DOI QR코드

DOI QR Code

Insulation Effect of Double Layered Bubble Sheet Application in Cold Weather Concrete and Initial Quality Control by Wireless Sensor Network

한중시공에서 2중 버블시트 포설에 따른 단열 효과분석 및 무선센서 네트워크에 의한 초기 품질관리

  • Han, Min-Cheol (Department of Architectural Engineering, Cheong ju University) ;
  • Seo, Hang-Goo (Department of Architectural Engineering, Cheong ju University)
  • Received : 2020.10.06
  • Accepted : 2020.12.23
  • Published : 2021.02.20

Abstract

The objective of this study is to evaluate the effect of the application of double layered bubble sheet on the curing of slab and wall concrete placed at the job site in cold weather and to offer a feasibility of Concrete IoT Management System(CIMS), which is wireless sensor network developed by the authors, to manage early age quality of the concrete in terms of temperature, maturity and strength development. Test results indicated that the application of bubble sheet enhances the insulation performance, which results in an increase of the temperature by around 1~20. 6℃. It is found that CIMS can gather the temperature, maturity and strength development data from the sensors embedded from 30 m far from CIMS successfully. Predicted compressive strengths by CIMS had good agreement with measured ones within 2 MPa error level until 7 days. It is thought that the combination of the bubble sheet application for cold weather protection and CIMS for quality management tool in cold weather concreting contributes to shorten the time for the form removal by one day.

본 연구는 한중 환경에서 가열 보온양생을 실시한 벽식구조 아파트의 슬래브 상부 및 벽체를 대상으로 2중 버블시트 포설에 따른 온도이력 및 강도발현 특성을 저자 등에 의해 이전 연구에서 개발된 무선센서 네트워크인 Concrete IoT Management System(CIMS)를 이용하여 실시간 모니터링 및 추정하고자 하였다. 분석결과 버블시트의 단열성능에 기인하여 구조체 콘크리트의 온도가 높게 나타났다. 또한, CIMS의 경우는 콘크리트 내부온도를 30 m까지 양호하게 무선센서 네트워크로 스마트폰에 전송되어 적산온도 및 실시간 압축강도 측정으로 효율적인 초기 품질관리가 가능할 수 있음을 알 수 있었다. 초기 품질관리 결과로서 압축강도는 7일 이내에서 약 2 MPa 이내의 오차로 추정될 수 있음에 따라 버블시트의 단열효과까지 포함하여 실무에서는 거푸집 존치기간을 1사이클 당 1일 정도 단축하는 공정관리 측면에서 효과도 얻을 수 있었다.

Keywords

References

  1. Koh KT, Park CJ, An GH, Ryu GS, Kim DG, Lee JH. Investigation on the minimum compressive strength to prevent early frost damage from the viewpoint of durability. Proceeding of Korea Concrete Institute; 2013May 11-13; Seoul (Korea). Seoul (Korea): Korea Concrete Institute; 2013. p. 87-8.
  2. Giatec Scientific Inc; Setting a New Standard for Concrete Testing Equipment [Internet]. Giatec: Ontario, Canada; 2020 Jan [updated 2021 Jan 1; cited 2021 Feb 10]. Available from: https://www.giatecscientific.com/.
  3. Lee JH, Kim MS, Moon BY, Lee SU, Han MC, Han CG. Influence on temperature of concrete by various kind of surface covered materials. Proceeding of Architectural Institute of Korea; 2017 Oct 17-18; Seoul (Korea). Seoul (Korea): Architectural Institute of Korea; 2017. p. 773-4.
  4. Lee YJ, Kim TW, Lee JJ, Lee SW, Han MC, Han CG. Strength monitoring by equivalent age method with wireless sensor network for concrete slab using insulated form work. Proceeding of Architectural Institute of Korea; 2018 Mar 21-22; Jeju (Korea). Seoul (Korea): Architectural Institute of Korea; 2018. p. 658-9.
  5. Lee YJ, Hyun SY, Kim TW, Lee SW, Han MC, Han CG. Strength monitoring of the wall concrete using insulation formwork and unreinforced formwork using maturity based wireless sensor network. Proceeding of Korea Concrete Institute; 2018 May 12-14; Kyungju (Korea). Seoul (Korea): Korea Concrete Institute; 2013. p. 325-6.
  6. Lee YJ, Hyun SY, Lee JJ, Lee SW, Han MC, Han CG. Strength monitoring of the wall concrete with insulation form and non-insulation form with wireless sensor network with equivalent age method. Proceeding of Korea Concrete Institute; 2018May 12-14; Kyungju (Korea). Seoul (Korea): Korea Concrete Institute; 2018. p. 659-60.
  7. Kim SM, Sin SJ, Seo HG, Kim J, Han MC, Han CG. Prediction of strength development of the wall concrete at jobsite applying wireless sensor network (CIMS) based on maturity. Proceeding of Architectural Institute of Korea; 2020 Mar 26-28; Seoul (Korea). Seoul (Korea): Architectural Institute of Korea; 2020. p. 397-8.
  8. Kim SM, Sin SJ, Hyun SY, Kyoung YH, Han MC, Han CG. Prediction of strength development of concrete at jobsite applying wireless sensor network (CIMS) based on maturity. Proceeding of Korea Concrete Institute; 2018 May 13-14; Seoul (Korea). Seoul (Korea): Korea Concrete Institute; 2020. p. 403-4.