• Title/Summary/Keyword: high and ultra-high strength concrete

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Microstructure and Properties of Mortar Containing Synthetic Resin using Image Analysis (이미지 분석을 활용한 합성수지 혼입 모르타르의 특성 및 미세구조 분석)

  • Lee, Binna;Min, Jiyoung;Lee, Jong-Suk;Lee, Jang-Hwa
    • Journal of the Korea Concrete Institute
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    • v.28 no.1
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    • pp.59-65
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    • 2016
  • Commercial synthetic resins with great amount of hydrogen atoms were investigated for neutron shielding aggregates. Total three types of resins were considered in this study: high density polyethylene (HDPE), polypropylene (PP), and ultra molecular weight polyethylene (UPE). When these resins replaced 20, 40, 60 vol% of fine aggregates, mechanical properties were first evaluated including compressive and tensile strengths, and then image/microstructure analyses such as cross-section analysis, SEM, and X-ray CT were performed. The results showed that the compressive and tensile strengths decreased with the increase of replacement ratio of HDPE and PP, which was found through image analysis that it was closely related to the distribution of resins at the failure surface of test specimens. The strength reduction of UPE was quite small compared to HDPE and PP but it abruptly increased when the replacement level exceeded 60 vol%. The results of microstructure analyses indicated that the replacement level significantly affected the amount of air void so that it is critical to determine the reasonable amount of UPE to make cementitous materials for neutron shielding.