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Initial Behavior and Shrinkage Properties of Lime Mortars for Restoration of Cultural Heritage According to the Mixing Ratio

석회 종류와 배합비 별 문화재 보수용 석회 모르타르의 초기거동특성과 수축특성 연구

  • Nam, Byeong Jik (Restoration Technology Division, National Research Institute of Cultural Heritage) ;
  • Noh, Sang Kyun (Construction Division, Korea Conformity Laboratories) ;
  • Kim, Eun Kyung (Restoration Technology Division, National Research Institute of Cultural Heritage) ;
  • Ahn, Sun Ah (Restoration Technology Division, National Research Institute of Cultural Heritage) ;
  • Kang, So Yeong (Restoration Technology Division, National Research Institute of Cultural Heritage)
  • 남병직 (국립문화재연구소 복원기술연구실) ;
  • 노상균 (한국건설생활환경시험연구원 건설본부) ;
  • 김은경 (국립문화재연구소 복원기술연구실) ;
  • 안선아 (국립문화재연구소 복원기술연구실) ;
  • 강소영 (국립문화재연구소 복원기술연구실)
  • Received : 2020.10.15
  • Accepted : 2020.11.12
  • Published : 2020.12.29

Abstract

This study investigated the initial behavior (flowability and setting properties) and shrinkage characteristics of lime mortar, based on the mixing ratio of hydrated lime (lump, powder) and commercial lime, which is primarily used for repairing and restoring cultural assets. The flowability showed that the optimum mixing water contents of the masonry lime mortar were 8-10% for the lump hydrated lime, 10-18% for the powdered hydrated lime, and 17-40% for the commercial hydrated lime. The results of the setting and shrinkage analysis showed that the average final setting time ratio compared to the standard of cultural asset repair was in the increasing order of commercial hydrated lime(0.4) < powder hydrated lime(5.6) < lump hydrated lime(5.7). Moreover, the average shrinkage ratio was ordered as lump hydrated lime(1.1) < powder hydrated lime(1.2) < commercial hydrated lime(3.0). The analysis of the physical and chemical characteristics of hydrated lime showed that the optimum mixing water content was reduced as the particle size of the lime increased, thus delaying the setting time and decreasing the length change rate (shrinkage). These results are expected to contribute to the prediction of the initial behavior and shrinkage characteristics of mortars using handmade and commercial lime during repair and restoration work on cultural, heritage buildings.

본 연구는 문화재 보수에 사용되는 소괴 소석회, 분말 소석회, 시판 소석회를 대상으로 배합비에 따른 석회 모르타르의 유동성, 응결시간 및 수축율을 비교하였다. 유동성 시험 결과, 문화재 조적용 석회 모르타르의 최적 배합수 비율은 소괴 소석회 8~10%, 분말 소석회 10~18%, 시판 소석회 17~40%의 범위로 나타났다. 응결시간과 수축율 분석 결과, 문화재수리표준품셈에 기술된 전돌벽쌓기(습식) 대비 종결시간비는 시판 소석회(0.4) < 분말 소석회(5.6) < 소괴 소석회(5.7)의 순으로, 수축율비는 소괴 소석회(1.1) < 분말 소석회(1.2) < 시판 소석회(3.0)의 순으로 나타났다. 물리·화학적 특성 분석 결과, 소석회의 입자크기가 커질수록 최적 배합수 함량은 낮아졌고 응결시간은 지연되며 수축율은 감소하였다. 이와 같은 결과는 향후 건축문화재의 수리·복원 현장에 사용되는 석회 모르타르의 초기거동과 수축특성을 예측하는데 기여할 것으로 판단된다.

Keywords

Acknowledgement

본 연구는 문화재청 국립문화재연구소 문화유산조사연구(R&D) 사업의 지원을 받아 이루어졌으며, 이에 깊이 감사드린다.

