一种混合有限离散元素方法,用于模拟在循环动态负载下含有单一边缘缺陷的沙泥石中裂变过程
Xiaolong Zhang1,2,3, Wenjie Xu4, Xiaoping Zhang5
1National Institute of Natural Hazards, Ministry of Emergency Management of China (NINH, MEMC), Beijing, 100085, China.
Scientific reports
|July 3, 2024
概括
本研究介绍了一种混合有限离散元素方法 (HFDEM),用于模拟动态负载下的岩石裂变. HFDEM准确地模拟了裂传播,并显示在高频循环负荷下岩石更强.
科学领域:
- 地质技术工程 地质技术工程
- 计算力学 计算力学 计算力学
- 岩石机械学 岩石机械学
背景情况:
- 岩石变形和破裂是复杂的过程,涉及裂的开始,传播和凝聚.
- 在循环动态负荷下模拟岩石从连续状态到不连续状态的过渡具有重大挑战.
研究的目的:
- 开发和验证混合有限离散元素方法 (HFDEM) 用于建模岩石裂传播和故障.
- 研究先前存在的缺陷倾斜和动态加载频率对岩石破裂机制的影响.
主要方法:
- 采用混合有限离散元素方法 (HFDEM),整合了依赖频率的凝聚性区域模型.
- 模拟是在准静态和循环动态负载条件下的标准沙泥石上进行的.
- HFDEM的结果与实验数据对机械性能和故障行为进行了验证.
主要成果:
- HFDEM成功捕获了裂相互作用机制,并准确地模拟了整体样本的故障.
- 岩石样本在动态负载下表现出明显更高的压力强度,相比于准静态负载.
- 压力强度随着更高的周期动态负载频率而增加,为故障机制提供了洞察力.
结论:
- HFDEM是一种可靠的工具,用于模拟动态负载下的岩石质量变形和故障.
- 动态加载频率显著影响岩石强度和故障模式.
- 这些发现为与地震负荷和岩石断裂分析相关的工程实践提供了宝贵的指导.
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