摘要
采用理论分析、数值模拟与现场试验相结合的方法,对忻州窑煤矿5931巷道卸压槽防冲效果进行研究。数学推导了巷道底板岩层轴向力,分析了巷道底鼓原因。根据煤岩体静载破坏理论,确定了巷道卸压槽防冲技术方案。并运用FLAC3D数值软件模拟布置卸压槽巷道围岩应力、变形状态,从模拟结果可以看出,卸压槽具有很好的防冲作用。最后,选取部分5931巷道开展卸压槽防冲试验,布槽巷道围岩变形量明显减小,与模拟结果较为一致,同时,声发射现象显著减弱,证实卸压槽有好的防冲效果。
This paper attempts to make a simulated testing exploration of the rock-burst preventive measures in the pressure-relief slots in No. 5931 Roadway of Xinzhou-pit coal mine. We have finished our numerical simulation and field tests through the theoretical analysis and mathematic deduction. According to the theory of coal or rock formation and evolutionary theory under the static loads,we have chosen the pressure-relief slot in No. 8931 roadway as the technical approach to the rockburst prevention in No. 5931 roadway and started our simulated research by using the FLAC3 Dsoftware for the response of the surrounding rocks to the excavating pressure-relief slot in the aforementioned roadway.When the simulation is done in the contrast group with no pressure-relief slot on the roadway floor,the maximum convergence of the both sides is 12. 2 mm whereas the maximum shear stress and principal stress are 12. 7 MPa and- 43 MPa,respectively,with the local shear failure coming up in the nearby roadway rocks. In contrast,when the pressure-relief slot is arranged in the roadway floor,the corresponding data are equal to 6. 4 mm,12 MPa and- 40 MPa under the simulated situation with the stress distribution of the surrounding rock having been changed. At the same time,the floor plastic zone has been extended to the bottom of the pressure-relief slot with a large amount of elastic energy released.Thus,the simulation results indicate that the rockburst prevention role of pressure-relief slot should be regarded as being positive and in turn confirmed by the related results. In the field tests of excavating pressure-relief slot of No. 8931 roadway,the deformation of the surrounding rock under observation is also basically consistent with the simulation results,which took place in the area where there is no pressure-relief slot even twice as much as that where the pressure-relief slot is provided with. However,the maximal acoustic emission rate of No. 2 monitoring point under test by the acoustic emission sensors accounts for 2 733 × 1
出处
《安全与环境学报》
CAS
CSCD
北大核心
2015年第5期48-53,共6页
Journal of Safety and Environment
基金
国家自然科学基金项目(51374124)
关键词
安全工程
冲击地压
卸压槽
FLAC3D
声发射
safety engineering
rockburst
pressure-relief slot
FLAC3D
acoustic emission
