フライアッシュコンクリートの収縮と機械特性に対する温度制御添加物の影響:実験とモデリング
Yingda Zhang1, Haiyang Li1, Haojie Zhang1
1School of Architecture and Civil Engineering, Xihua University, Chengdu 610039, China.
Materials (Basel, Switzerland)
|August 28, 2025
まとめ
新しい温度制御添加物 (TCA) は,質量コンクリートの収縮と熱破裂を効果的に軽減します. 最適な0. 10%のTCA用量は,強度を大幅に改善し,より正確な収縮予測モデルにつながりました.
科学分野:
- 土木工学
- 材料科学
- 建設技術
背景:
- 大量のコンクリート構造は 早期の収縮や熱破裂に 直面しています
- 内部温度の上昇を制御することは 構造の健全性にとって極めて重要です
- 既存のモデルでは,改造コンクリート混合物の収縮を正確に予測することができません.
研究 の 目的:
- フライアッシュコンクリートの新型温度調節添加物 (TCA) の導入と評価
- TCAの収縮,熱特性,機械的安定性への影響を調査する.
- コンクリートにTCAを組み込むための改善された収縮予測モデルを開発する.
主な方法:
- 4つのフライアッシュコンクリート混合物の実験評価
- 縮小と温度上昇を測定するための制御された環境試験
- 実験結果を既存の収縮予測モデル (Eurocode 2, fib Model Code 2010, AS 3600, Bazant B4) と比較する.
- 改造された半経験的予測モデルの開発.
主要な成果:
- 最適のTCA用量は0. 10%で,縮小は27. 3%減少し,圧縮強度は12. 2%増加しました.
- 既存のモデルでは 294%まで 縮小が過大評価されています
- 提案された改変モデルは,0.08の変数係数で予測誤差を10%に引き下げました.
結論:
- 新型TCAは,質量コンクリートの早期収縮と熱的問題を軽減するのに有効です.
- コンクリートの収縮と水分輸送に対するTCA効果を正確に捉えるモデルを改造した.
- この研究は,TCAを使った高度なコンクリートシステムの設計に貴重な洞察を提供します.
関連する概念動画
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01:14Design Example: Managing Concrete Workability
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01:27Shrinkage in Concrete
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01:21Drying Shrinkage
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01:27Cold Weather Concreting
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