コンクリートの耐久性について
Zhidong Zhang1, Ueli Angst1, Viacheslav Troian1,2
1Institute for Building Materials, ETH Zurich, Zurich, Switzerland.
Npj materials sustainability
|August 21, 2025
まとめ
炭酸化により,リサイクルされた粗材 (RA) のコンクリートの耐久性は,炭酸化でないRAと比較して13~55%向上します. リサイクルされたコンクリートの品質をさらに向上させるには,最適化された方法が必要です.
科学分野:
- 土木工学
- 材料科学
- 持続可能な建設
背景:
- リサイクルされた粗材 (RAs) はコンクリートでますます使用されています.
- RAsの炭素化は,その性質に影響を与える重要なプロセスです.
- RAコンクリートの耐久性に対する炭素化の影響を理解することは,持続可能な建設に不可欠です.
研究 の 目的:
- 炭酸リサイクル粗材 (cRAC) で作られたコンクリートの耐久性を評価する
- cRACの性能を天然積石と非炭化RAで作られたコンクリートと比較する.
- RAの品質を向上させるため,炭酸化プロセスを最適化するための方法を特定する.
主な方法:
- コンクリートの試料は炭酸RAを用いて作られました.
- cRACの耐久性指標を測定し,比較した.
- 炭酸RAの微細構造を分析した.
- 炭酸化プロセスの最適化戦略を調査した.
主要な成果:
- cRACの耐久性指標のほとんどは天然コンクリートの耐久性指標より低い.
- しかし,cRACの耐久性指標は,炭酸化でないRAを使用したコンクリートと比較して13~55%改善された.
- 炭化によりRAの密集した微細構造が形成され,コンクリートの性能が向上した.
結論:
- 炭化水素は,リサイクルされた粗石コンクリートの耐久性を大幅に高めます.
- 湿度管理とバイオマテリアルの使用を含む炭素化方法を最適化することで,RAの品質をさらに向上させることができます.
- cRACは従来のコンクリートに対する有望な持続可能な代替手段であり,さらなる性能向上の可能性があります.
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