鉄筋コンクリートビームの屈曲性能 鉄筋コンクリートビームの屈曲性能 鉄筋コンクリートビームの屈曲性能
Naila Hisbani1, Muhammad Alamgeer Shams1, Mohammad Ajmal Stanikzai2
1Civil Engineering Department, University of Technology Petronas, Ipoh, Malaysia.
Scientific reports
|August 26, 2025
まとめ
石膏鉄筋コンクリート (RC) のビームは,石膏でないビームと比較して耐火性が向上しています. この研究では 石膏は 構造性能と 火災の発生後の残留モメント能力を 大きく向上させることが示され 建物の安全性にとって 極めて重要です
科学分野:
- 土木工学
- 材料科学
- 構造工学
背景:
- 鉄筋コンクリート (RC) 構造物の火災分析は,極端な条件下での構造的整合性を評価するために不可欠です.
- 制御不能な火災は,建物やインフラに重大なリスクをもたらし,安全性と信頼性を損なう可能性があります.
研究 の 目的:
- 火に晒されたRCビームの構造性能と残留モメント能力を評価する.
- RCビームの耐火性を比較するには,異なる強化構成と石膏処理が必要です.
主な方法:
- 強化が異なるRCビーム (下部に2または3バー,上部に2バー) を試験した.
- ビームは,シミュレートされた火の条件 (ピーク800°C) に0時間,3時間,6時間さらされた.
- 火災後の構造性能を評価するために残留モメント容量を測定しました.
主要な成果:
- RCビームのモメント容量が20~36%減少し,強化によって変化した.
- 石膏状のビームは,優れた構造性能を示し,石膏状のビームと比較して高い残留モメント能力を保持しました.
- 火災による劣化に対する保護層としての石膏の有効性は明らかでした.
結論:
- 石膏は重要な保護層として機能し,RCビームの耐火性と火災後の構造性能を大幅に高めます.
- 火災による劣化を軽減し,RC構造物の全体的な安全性を改善するために,石膏コーティングを組み込むことは不可欠です.
- RCビームの設計上の考慮事項には,長期にわたる構造的整合性を確保するために,石膏のような耐火対策が含まれます.
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