研究动态损伤特征和数值模拟的低温冰扩展岩石在冲击负荷下的研究
Caixian Chen1,2, Shuai Cao3
1Tibet Julong Copper Co, Lhasa, 850000, China.
概括
这项研究检查了结,膨胀和冲击下的岩石特性,优化了高海拔采矿的爆破参数. 岩石强度因温度而异, -20°C产生了最高的动力强度.
科学领域:
- 地质技术工程 地质技术工程
- 岩石机械 岩石机械
- 爆炸物工程 爆炸物工程
背景情况:
- 低温冷膨胀周期显著改变了岩石的特性,影响了机械行为.
- 由于环境条件和岩石质量特征,高海拔开放露台的爆炸带来了独特的挑战.
- 了解合效应下的动态岩石特性对于安全高效的采矿操作至关重要.
研究的目的:
- 为了研究岩石在低温冷膨胀和冲击的联合作用下的动态性质.
- 为了优化高海拔开放露台喷气作业的喷气参数.
- 分析岩石在不同深度和低温下的动态强度特征.
主要方法:
- 利用霍普金森压缩棒模拟实验和波速测试来研究内部裂的发展和动态特性.
- 在霍普金森测试中使用LS-DYNA数值模拟软件,分析裂膨胀和应力波传播.
- 在LS-DYNA中开发了2D和3D喷气模型,以优化高空和阶段喷气场景的参数.
主要成果:
- 动态岩石强度在-20°C环境中最高,在-10°C环境中最低.
- 数字模拟结果与室内测试结果密切匹配,验证了模拟在预测动态损坏方面的准确性.
- 为特定的高海拔采矿应用确定了优化的爆破参数,包括朱龙铜业.
结论:
- 这项研究为结合低温和冲击条件下的岩石行为提供了基本的理解.
- LS-DYNA模拟有效地复制了动态岩石损伤的室内实验结果.
- 这些发现为改善在高海拔环境中具有挑战性的爆炸和采矿策略提供了宝贵的见解.
相关概念视频
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