This research is to reduce the formwork leakage of high-fluidity concrete caused by insufficient accuracy of formwork fabrication widely used for high-fluidity concrete to general strength concrete. However, in the actual construction site, because of the insufficient accuracy of formwork fabrication may cause leaking concrete of mortar through a gab of the formwork. Therefore, in this research, which builds on previous research into providing thixotropy with PVA and Borax, the use of thixotropy to reduce high-fluidity mortar leakage was evaluated. The results of the experiment proved that the use of thixotropy with PVA and Borax can contribute to reduction of the formwork leakage of high-fluidity mortar. This finding is expected to lead to further research on reducing leakage of high-fluidity concrete.
본 연구의 목적은 고유동 콘크리트의 활용범위를 증진시키기 위하여 거푸집 정밀도 부족에 따른 고유동 콘크리트의 누출을 방지 혹은 저감하는 것이다. 일반강도 콘크리트에 고유동성이 부여되는 경우 거푸집의 정밀도가 낮으면 거푸집 틈새로 콘크리트 누출이 우려되는바 일반적인 현장에서 유동성이 높은 일반강도 콘크리트의 적용에 지장이 있다. 이에 본 연구는 이전 연구결과에서 얻어진 PVA와 붕사를 사용한 고요변성 부여하는 방법을 이용하여 고유동 콘크리트에 요변성을 부여하여 거푸집의 누출을 저감하고자 연구를 수행하였다. 연구결과를 통해 PVA와 붕사가 고유동 모르타르 조건에서 거푸집 누출 저감에 기여한다는 것을 증명하였다. 이를 통해 고유동 콘크리트의 거푸집 누출량 저감 연구의 시작점이 될 것으로 기대한다.
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(2021R1C1C11010146).
References
Kang BH. The present status on mix design construction technology of high-fluidity concrete. Magazine of the Korea Concrete Institute. 2001 May;13(2):86-90.https://doi.org/10.22636/MKCI.2001.13.2.86
Han CG, Oh SY, Kim KC. A study on the development of separation-reduced fluidized concrete using thickener. Korea Ready Mixed Concretea Industry Association. 2001 Apr;67(4):6-16.
Gregori A, Ferron RP, Sun Z, Shah SP. Experimental simulation of self-consolidating concrete formwork pressure. ACI Materials Journal. 2008 May;105(1):97-104.
Lee HS, Lee YJ, Lee YJ, Han D. Fundamental properties analysis for thixotropic cement-based materials using pva and borax. Journal of the Korea Institute of Building Construction. 2020 Jun;20(3):213-21. https://doi.org/10.5345/JKIBC.2020.20.3.213
Ferron RP, Gregori A, Sun Z, Shah SP. Rheological method to evaluate structural buildup in self-consolidating concrete cement pastes. ACI Materials journal. 2007 May;104(3):242-250.