摘要
通过对大倾角煤层软岩回采巷道失稳特征的理论分析,建立了大倾角煤层软岩回采巷道围岩失稳状态方程,结合耦合支护思路分析,提出了大倾角煤层软岩回采巷道耦合支护方案,并运用数值计算、相似模拟实验及现场支护试验监测对回采巷道耦合支护方案进行综合分析。结果表明:回采巷道顶板失稳呈弧形非对称破断,两帮失稳主要表现为三角形破断体剪切滑移,破坏严重处位于帮角上部,顶板偏中上部破断是围岩失稳诱发点,围岩稳定性与煤层倾角、剪切面长度及煤岩体物理力学参数有关。巷道支护后,沿煤层倾向围岩塑性破坏区较小,顶板离层量保持在合理范围内,提高两帮支护强度利于巷道围岩稳定。
In this paper, through the theoretical analysis of instability characteristics of soft rock gate- way in high pitched seam, the structured instability equation of the gateway is established, and the cou- pling support scheme is proposed according to the coupling support idea. Additionally, the comprehen- sive analysis of the coupling support scheme is further carried out by numerical calculation, similar simulation experiment and practical supporting test. The results show that the instability of gateway roof has an arc asymmetry breaking, while the instability of two sides mainly shows shear slip of the triangle breaking bodies. The serious breaking lies in the upper of side angle, and the breaking in the mid- dle-upper of roof is the inducing point of surrounding instability. Thus, the stability of surrounding rock is related to coal seam angle, shear surface length, and physic-mechanical parameters of coal-rock mass. After gateway supporting, the plastic breaking zone of surrounding rock along the inclination of coal seam is less, and the amount of roof separation is kept in reasonable range. Moreover, the improvement of two-side supporting strength is beneficial to the stability of gateway surrounding rock.
出处
《采矿与安全工程学报》
EI
北大核心
2012年第5期637-643,共7页
Journal of Mining & Safety Engineering
基金
国家自然科学基金项目(50874037
51174078)
关键词
大倾角煤层
回采巷道
失稳方程
数值计算
相似模拟
现场监测
high-pitched seam
gateway
instability equation
numerical calculation
similar simula-tion
field monitoring
