ハイブリッド鉄筋コンクリートビームの耐用性および柔らかさ,部分的に工学セメント複合材料 (ECC) で構成される
Ahmed A Radwan1, Ahmed Ghallab2, Ahmed M Farghal Maree2
1Department of Structural Engineering, Ain Shams University, Cairo, Egypt. ahmed.alaa@eng.asu.edu.eg.
Scientific reports
|August 21, 2025
まとめ
この研究では,ガラス繊維強化ポリマー (GFRP) またはハイブリッド鋼-GFRPバーとエンジニアリングセメント複合材料 (ECC) で強化されたコンクリートビームを調査しました. 結果は,ECCがビームの性能を向上させ,U形の構成が柔らかさを向上させることを示しています.
科学分野:
- 土木工学
- 材料科学
- 構造工学
背景:
- コンクリートビームの鋼鉄強化の腐食は,特に厳しい環境で重要な問題です.
- ガラス繊維強化ポリマー (GFRP) 棒は,鋼の耐腐蝕代替品を提供します.
- エンジニアリングセメント複合材料 (ECC) とハイブリッド強化 (鋼-GFRP) はコンクリートのビームの強さと使用能力を高めることができます.
研究 の 目的:
- GFRPバーのみを使用するコンクリートビームの傾斜と柔らかさを調査するか,部分的にエンジニアリングされたセメント複合材料 (ECC) を使用したハイブリッド鋼-GFRPバーを使用する.
- ビームの振る舞いに対するECC構成 (厚さやU形) の影響を評価する.
- これらの複合ビームの傾斜予測方程式の精度を評価する.
主な方法:
- GFRPまたはハイブリッド強化の制御ビームと部分ECCビームを6つ組み立てました.
- 試料は,裂け目パターン,モメント・ストレンス,モメント・カーブチャーの関係を分析するために,四点曲折試験を受けた.
- ACI 318-19,CSA S806-12およびACI 440.1R-15からの偏差方程式は,実験データに対して評価された.
主要な成果:
- 張力ゾーンの厚いECC層は,亀裂の分布,硬さ,エネルギー吸収を変化させました.
- U型ECCの構成は,一般的に柔らかさ指数を増加させた.
- 波紋表面の施工技術は,インターフェースの切断移転を改善し,結合障害を防止しました.
- ACI 318-19とCSA S806-12の傾斜方程式は実験結果と良好な相関関係があり,ACI 440.1R-15は不一致を示した.
結論:
- GFRPまたはハイブリッド補強とECCの部分的な使用は,コンクリートのビームの腐食問題を軽減するための実行可能な解決策を提供します.
- ECCの構成はビームの性能に大きく影響し,U形のデザインは柔らかさを高める.
- ハイブリッドビームのインターフェイス結合を改善する特殊な施工技術があります.
- 既存の歪み予測コードは,ECC鉄筋コンクリートビームの正確な評価のために精細化する必要があります.
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