肋骨增强条的残余应力 肋骨增强条的残余应力
Tobias Robl1, Patrick Hegele1, Christian Krempaszky1
1Institute of Materials Science, Department of Materials Engineering, TUM School of Engineering and Design, Technical University of Munich, 85748 Garching, Germany.
Materials (Basel, Switzerland)
|January 11, 2024
概括
这项研究调查了用于混凝土结构的肋骨钢筋条 (钢筋条) 的残余应力. 实验和数值方法揭示了核心的拉力应力和肋骨的压力,在关键的肋脚区域有拉力应力.
科学领域:
- 材料科学 材料科学 材料科学
- 结构工程 结构工程
- 机械工程 机械工程
背景情况:
- 条纹钢筋 (钢筋) 对于混凝土结构至关重要,在使用过程中会受到循环负荷.
- 铁杆的疲劳性能可能会受到制造过程中的残余应力的影响.
- 目前对铁杆残余应力的知识有限,特别是在关键疲劳裂开始地点.
研究的目的:
- 实验测量和数值模拟带钢筋中的残余应力.
- 为了研究横横肋骨的足半径区域的残余应力状态,通常是疲劳裂开始的地方.
- 提高对残余应力来源及其在钢筋中的分布的理解.
主要方法:
- 在28毫米直径的B500B钢筋样本上进行了实验残余应力测量.
- 进行了TempCoreTM制造过程的数值模拟.
- 实验和数值结果的比较,以验证模型和发现.
主要成果:
- 在钢筋的核心和过渡区域观察到拉伸余应力.
- 在非肋骨表面测量了低压力余应力,在肋骨尖处测量了高压力.
- 数字模拟在质量上重现了表面下的高应力梯度,并在肋脚半径区域显示了中等的拉力应力.
结论:
- 该研究提供了关于关键杆位置的残余应力的新型实验数据.
- 数字模型有效地模拟了剩余应力分布,包括复杂的表面层效应.
- 这些发现有助于更好地了解钢筋疲劳行为和结构完整性.
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