超厚煤层道路的故障特性及其控制技术
Yiming Zhao1, Nong Zhang1, Jian Wang2
1School of Mines, China University of Mining and Technology, Xuzhou, China.
Heliyon
|January 25, 2024
概括
传统的支与道路屋顶沉入超厚的煤层作斗争. 一种新的增强支技术有效控制了顶部煤炭断裂,并将周围岩石变形减少50%,挖掘速度增加33%.
科学领域:
- 采矿工程 采矿工程 采矿工程
- 地质技术工程 地质技术工程
- 岩石机械学 岩石机械学
背景情况:
- 传统的支对于控制道路屋顶沉入超厚煤层的情况是不够的.
- 这种限制会对挖掘效率产生负面影响,并导致采矿比例失衡.
- 现有的方法无法解决这些环境中顶层煤的复杂变形和故障机制.
研究的目的:
- 为了研究屋顶应力分布和变形特征在超厚的煤层采矿过程中.
- 揭示不同条件下的顶层煤的故障机制.
- 开发和验证一种新的增强支技术,以提高道路稳定性和挖掘效率.
主要方法:
- 模拟的屋顶应力分布在一个典型的采矿道路与超厚的煤层.
- 分析了分层屋顶层和顶层煤的变形和故障特征.
- 开发并应用了一种强化支技术,涉及厚厚的 anchorage 和高预负载.
主要成果:
- 揭示了顶层煤的逐渐碎片化和不连续的变形/故障机制.
- 强化支技术有效控制了顶层煤的断裂损伤.
- 周围岩石变形减少了40%-50%,挖掘速度增加了33%.
结论:
- 拟议的增强支技术,利用厚和高预负载,对于超厚的煤层采矿非常有效.
- 与传统支相比,这种方法显著提高了道路稳定性和挖掘效率.
- 这些发现为挖掘超厚煤层所带来的技术挑战提供了可行的解决方案.
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