unstable roof meaning in English
脆性顶板
Examples
- Research and application of working face unstable roof treatment technique
采煤工作面不稳定顶板治理技术的研究与应用 - Practices on bolt , mesh , anchor and beam support in coal drift under unstable roof condition of cataclastic rock mass
不稳定顶板煤巷锚网索梁支护实践