Journal of the Korean Recycled Construction Resources Institute (한국건설순환자원학회논문집)

Korean Recycled Construction Resources Institute (한국건설순환자원학회)
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Suggestion of a Evaluation Method for Variation of Concrete Workability According to Pumping Condition through Lab-Scale Test

펌핑 조건에 따른 콘크리트 작업성 변화 실내 평가 방법 제안

  • Lee, Jung-Soo (Hybrid Structural Testing Center, Myongji University) ;
  • Jang, Kyong-Pil (Department of Living and Built Environment Research, KICT) ;
  • Kwon, Seung-Hee (Department of Civil and Environmental Engineering, Myongji University)
  • 이정수 (명지대학교 하이브리드구조실험센터) ;
  • 장경필 (한국건설기술연구원 국민생활연구본부) ;
  • 권승희 (명지대학교 토목환경공학과)
  • Received : 2020.09.21
  • Accepted : 2020.10.30
  • Published : 2020.12.30
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Abstract

In this study, a new lab-scale test equipment was developed to evaluate the variation of concrete workability after pumping. The equipment was designed to simulate the pressure and shearing applied to concrete during actual pumping. In order to examine the feasibility of evaluating variation of concrete workability through lab-scale test equipment, real-scale pumping tests and lab-scale tests were performed together. The design strength of concrete used in the both tests was 24, 35, and 60MPa, and the length of pipe used in pumping tests was 130, 304, and 518m. The lab-scale tests were performed in consideration of actual pumping conditions(pressure, shearing, and pumping duration time). The workability(slump or slum flow) of concrete was measured before test, after the pumping test, and after lab-scale test. In all tests, workability of all concrete mixtures decreased. In addition, the results of both tests were measured greatly similarly.

이 연구에서는 펌핑 후 콘크리트의 작업성 변화를 실내에서 평가하기 위한 새로운 실험 장비를 개발하였다. 이 장비는 실제 펌핑 중 콘크리트가 받는 압력과 전단을 모사할 수 있도록 설계되었다. 실내 실험 장비를 사용한 펌핑 후 콘크리트 작업성 변화 평가 가능성을 검토하기 위하여 실규모 펌핑 실험과 실내 모사 실험을 동시에 수행하였다. 실규모 펌핑 실험에 사용한 콘크리트의 설계기준압축강도는 24, 35, 60MPa이며, 배관의 길이는 130, 304, 518m이다. 펌핑 실험과 동일한 콘크리트를 사용하여 실제 펌핑 조건(압력, 전단, 펌핑 시간)을 고려한 실내 모사 실험을 수행하였다. 실험 전, 실규모 펌핑 실험 후, 실내 모사 실험 후 콘크리트의 작업성(슬럼프 또는 슬럼프 플로)을 측정하였다. 실규모 펌핑 실험과 실내 실험 모두 콘크리트의 작업성이 감소하였으며, 두 실험의 결과가 매우 유사하게 측정되었다.

Keywords

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