Journal of the Korea Institute of Building Construction (한국건축시공학회지)

The Korean Institute of Building Construction (한국건축시공학회)
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Strategies for Reducing Setting Time Delays in Thixotropic Cement-Based Materials

요변성을 부여한 시멘트 계열 재료에서 발생한 응결 지연 저감 방안

  • Kim, In-Tae (Department of Architectural Engineering, Gyeongsang National University) ;
  • Lim, Young-Ju (Department of Architectural Engineering, Gyeongsang National University) ;
  • Lee, Kang-Hyeok (Department of Architectural Engineering, Gyeongsang National University) ;
  • Lee, Yu-Jeong (Department of Architectural Engineering, Gyeongsang National University) ;
  • Han, Dong-Yeop (Department of Architectural Engineering, Gyeongsang National University)
  • Received : 2024.06.14
  • Accepted : 2024.09.24
  • Published : 2024.10.20
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Abstract

This research explores a refined approach to mitigating the setting time delays encountered in thixotropic cement-based materials. The study evaluated three alkali agents-potassium hydroxide, sodium hydroxide, and calcium hydroxide-along with a chemical accelerator, to determine their effectiveness in addressing the delay. The results revealed that, aside from calcium hydroxide, the alkalis and the accelerator showed promising outcomes in reducing setting time. However, increasing the dosages of potassium hydroxide and sodium hydroxide negatively impacted the thixotropic properties of the paste. In contrast, the accelerator demonstrated a unique ability to preserve and even enhance thixotropy with higher dosages. Therefore, the findings suggest that the accelerator is a more effective and reliable solution than alkali materials for resolving setting time delays in thixotropic cement systems

본 연구의 목적은 고요변성이 발현된 시멘트 계열 재료에서 발생한 응결 지연을 극복하는 것이다. 본 연구에서는 응결 지연을 극복하기 위해 사용된 재료는 알칼리 계열 재료인 수산화칼륨, 수산화나트륨, 수산화칼슘 3가지와 급결제를 사용하여 응결 지연 극복에 효과가 있는지 연구를 진행하였다. 연구 결과 수산화칼륨, 수산화나트륨, 급결제의 경우 응결 지연 극복에 효과가 있는 것을 확인하였다. 수산화칼륨과 수산화나트륨은 첨가량에 따라 Plain 수준으로 응결을 회복하였지만, 오히려 요변성을 감소하였다. 급결제의 경우 첨가량이 증가함에 따라 요변성 또한 증가하는 것을 확인하였다. 이에 시멘트 계열 재료에서 발생한 응결 지연 극복은 알칼리 계열 재료보다 급결제가 적합한 것으로 판단된다.

Keywords

Acknowledgement

This research was supported by Basic Science Research Program through the National Research Foundation of Korea(NRF) funded by the Ministry of Science, ICT & Future Planning(2021R1C1C110101461461382116530104). This results was supported by "Regional innovation Strategy(RIS)" through the Natinal Research Foundation of Korea(NRF) funded by the Ministry of Education(MOE)(2021RIS-003).

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