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基于圆形空洞切割模式的损害预测和改进方法
Huifeng Qin1, Yan Zhao2,3,4,5, Hailong Wang1,6,7
1Hebei University of Architecture, Hebei, 075000, China.
Scientific reports
|May 17, 2024
概括
这项研究调查了切割喷射中的岩石质量失败,这项研究揭示了正方形的空洞,与圆形的不同,诱导了显著的拉伸和剪切失败,导致内部崩和更高的空间利用率. 圆形孔表现出周期性应力演变与抑制反射波.
科学领域:
- 岩石机械 岩石机械 岩石机械
- 爆破工程工程 爆破工程
- 地质技术工程地质技术工程
背景情况:
- 空洞效应在切割喷射中至关重要.
- 了解岩石质量中的动态应力演变和断裂机制对于优化爆破操作至关重要.
研究的目的:
- 建立一个2D计算模型,用于洞壁中的动态应力演变.
- 预测在纵向波动下岩石质量中的动态断裂机制和损伤分布.
- 为了比较圆形与方形空洞的故障机制和空间利用.
主要方法:
- 整合霍普金森效应和圣维南特原理来建模动态应力.
- 开发一个二维计算模型用于孔壁应力.
- 计算和数值模拟结果的实验验证.
- 圆形和方形空洞模型的比较分析.
主要成果:
- 理论计算与模拟结果一致,显示了圆形腔中的周期性动态应力演变.
- 洞形状显著影响岩石质量失效:圆形洞经历"间隔环"破坏,而方形洞表现出广泛的拉力和剪切失效.
- 方形空洞的空间利用率是圆形洞的8.5倍.
- 圆形的空洞产生更大的振动效应,岩石破裂能量比例较低.
结论:
- 空洞的形状严重影响岩石质量故障模式和切割喷射中的空间利用.
- 与圆形洞相比,正方形空洞在促进岩石质量破裂和空间利用方面更有效.
- 进一步研究优化空洞几何形状,以适用于特定的喷射应用是有必要的.
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