ray Computed Tomography Scanning”, Journal of the Korean Geo-Environmental Society, Vol.18, No.1, pp.31-35.
3
Chang, S.-H, Choi, S.-W., Lee, C., Kang, T.-H., Hwang, G.-S., Kim, J. and Choi, M.-S. (2016), “Development and Performance Evaluation of a Two-component Thin Spray-on Liner to Guarantee Its Homogeneous Qualities and to Reduce Dust”, TUNNEL & UNDERGROUND SPACE, Vol.26 No.5, pp.441-453.
4
Choi, S.-W., Kang, T.-H., Chang, S.-H., Lee, C., Kim, J. and Choi, M.-S. (2017), “A preliminary study of watertightness and salt water resistance of spray-applied membrane”, J. of Korean Tunn. Undergr. Sp. Assoc., Vol.19, No.2, pp.283-299.
5
Choo, M.K., Song, I.S., Lee, H.K., Kim, T.H., and Chang, C.D. (2011), “Application of the electrical impedance of rocks in characterizing pore geometry”, The Journal of Engineering Geology, Vol.21, No.4, pp.323-336(in Korea with English abstract).
6
Chung, S-Y., Kim, Y-J., Yun, T.S. and Jeon, H-G., (2011), “Evaluation of Void Distribution on Lightweight Aggregate Concrete Using Micro CT Image Processing”, Journal of the Korean Society of Civil Engineers, Vol.31, No.2A, pp. 121-127.
7
David, C. and Darot, M., (1993), “Pore structures and transport properties of sandstone”, Transport in porous media, Vol.11, pp.161-177.
8
Grattoni, C.A. and Dawe, R.A., (1995), “Anisotropy in pore structure of porous media”, Powder Technology, Vol.85, pp. 143-151.
9
Holter, K.G. and Geving, S. (2016), “Moisture Transport Through Sprayed Concrete Tunnel Linings”, Rock Mech. Rock Eng., Vol.49, pp.243-272.
10
Keller, A. (1998), “High resolution, non-destructive measurement and characterization of fracture apertures”, International Journal of Rock Mechanics and Mining Sciences, Vol.35, No.8, pp.1037-1050.
11
Kim, K.-Y. and Kim K.M. (2014), “Evaluation of Pore Size Distribution of Berea Sandstone using X-ray Computed Tom-ography”, The Journal of Engineering Geology, Vol.24, No.3, pp.353-362.
12
Louis, L., David, C. and Robion, P. (2003), “Comparison of the anisotropic behaviour of undeformed sandstones under dry and saturated conditions”, Tectonophysics, Vol.370, pp. 193-212.
13
Montemagno, C.D. and Pyrak-Nolte, L.J. (1999), “Fracture network versus single fractures: measurement of fracture geometry with X-ray tomography”, Physics and Chemistry of the Earth, Part A: Solid Earth and Geodesy, Vol.24, No.7, pp.575-579.
14
Taud, H., Martinez-Angeles, R., Parrot, J.F., and  Hernandez- Escobedo, L. (2005), “Porosity estimation method by X-ray computed tomography”, Journal of petroleum science and engineering, Vol.47, No.3, pp.209-217.
15
DIN 1048 (1991), German Standard for determination of Permeability of Concrete, Part-5.
16
EFNARC (2008), Specification and Guidelines on Thin Spray-on Liners for Mining and Tunnelling.
17
EN 1928 (2000), Flexible sheets for waterproofing. Bitumen, plastic and rubber sheets for roof waterproofing. Determination of watertightness.
18
EN 12390-1 (2012), Testing hardened concrete. Part 1: Shape, dimensions and other requirements for specimens and moulds.
19
EN 12390-8 (2009), Testing hardened concrete. Part 8: Depth of penetration of water under pressure.
20
EN 14891 (2006), Liquid applied water impermeable products for use beneath ceramic tiling bonded with adhesives- Requirements, test methods, evaluation of conformity, classification and designation.
21
ITA (2013), ITAtech Design guidance for spray applied waterproofing membranes. ITAtech Activity Group Lining and Waterproofing.
22
KSRM (2006), Standard test method for porosity and density of rock.
23
MOLIT (2010), Road design manual - Part 6: Tunnel, Ministry of Land, Infrastructure and Transport, pp.608-8~9.
24
MOLIT (2007), Tunnel design guideline, Ministry of Land, Infrastructure and Transport, p.69.
Information
  • Publisher :Korean Geosythetics Society
  • Publisher(Ko) :한국지반신소재학회
  • Journal Title :Journal of the Korean Geosynthetics Society
  • Journal Title(Ko) :한국지반신소재학회 논문집
  • Volume : 16
  • No :4
  • Pages :212-219
  • Received Date : 2017-12-12
  • Revised Date : 2017-12-19
  • Accepted Date : 2017-12-26
  • DOI :https://doi.org/10.12814/jkgss.2017.16.4.211
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