References

  1. Ahn, S.A., Kim, E.K., Nam, B.J., Hlaing, C.S.S. and Kang, S.Y., 2018, Mineralogical and physical properties of lime plaster used in wall repair in temple of Bagan, Myanmar. J. Miner. Soc. Korea, 31(4), 267-275. (in Korean with English abstract) https://doi.org/10.9727/jmsk.2018.31.4.267
  2. ASTM, 2016, ASTM C109/C109M:16a Standard test method for compressive strength of hydraulic cement mortars (using 2-in. or [50-mm] cube specimens).
  3. Carran, D., Hughes, J., Leslie, A. and Kennedy, C., 2012, The effect of calcination time upon the slaking properties of quicklime. RILEM bookseries-Historic mortars, 7, 283-295.
  4. Elert, K., Rodriguez-Navarro, C., Pardo, E.S., Hansen, E. and Cazalla, O., 2002, Lime mortars for the conservation of historic buildings. Studies in Conservation, 47, 62-75.
  5. Hwang, H.Z. and Kang, N.Y., 2010, Preliminary study on traditional earth construction technique use of lime. Journal of the KIEAE, 10(2), 3-8. (in Korean with English abstract)
  6. Kang, S.H., Hwang, J.K. and Kwon, Y.H., 2019a, Effects of amount of slaking water on physical and chemical properties of handmade hydrated lime used for preservation of architectural heritage. Journal of the Architectural Institute of Korea Structure & Construction, 35(2), 21-28. (in Korean with English abstract) https://doi.org/10.5659/JAIK_SC.2019.35.2.21
  7. Kang, S.H., Hwang, J.K. and Kwon, Y.H., 2019b, Carbonation reaction and strength development of air lime mortar with superplasticizer. Journal of the Architectural Institute of Korea Structure & Construction, 35(7), 179-186. (in Korean with English abstract) https://doi.org/10.5659/JAIK_SC.2019.35.7.179
  8. Kim, E.K., Ahn, S.A., Nam, B.J. and Kang, S.Y., 2018, A comparative study of outer castle pointing and modern pointing in Namhansanseong yeojang. KOMUNHWA, 92, 61-77. (in Korean with English abstract)
  9. Kim, J.H., No, H.S. and Seo, S.S., 2006, Introduction of hydraulic lime mortar as eco-friendly architecture material. Ceramist, 9(3). (in Korean).
  10. Kim, T.N., 2002, Myung Dong cathedral church mortar 1th report. (in Korean with English abstract)
  11. Kim, T.N., 2004, Mortar and brick analysis of Yongsan seminary and Winhyoro cathedral church. (in Korean with English abstract)
  12. Lanas, J. and Alvarez, J.I., 2004, Dolomitic limes: evolution of the slaking process under different conditions. Thermochimica Acta, 423, 1-12. https://doi.org/10.1016/j.tca.2004.04.016
  13. Noh, S.K. and Han, C.G., 2012, Effects of cement fineness modulus (CFM) on the fundamental properties of concrete. Journal of the Korea Institute of Building Construction, 12(3), 284-290. (in Korean with English abstract) https://doi.org/10.5345/JKIBC.2012.12.3.284
  14. Park, C.W., Lim, N.G. and Lee, K.Y., 2014, A Research study on fundamental properties of traditional oil compound lime as eco-friendly building material. Journal of the Architectural Institute of Korea, 30(7), 47-54. (in Korean with English abstract)
  15. Ministry of Land, Infrastructure and Transport, 2017, Building structure standards.
  16. Cultural Heritage Administration, 2019, Cultural property repair standard product count.
  17. KS, 2015, KS F 2424 Standard test method for length change of mortar and concrete.
  18. KS, 2017, KS L 5105 Testing method for compressive strength of hydraulic cement mortars.
  19. KS, 2017, KS L 5111 Flow table for use in tests of hydraulic cement.
  20. KS, 2018, KS L 5220 Dry ready mixed cement mortar.
  21. KS, 2016, KS L ISO 679 Methods of testing cements - Determination of strength.
  22. KS, 2014, KS L ISO 9597 Determination of setting time and soundness of cements.