摘要
针对深部地下工程底板冲击失稳的相关特点,提出了采用四体构件模拟煤岩体结构,运用FLAC3D数值软件模拟试件真三轴压缩过程,通过不同中间主应力系数和卸载路径模拟深部开采环境,从构造应力和能量角度出发,分析了深部开采底板冲击相关特点。结果表明:当从最小主应力方向卸载时,卸载后到底板冲击发生所经历的时间较卸载中间主应力时长;不同的卸载方向导致底板冲击所经历的时间步与中间主应力系数呈指数关系,当卸载最小主应力时,煤层开采到发生冲击所经历的时间步与中间主应力系数成指数关系上升,而卸载中间主应力时反之;发生冲击的岩体经历了脆—延—脆—塑的转化过程。
According to the related features of the floor rock burst and stability lost occurred in the deep underground project, a simulated coal and rock mass structure with four - pieces Component was applied and the FLAC3D numerical software was applied to simulate the real triaxial compression process of the specimen. With a different intermediate principal stress coefficient and an unloading path applied to simulate a deep mining environment, from a view of the structural stress and energy, the paper analyzed the related features of the floor rock burst occurred in the deep mining. The results showed that when a unloading was in a direction of the rain principal stress, the time when the floor rock burst occurred after the unloading completed was longer than the time of the intermediate stress unloaded. Different unloading direction would cause the occurred time step of the floor rock burst and the intermediate principal stress coefficient being an index relationship. When a min principal stress unloaded, the occurred time step from the seam mining to the rock burst occurred and the intermediate principal stress coefficient would be increased in an index relationship and when the intermediate principal stress unloaded, the index relationship would be reversed. The rock mass after rock burst occurred would have a fragile - extension - fragile - plastic conversion process.
出处
《煤炭工程》
北大核心
2014年第1期98-101,共4页
Coal Engineering
基金
国家自然科学基金项目(51204102)
国家重点基础研究发展计划(973)子课题(2010CB226805-02)
山东科技大学研究生科技创新基金(YC130304)
关键词
底板冲击
真三轴压缩
四体构件
FLAC3D数值试验
中间主应力系数
floor rock burst
real triaxial compression
four- piece component
FLAC3D Numerical test
intermediate principal stress coefficient
