DOI QR코드

DOI QR Code

Strength Development of the Concrete Incorporating Blast Furnace Slag and Recycled Aggregate as Alkali Activator

고로슬래그 미분말과 알칼리 자극재로서 순환골재를 사용하는 콘크리트의 강도발현 특성

  • Kim, Jun-Ho (Dept. of Architectural Engineering, Cheong-ju Univ.) ;
  • Han, Min-Cheol (Eng., Dept. of Architectural Engineering, Cheong-ju Univ.) ;
  • Han, Cheon-Goo (Eng., Dept. of Architectural Engineering, Cheong-ju Univ.)
  • Received : 2014.05.01
  • Accepted : 2014.06.24
  • Published : 2014.06.30

Abstract

The objective of this study is to evaluate the strength development of blast furnace slag concrete in response to the use of recycled aggregate as alkali activator. The influence of the amount of recycled aggregate was evaluated depending on different ratios of replacement for each RFA and RCA to NFA and NCA, respectively. The results indicated that as replacement of RFA and RCA increased, their strength exhibited to be increased. This was due to the fact that the latent hydraulic properties of blast furnace slag was activated by the alkali in recycled aggregates. However, in case of 365-days, it showed lower compressive strength than using NA(natural aggregates) which could be explained as the exhaustively use of alkali containing in RA. The specimens using RA showed about 90% of compressive strength comparing with specimens using NA.

본 연구에서는 자원순환형으로 재활용되는 순환골재(RA)를 고로슬래그 미분말(BS) 콘크크리트에 치환하여 강도발현특성을 확인하므로 RA의 실용화에 기여하고자하는 연구이다. 즉, BS치환 콘크리트에 RA를 순환잔골재(RFA) 순환굵은골재(RCA)로 나누어 천연잔골재(NFA) 천연굵은골재(NCA)에 치환율을 실험변수로 하여 실시하였다. 실험결과 RFA RCA의 치환율이 증가함에 따라 강도가 증가하는 것을 확인하였는데, 이는 RA의 미수화 시멘트에 의한 알칼리자극재(Alkali Activation) 역할을 하여 BS의 불투수성 피막을 파괴하여 잠재수경성 반응을 촉진시킨 것으로 판단된다. 그러나, 재령 365일에서는 RA의 알칼리가 거의 소비되어 효과를 발휘하지 못하고, 또한 RA의 낮은 품질특성에 기인하여 강도가 다소 저하하나, 천연골재(NA)만을 사용한 시험체에 비해 약 90 % 전후의 강도를 나타내어 다소 양호한 값이며, BS의 치환할 경우 오히려 NA 시험체보다 높은 강도를 나타내어 우려할 사항은 아닌 것으로 분석되었다.

Keywords

References

  1. Han, C.G., Son, S.H., Park, K.T. (2011). Effect of Recycled Aggregates Powder on the Properties of Zero Cement Mortar Using the Recycled Fine Aggregates and Fly-Ash, Architectural Institute of Korea. 27(6), 99-106.
  2. Han, M.C., Lee, H.J., Han, C.G. (2013). Effect of Fine Particle Cement and Recycled Aggregates as Alkali Activator on the Engineering Properties and Micro-Structure of High Volume Blast Furnace Slag Concrete, Journal of the Korea Institute of Building Construction. 13(6), 602-608. https://doi.org/10.5345/JKIBC.2013.13.6.602
  3. Lee, D.H.(2004). Problem and Countermeasure of Recycled Aggregates for Concrete, Korean national housing corporation. Housing and Urban. 83, 29-35.
  4. Nam, S.I., (1995). A Study on the Engineering Properties of Resysled Aggregate Concrete, Ph.D thesis, Chungnam National University, Korea.
  5. Sim, J.S., Park, C.W., Park, S.J., Kim, Y.J. (2006). Characterization of Compressive Strength and Elastic Modulus of Recycled Aggregate Concrete with Respect to Replacement Ratios, Korean Society of Civil Engineers. 26(1), 213-218.
  6. Son, S.H., (2011). Development of Zero-Cement Mortar Using Reactivity of Recycled Fine Aggregates and Mineral Admixtures, Ph.D thesis, Chongju University, Korea.
  7. Yang, K.H., Song, J.K., Lee, K.S., and Ashour, A. F.(2009) Flow and Compressive Strength of Alkali-Activated Mortars, ACI Material Journal, 106(1), 50-58.

Cited by

  1. Crushing Characteristics of Single Particle of Recycled Aggregate from Waste Concrete vol.32, pp.12, 2016, https://doi.org/10.7843/kgs.2016.32.12.23