凍結解凍環境下におけるナノTiO2-改造コンクリートの機械的特性
Chao Xu1, Lin Deng1,2, Dingtao Yang3
1School of Architecture and Civil Engineering, Huangshan University, 39 Xihai Road, Huangshan 245041, China.
Nanomaterials (Basel, Switzerland)
|August 27, 2025
まとめ
ナノTiO2改造コンクリート (NTC) は,通常のコンクリートと比較して,質量減少とよりよい強度保持で,凍結解凍抵抗性が向上しています. NTCは損傷を軽減しますが 骨折耐久性の利点は限られています
科学分野:
- 材料科学
- 土木工学
- ナノテクノロジー
背景:
- コンクリートの耐久性は インフラストラクチャの長寿に不可欠です
- 凍結解凍サイクルはコンクリート構造に重大な脅威をもたらし,劣化につながります.
- ナノ材料はコンクリートの性能を向上させる可能性を秘めています
研究 の 目的:
- 通常のコンクリートと比較して,ナノTiO2改変コンクリートの凍結解凍耐性を評価する.
- コンクリートの質量損失,超音波速度,圧縮強度,破裂強度に対する凍結解凍サイクルの影響を分析する.
- 粒子フローコード (PFC2D) シミュレーションを使用して実験結果を検証する.
主な方法:
- 繰り返された凍結解凍サイクルによる通常のおよびNTCの実験試験.
- 質量損失,超音波速度,圧縮強度,および断裂強さの測定
- 内部ダメージ分析のための二次元粒子フローコード (PFC2D) シミュレーション
主要な成果:
- NTCは,通常のコンクリートと比較して100回の凍結解凍サイクル後に,質量損失 (52.17%) が著しく減少し,超音速 (37.31%) が増加した.
- 圧縮強度の低下は,通常のコンクリート (24. 28 MPa減少) よりもNTC (13. 37 MPa減少) よりも軽かった.
- 両方の材料の断裂強度が大幅に低下し,NTCは通常のコンクリートの89.7%に対して80.9%の減少を示した.
結論:
- ナノ-TiO2の組み込みは,コンクリートの凍結解凍損傷に対する耐性を効果的に高め,特に圧縮強さを保ちます.
- NTCは全体的な分解を緩和しますが,重度の凍結解凍条件下での断裂耐久性を維持する能力については,さらなる調査が必要です.
- PFC2Dシミュレーションは実験結果を正確に反映し,コンクリートの凍結解凍分解をモデル化するための有用性を確認しました.
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