高強度コンクリートの機械特性に対するスケール効果の研究
Marek Miazgowicz1, Lucyna Domagała2
1CUT Doctoral School, Faculty of Civil Engineering, Cracow University of Technology, 31-155 Kraków, Poland.
Materials (Basel, Switzerland)
|August 28, 2025
まとめ
試料の形状とサイズは,高強度コンクリートの性質に最小限の影響を及ぼします. コンクリートの内部構造と密度は,その弾性モジュールと圧縮強度に影響を与える主要な要因です.
科学分野:
- 材料科学
- 土木工学
- コンクリート技術
背景:
- 欧州標準 EN 12390-13は,コンクリートの試験のために様々な形状と大きさの試料を許可しています.
- 既存の規格では,試料の幾何学と弾性モジュールの関係に関する指針がない.
- 試料の寸法の変化は,測定されたコンクリートの機械的性質に影響を与える可能性があります.
研究 の 目的:
- 高強度のコンクリートの弾性および圧縮強度に対する試料の形状と大きさの影響を調査する.
- 試料の幾何学に基づいて測定された弾性モジュール (ダイナミックおよびセカン) と圧縮強さの違いを定量化します.
- コンクリートの機械的振る舞いに対する物質構造に対する試料の寸法の相対的な重要性を決定する.
主な方法:
- 64個の高強度コンクリート試料 (平均強度101.9MPa) の試験
- 大きさと細さの比率の異なる立方体と円筒形の標本を使用した.
- 異なる試料の幾何学を標準の円筒型試料 (150 × 300 mm) と比較した結果.
主要な成果:
- ダイナミック・モジュール・オブ・弾性 (Ed) の差は19%に達し,セカント・モジュール (Ec,s) の差は14%に達した.
- 試料のスケールと形状は,機械的性質に少ない影響を示した.
- コンクリートの内部構造と密度は,測定された性質に影響を与える主要な要因として特定されました.
結論:
- 高強度コンクリートの個々の構造と密度は,その弾性モジュールと圧縮強さの決定要因です.
- 試料の形状と大きさは,測定された機械的性質に比較的小さな影響を及ぼします.
- コンクリート試験における試料の幾何学の標準化は,材料特有の特性に基づいて再評価を必要とする場合があります.
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