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A Proposal for Improving the Measurement and Management of Unit Water Content in In-Situ Concrete

현장 타설 콘크리트의 단위수량 측정 및 관리 개선 방안 제시

  • Yun, Ja-yeon (School of Architectural, Civil, Environmental, and Energy Engineering, Kyungpook National University) ;
  • Jang, Hyo-Jun (KCC construction) ;
  • Lee, Taegyu (Department of Fire and Disaster Prevention, Semyung University) ;
  • Choi, Hyeonggil (School of Architecture, Kyungpook National University)
  • Received : 2024.03.05
  • Accepted : 2024.04.11
  • Published : 2024.06.20

Abstract

This study examined domestic and international regulations concerning concrete unit weight, along with an evaluation of unit weight in concrete poured on construction sites. Fluctuations in unit weight were observed to correlate with concrete quality issues such as material separation, bleeding, and latency. A word cloud analysis, centered on the concept of concrete quality, further highlighted the significant influence of unit weight. Comparative analysis between Korea and Japan revealed few substantial differences in unit weight management and measurement techniques. However, calculation of concrete unit weight at delivery, using the unit volume mass method, indicated considerable variability among random on-site samples. Notably, the unit weight often exceeded the recommended standard. These findings emphasize the necessity for strict adherence to unit weight standards by all stakeholders involved in concrete production and construction, including ready-mix concrete (REMICON) producers, construction firms, and inspectors. To ensure consistent quality of cast concrete on-site, the establishment of a more comprehensive and practical system is recommended, incorporating measures such as on-site inspections.

본 연구에서는 국내외 단위수량 규정을 조사하고 현장 타설 콘크리트의 단위수량을 평가하였다. 콘크리트 품질을 타이틀로 하여 핵심 단어 시각화했을 때 단위수량이 높은 중요도를 가짐을 확인할 수 있었다. 또한 단위수량 관리 및 단위수량 측정 방법에서 한국과 일본 간 상대적으로 큰 차이가 나타나지 않음을 알 수 있었다. 현장에 반입된 콘크리트의 단위수량을 단위용적질량법을 이용하여 계산한 결과, 현장에서 임의로 채취한 샘플에서 단위수량이 불균일하고 가변적이며, 단위수량이 적정 단위수량 기준을 초과하는 결과를 확인할 수 있었다. 현장 타설 콘크리트의 품질관리를 위해서는 레미콘 업체, 건설업체, 검사관이 단위수량에 대한 엄격한 기준을 준수하는 것이 중요하며, 명확한 단위수량 측정 매뉴얼 제공과 철저한 교육, 주기적인 현장 점검 등 보다 체계적이고 실용적인 시스템 구축이 필요하다고 판단된다.

Keywords

Acknowledgement

This research was funded by the Korea Agency for Infrastructure Technology Advencement(KAIA) grant funded by the Korean government(MOLIT)(grant number RS-KA162704) and the National Research Foundation of Korea(NRF) grant funded by the Korea government(MSIT)(NRF-2021R1C1C1011347).

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