负载率和弧边界对动态负载下的脆性材料的动态裂纹阻断行为的影响
Lin Lang1,2, Shuang Tian3, Quan Yuan3,4
1School of Architecture and Civil Engineering, Xihua University, Chengdu, 610039, China. langlinwww@xhu.edu.cn.
Scientific reports
|April 17, 2025
概括
弧边界在动态负载下有效地阻止PMMA标本中的微裂. 较高的加载率增加了裂纹速度,减少了启动时间,阻断性超过了传播性.
科学领域:
- 材料科学 材料科学 材料科学
- 岩石机械 岩石机械
- 断裂力学 断裂力学 断裂力学
背景情况:
- 岩石中的微裂纹传播对于岩石质量结构的稳定性至关重要.
- 动态加载率显著影响岩石断裂特征.
研究的目的:
- 在动态冲击下的聚甲基甲酸盐 (PMMA) 样本中研究弧边界设计的裂纹阻断能力.
- 分析不同加载速率对裂启动,传播和停止行为的影响.
- 为了确定沿裂纹轨迹的动态断裂性和应力分布.
主要方法:
- 落撞击测试和裂生长仪测量以捕捉裂的开始和扩散.
- 扫描电子显微镜 (SEM) 用于分析微观断裂表面特征.
- 有限元法 (FEM) 用于计算裂纹尖端的动态断裂性.
主要成果:
- 弧边界设计在阻止裂传播方面被证明是有效的.
- 增加的加载率导致了更高的裂速度和更短的裂启动时间.
- 沿裂纹路径的峰值压力应力随着负载率的增加而增加,样本角度影响应力分布.
- 动态停止性被发现大于动态启动和传播性.
结论:
- 弧边界在动态加载场景中提供了一个可行的策略来阻止裂.
- 负载率是影响动态断裂行为和性的关键参数.
- 了解动态断裂力学对于设计稳定的岩石质量结构至关重要.
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