一个数值研究的动态裂纹行为易碎的材料诱导的冲击波
Haijun Yu1,2,3,4, Ming Zou3, Jinshan Sun1,2
1State Key Laboratory of Precision Blasting, Jianghan University, Wuhan 430056, China.
Materials (Basel, Switzerland)
|November 25, 2023
概括
裂的长度显著影响了爆炸应力波如何启动和传播沙石等脆性材料的裂. 较短的裂产生P波和S波,而较长的裂则利用雷利波进行传播.
科学领域:
- 工程机械 工程机械 工程机械
- 材料科学 材料科学 材料科学
- 计算机建模 计算建模
背景情况:
- 爆炸应力波对工程结构构成重大风险.
- 易碎的建筑材料在动态负荷下容易破裂.
- 了解压力负荷下的裂行为对于结构完整性至关重要.
研究的目的:
- 为了研究爆炸应力波下的裂启动和传播.
- 分析裂前长度对裂动态的影响.
- 开发一种新的数值模型来模拟爆炸引起的骨折.
主要方法:
- 为钻井孔裂配置开发了一种新的数值模型.
- 创建了12个模拟不同裂长度的砂岩样本的模型.
- 使用了状态的线性方程和主要的主要应力失效标准.
- 一个三角形的压力曲线模拟了爆炸应力波.
主要成果:
- 裂前的长度对裂启动和传播机制产生了关键的影响.
- 分析了裂纹尖端的压力历史,传播速度和距离.
- 在短预裂模型中,P波和S波诱导至关重要.
- 雷利波对长度裂前模型中的裂传播有显著的贡献.
结论:
- 裂纹长度是爆炸引起的裂纹动态的一个关键参数.
- 波传播机制 (P,S和雷利波) 取决于裂前的长度.
- 数值模型提供了关于在高压下断裂行为的见解.
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