使用预应力近表面安装条的RC梁的剪切强化 降低施工失败风险的概率
Sabry Fayed1, Mohamed Ghalla1, Jong Wan Hu2,3
1Civil Engineering Department, Faculty of Engineering, Kafrelsheikh University, Kafr El-Sheikh 33516, Egypt.
Materials (Basel, Switzerland)
|December 17, 2024
概括
这项研究提高了钢筋混凝土 (RC) 梁的剪切能力,使用组合预应力和近表面安装 (NSM) 杆技术. 这些方法通过减轻故障风险,显著提高了结构安全性和建筑可持续性.
科学领域:
- 土木工程 土木工程是指土木工程.
- 结构工程 结构工程
- 材料科学 材料科学 材料科学
背景情况:
- 钢筋混凝土 (RC) 梁的剪切故障在建筑物中构成重大安全风险.
- 对于RC梁的现有增强方法在解决剪切关键故障方面存在局限性.
- 提高建筑物的安全性和可持续性需要有效的缓解RC光束故障的策略.
研究的目的:
- 调查结合预应力和近表面安装 (NSM) 杆技术的有效性,以加强切割关键的RC梁.
- 通过实验和数值分析强化RC梁的结构行为.
- 降低RC梁故障风险的概率,从而提高建筑物的安全性和可持续性.
主要方法:
- 十个RC梁被测试,其中九个使用各种技术加强:内部预应力 (IP),外部预应力NSM (PNSM) 和内部嵌入 (IE) 具有或没有预应力.
- 额外剪切强化比率 (μs) 在0.87%至1.60%之间.
- 结构性能是根据裂变负载,最终负载,负载偏移反应,最终偏移和刚度来评估的.
主要成果:
- PNSM棒 (μs = 1.45%) 增加了57.8%的剪切能力,而IP棒 (μs = 1.6%) 增加了70.4%的剪切能力.
- IE棒 (μs = 1.02%) 导致剪切能力增加了23.2%.
- 与外部预应力相比,内部预应力显示出更高的性能.
- 刚度增加了20%至84.4%,添加了内部预应力杆.
结论:
- 结合预应力和NSM杆技术是加强切割关键RC梁的有效方法.
- 预应力的位置显著影响剪切能力,内部预应力更有效.
- 提出了一种新的公式来计算各种方法加强的RC梁的剪切能力,有助于改进结构设计和安全.
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