Journal of the Korean GEO-environmental Society (한국지반환경공학회 논문집)

Korean Geo-Environmental Society (한국지반환경공학회)
권호 표지
DOI QR코드

DOI QR Code

Compressive Behavior of Reinforced Nylon Fiber Slag-CB

나일론 섬유 보강 Slag-CB의 압축거동 특성

  • Younkyoung Lee (Dept. of Civil Engineering, Korea National University of Transportation) ;
  • Taeyeon Kim (Korea National University of Transportation) ;
  • Jongkyu Lee (Gwangik Co., Ltd.) ;
  • Youngsoo Joo (Dept. of Civil Engineering, Korea National University of Transportation) ;
  • Bongjik Lee (Dept. of Civil Engineering, Korea National University of Transportation)
  • Received : 2023.08.01
  • Accepted : 2023.09.25
  • Published : 2023.11.01
Download PDF
⟨ Previous Next ⟩

Abstract

Slag-CB is widely used in various fields that require groundwater control. It is a type of CB where a portion of the cement mixed with CB is replaced with GGBS. In general, Slag-CB has the advantage of long-term improvement in compressive strength, permeability, durability, and chemical resistance as the GGBS replacement ratio increases. However, there are problems such as decreased flexibility and resistance to deformation of the cut-off walls, as well as brittleness upon failure. To address these problems, some quality standards recommend designing Slag-CB with lower strength, which makes it challenging to apply high-strength Slag-CB with a high GGBS replacement ratio in the field.In this study, we aimed to improve the flexibility and resistance to deformation of Slag-CB to prevent brittle failure and improve the field applicability of Slag-CB. To achieve this, we evaluated the compressive behavior of nylon fiber-reinforced Slag-CB and proposed measures for enhancing the flexibility and resistance to deformation of Slag-CB.

지하수 제어가 필요한 분야에서 다방면으로 활용되는 Slag-CB는 CB의 일종으로 CB에 혼합되는 시멘트의 일부를 GGBS 로 치환하여 사용하는 차수벽의 일종이다. 일반적으로 Slag-CB는 GGBS의 치환율이 증가함에 따라 압축강도, 차수성, 내구성 및 내화학성 등이 장기적으로 향상되는 장점이 있으나, 벽체의 유연성 및 변형에 대한 저항성이 저하되며 파괴 시 취성을 보이는 문제가 있다. 이러한 문제를 해결하기 위해 일부 품질기준에서는 Slag-CB를 저강도로 설계하도록 권장하고 있어 GGBS 치환율이 높은 고강도의 Slag-CB의 현장 적용에 다소 어려움이 있다. 이에 본 연구에서는 Slag-CB의 유연성 및 변형에 대한 저항성을 개선하여 취성파괴를 방지함으로 Slag-CB의 현장 활용성 및 적용성을 향상시키기 위해 나일론 섬유를 혼합한 Slag-CB 차수벽을 대상으로 압축거동 특성을 평가하고, 이를 비교·분석함으로 Slag-CB의 유연성 및 변형에 대한 저항성을 향상시킬 수 있는 방안을 제시하였다.

Keywords

References

  1. Bureau of Reclamation (2014), "Chapter 16 : cutoff walls", U.S. Department of the Interior, Design Standards No. 13 Embankment Dams, pp. 35~40.
  2. Evans, J. C. and Dawson. A. R. (1999), Slurry walls for control of contaminant migration: A comparison of U.K. and U.S. practices", ASCE Specialty Conference on Geo-Engineering for Underground Facilities, ASCE Geotechnical Special Publication No. 90, Reston, Va., pp. 105~120.
  3. Han, C. G., Yoon, G. W., Han, M. C. and Shin, H. S. (2007), "A fundamental study on the nylon fiber concrete", Journal of the Architectural Institute of Korea Structure & Construction, Vol. 23, No. 4, pp. 95~102 (in Korean).
  4. Hwang, J. S., Kim, S. W., Jung, J. G., Lee, S. J., Oh, B. S. and Baek, S. C. (2016), Behavior characteristics of cement bentonite impervious walls related to mixing methods and curing time, Journal of the Korean Geo-Environmental Society, Vol. 17, No. 12, pp. 45~54 (in Korean). https://doi.org/10.14481/jkges.2016.17.12.45
  5. Jefferis, S. A. (1997), The origins of the slurry trench cut-off and a review of cement-bentonite cut-off walls in the UK", International containment technology conference and exhibition, 52~61. United States.
  6. Chowdhury, K., Kynett, M., Millet, R., Nixon, R., Walberg, F. and Tollefson, N. (2016), "The Use of Slag Cement in CB Seepage Cutoff Walls for Levees", 2016 Dam Safety Conference, pp. 1~17.
  7. Kim, D. G. and Lee, S. T. (2022b), "Mechanical properties and frost resistance of concrete with steel and nylon fibers", Journal of the Korean Recycled Construction Resources Institute, Vol. 10, No. 4, pp. 386~394 (in Korean).
  8. Kim, K. S., Kim, N. W., Lee, Y. W. and Bae, J. S. (1995), "The effects of fibers on the fracture toughness and strength of concrete", Journal of the Korean Society of Civil Engineers, Vol. 15, No. 1, pp. 83~96 (in Korean).
  9. Kim, T. Y. and Lee, B. J. (2022a), "Engineering properties of CB cut-off walls mixed with GGBS", Journal of the Korean Geo-Environmental Society, Vol. 23, No. 5, pp. 33~39 (in Korean).
  10. Kim, T. Y., Lee, B. J. and Hong, S. W. (2022), "Effect of curing temperature on the properties of ground granulated blast furnace slag-cement bentonite slurry", Geomechanics and Engineering, Vol. 29, No. 3, pp. 237~247. https://doi.org/10.12989/GAE.2022.29.3.237
  11. Opdyke, S. M. and Evans, J. C. (2005), Slag-cement-bentonite slurry walls, Journal of Geotechnical and Geoenvironmental Engineering, Vol. 131, No. 6, pp. 637~681.