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Evaluation of Mechanical and Durability Performance of Mortar Shotcrete

모르타르 숏크리트의 역학성능 및 내구성능 평가

  • 박병선 (한국건설생활환경시험연구원 건설기술연구센터) ;
  • 장건영 (한국건설생활환경시험연구원 건설기술연구센터) ;
  • 최영철 (가천대학교 토목환경공학과)
  • Received : 2019.07.03
  • Accepted : 2019.08.29
  • Published : 2019.09.01

Abstract

In this study, the mechanical property and durability of improved bond performance mortar shotcrete was investigated. Mortar shotcrete was prepared by replacing coarse aggregate with 100% fine aggregate in the shotcrete mixture proportion proposed in the road construction standard specification. OPC, GGBFS and anhydrite were used as binders, and polymer powder was substituted for 1% and 2% of binder for improving bond property. From the experimental results, it was found that the compressive strength decreased with increasing polymer addition, but the bond strength increased. The addition of polymer to mortar shotcrete also reduced the drying shrinkage and improved the resistance to carbonation. Initial hydration heat of mortar shotcrete decreased with the addition of polymer, and it was judged that the initial compressive strength decreased.

본 연구에서는 부착성능 향상 모르타르 숏크리트의 역학적 특성 및 내구성능에 대한 실험적 연구를 수행하였다. 모르타르 숏크리트는 도로공사 표준시방서에서 제시하고 있는 숏크리트 배합에서 굵은 골재를 100% 잔골재로 치환한 배합을 이용하였다. 바인더로는 OPC와 GGBFS, 무수석고를 이용하였으며, 폴리머는 바인더의 각각 1, 2% 치환하여 사용하였다. 실험을 통해 폴리머를 사용하는 경우 압축강도가 감소하나 부착강도는 Plain 대비 50% 정도 향상되는 것을 확인하였다. 또한 폴리머 혼입 시 건조수축이 감소하고 탄산화 저항성도 향상되었다. 반면 초기 수화 반응에 의한 발열량은 감소하였는데, 이로 인해 초기 압축 강도가 감소한 것으로 판단된다.

Keywords

References

  1. Ministry of Land, Infrastructure and Transport. (2019). Road Bridge and Tunnel Status Information System, https://bti.kict.re.kr/bti/
  2. Ohama, Y. (1987), Principle of latex modification and some typical properties of latex-modified mortars and concretes. ACI Materials Journal., 84(6), 511-518.
  3. Meishan, P., Yue, W.U., Kim, K.I., Hyung, W.G., Soh, Y.S. (2004), Effect of the Monomer Ratio on the Properties of Poly(methyl methacrylate butyl acrylate) Latex-Modified Mortars, Journal of Applied Polymer Science., 93, 2403-2409. https://doi.org/10.1002/app.20744
  4. Afridi, M.U.K., Ohama, Y., Demura, K., Iqbal, M.Z. (2003), Development of polymer films by the coalescence of polymer particles in powdered and aqueous polymer-modified mortars, Cement and Concrete Research., 33(11), 1715-1721. https://doi.org/10.1016/S0008-8846(02)01094-3
  5. Kim, W.K. (2006), Strength and Adhesion Properties of Polymer-Modified Mortars using Redispersible Powders and Polymer Dispersions, Journal of the Architectural Institute of Korea., 22(4), 119-126 [in Korean].
  6. Song, H. Shin, H.U. (2018), High Temperature Properties of Cement Mortar Using EVA, EVCL Redispersible Polymer Powder and Fly Ash, Journal of the Korea Recycled Construction Resources Institute., 6(4), 365-372 [in Korean]. https://doi.org/10.14190/JRCR.2018.6.4.365
  7. KS L ISO 679. (2016), Methods of Testing Cements-Determination of Strength, Korea [in Korean].
  8. KS F 2762. (2016), Standard Test Method for the Bond Strength of Concrete Repair and Overlay Materials by Pull-Off Method, Korea [in Korean].
  9. KS F 2424. (2015), Standard Test Method for Length Change of Mortar and Concrete, Korea [in Korean].
  10. KS F 2584. (2010), Standard Test Method for Accelerated Carbonation of Concrete, Korea [in Korean].
  11. Shariq, M., Prasad, J., Abbas, H. (2016), Creep and drying shrinkage of concrete containing GGBFS, Cement and Concrete Composites., 68, 35-45. https://doi.org/10.1016/j.cemconcomp.2016.02.004
  12. Kim, D.Y., Cho, H.K., Lee, H.S. (2014), Effects of the Reaction Degree of Ground Granulated Blast Furnace Slag on the Properties of Cement Paste, Journal of the Korea Concrete Institute., 26(6), 723-730 [in Korean]. https://doi.org/10.4334/JKCI.2014.26.6.723
  13. Sanjuana, M.A., Estevezb, E., Argizc, C., Barriob, D. (2018), Effect of curing time on granulated blast-furnace slag cement mortars carbonation, Cement and Concrete Composites., 90, 257-265. https://doi.org/10.1016/j.cemconcomp.2018.04.006

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  1. 숏크리트용 섬유 그물망 일체형 터널 지보시스템의 지보 성능 평가 vol.8, pp.4, 2020, https://doi.org/10.14190/jrcr.2020.8.4.545