セメントの水和反応・組織形成モデルを用いたコンクリート部材中の水分拡散および熱伝導シミュレーション

• 杉山 央

  宇都宮大学地域デザイン科学部

書誌事項

タイトル別名

• SIMULATION OF WATER DIFFUSION AND HEAT CONDUCTION IN CONCRETE MEMBER USING MATHEMATICAL MODEL FOR CEMENT HYDRATION AND MICROSTRUCTURE FORMATION

抄録

Water content and temperature of concrete have an influence on various properties of concrete. For example, water content and temperature of concrete in the hardening process have an influence on the strength development. The change of water content after the hardening participates in the durability of concrete. Furthermore, water content and temperature are different by the position in the concrete when it is scaled the full-size concrete member. Therefore, the prediction of water content and temperature in the concrete member is important. In this study, water content and temperature in the concrete member were numerically predicted using the mathematical model for cement hydration and microstructure formation. The mathematical model for cement hydration and microstructure formation has been proposed in the previous study. The model dealt with the diffusion of water into cement particles and the diffusion of cement components out of cement particles. The model made it possible to express not only the progress of cement hydration but the progress of formation of the hydrated cement microstructure. The simulation model for water diffusion in full-size concrete member was proposed. This model made it possible to express the water consumption by cement hydration, water diffusion in concrete member, and water evaporation from the surface of concrete after removing forms. Water content at each position in concrete member could be calculated by the model. The simulation model for heat conduction during heat generation caused by cement hydration was proposed in the previous study. The previous model was improved in this study, by introducing the effect of radiation heat and evaporation heat of water on the surface of concrete. Temperature at each position in concrete member could be calculated by the improved model. Furthermore, the heat conduction model was connected with the water diffusion model. The predicted water contents were compared with the measured water contents of wall and column specimens. As a result, it was confirmed that the predicted water contents agreed with the measured water contents. In the N28.3 and N48.4 concrete column specimens, the water content after removing forms was the smallest on the corner of the column and largest at the center. The difference in the water content of the center and corner was especially noticeable in the N48.4 concrete. In the N48.4 concrete wall specimen, the water content after removing forms is nearly constant at 100 mm or deeper from the surface. This suggests that at deeper than 100 mm from the surface, the water content is not affected by water dissipation to the outside of concrete but mainly by the cement hydration in the concrete interior. The predicted concrete temperatures were compared with the measured concrete temperatures of column specimens. As a result, it was confirmed that the predicted temperatures agreed with the measured temperatures. Especially, the tendency that the drop in temperature caused by water evaporation from the surface of concrete after removing forms could be predicted accurately.

収録刊行物

• 日本建築学会構造系論文集

  日本建築学会構造系論文集 86 (784), 848-859, 2021-06-30

  日本建築学会

キーワード

• コンクリート部材
• 含水率
• 温度上昇
• セメント水和反応
• 脱型
• 予測モデル

詳細情報

• CRID: 1390288535620908416
• NII論文ID: 130008058802
• NII書誌ID: AN10438559
• DOI: 10.3130/aijs.86.848
• ISSN: 18818153
• ISSN: 13404202
• Web Site: https://www.jstage.jst.go.jp/article/aijs/86/784/86_848/_pdf
• 本文言語コード: ja
• データソース種別:
  • JaLC
  • Crossref
  • CiNii Articles
  • KAKEN
• 抄録ライセンスフラグ: 使用不可