3D DEM 分析颗粒破裂效应在粗沙直接剪切试验中的3D DEM 分析
Mohamed Amine Benmebarek1, Majid Movahedi Rad1, Sadok Benmebarek2
1Department of Structural and Geotechnical Engineering, Faculty of Architecture, Civil Engineering and Transport Sciences, Széchenyi István University, Egyetem tér 1, 9026 Győr, Hungary.
Materials (Basel, Switzerland)
|July 29, 2023
概括
在粗沙中的颗粒破裂显著改变了机械行为. 模拟显示压碎降低了剪切应力,增加了体积应力,在直接剪切试验中导致收缩而不是扩张.
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
- 材料科学 材料科学 材料科学
背景情况:
- 颗粒破裂是影响颗粒材料机械反应的关键因素.
- 了解谷物粉碎对于准确建模压力下的土壤行为至关重要.
研究的目的:
- 为了研究颗粒破裂对粗沙机械行为的影响.
- 分析宏观和微观机械反应,包括应力-应变,体积变形和谷物粉碎演变.
- 为了比较可粉碎和不可粉碎的沙粒的行为.
主要方法:
- 采用了三维离散元件方法 (DEM) 模拟.
- 直接切割试验 (DST) 用非可粉碎和可粉碎粒子模型进行模拟.
- 在剪切区域的各种高正常应力下进行了模拟.
主要成果:
- 可粉碎颗粒在峰值剪切应力时显示部分粉碎,并在临界状态时产生显著的罚款.
- 微粒因压力和重力而迁移并积聚在较低的模拟盒中.
- 颗粒粉碎导致剪切应力降低和体积应力增加,导致收缩行为.
结论:
- 颗粒破裂从根本上改变了粗沙的应力-应变和体积反应.
- 粉碎的现象促进了收缩行为,与通常在非可粉碎材料中观察到的膨胀形成鲜明对比.
- DEM模拟为控制可粉碎颗粒土壤行为的复杂微机械过程提供了宝贵的见解.
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