建立和工程应用粘弹性-塑料构成定律,用于在交叠岩层中的爬行模型
Taotao Hu1, Shaojun He2, Zhibin Kang3
1School of Highway, Chang'an University, Xi'an, 710064, China. tthu@chd.edu.cn.
Scientific reports
|November 24, 2023
概括
这项研究引入了一个新的七元素粘弹性-塑料模型来分析道爬行行为在交叠的岩石群体. 该模型在ABAQUS中实现,揭示了岩石倾斜如何影响道变形和表面沉积.
科学领域:
- 地质技术工程 地质技术工程
- 岩石力学 岩石力学 岩石力学
- 计算力学 计算力学 计算力学
背景情况:
- 在交叠的岩石群体中挖掘道,由于时间依赖的变形 (爬行) 带来了挑战.
- 了解爬行行为对于确保道的稳定性和安全性至关重要.
研究的目的:
- 开发和验证一种新的粘弹性塑料七元模型,用于分析道爬行.
- 研究不同岩石倾斜角度对道变形和表面沉积的影响.
主要方法:
- 开发一个具有应力值的七元素粘弹性-塑料模型.
- 在三维应力状态下导出爬行方程.
- 在ABAQUS软件中实现一个用户定义的材料 (UMAT) 子程序.
- 使用rheological测试结果进行验证.
- 与不同岩石倾斜度 (α) 相交的岩石道的数值模拟.
主要成果:
- UMAT子程序有效地模拟了爬行行为,经过rheological测试验证.
- 岩石的斜率显著影响水平移位,表面沉降和道段的收.
- 水平面位移是不对称的,在0°,45°和90°的倾斜处是相当的.
- 表面沉降呈现出非单调的趋势,最高点在0°,最低点在45°.
- 道截面的收变化;门顶部/底部的收下降,而门腰部/肩部的收显示出基于倾斜的相反趋势.
结论:
- 拟议的七元模型和UMAT子程序为分析道爬行在交叠岩层中提供了可靠的工具.
- 岩石倾斜是影响道稳定性和变形特征的关键因素.
- 这些发现为在复杂的地质条件下设计和建造道提供了宝贵的见解.
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