薄基岩强风化厚松散层下巷道掘进与支护技术

Excavation and Support Technology of Roadway under Thick Loose Layer with Thin Bedrock and Strong Weathering

以神东锦界煤矿浅埋深、薄基岩、强风化带及厚松散覆盖层下典型薄基岩强风化厚松散层极复杂条件巷道掘进为工程背景,基于煤岩体X射线实验成分特性分析成果,结合室内多种含水状态煤岩试样的单轴压缩作用,探究了厚松散层强风化薄基岩遇水物理力学性质弱化效果,从而提出了31410工作面“超前探放水+锚索架棚双重支护+小断面切眼掘进+及时顶板离层监测”掘进支护一体化方案。该项技术应用于锦界煤矿四盘区薄基岩特殊条件下巷道掘进,实现了强风化、富含水厚松散层下极限基岩厚度2 m的多重复杂条件下的巷道安全、高效、经济的掘进工作,为解决同等地质条件下的工程实际问题提出有效的理论依据和技术方案。

The engineering background is the tunnel excavation under the extremely complex conditions of shallow buried depth,thin bedrock,strong weathering zone and thick loose overburden under typical thin bedrock,strong weathering and thick loose overburden in Jinjie coal mine,Shendong,based on the results of X-ray experimental component analysis of coal and rock mass,and combined with the uniaxial compression of various water-bearing coal and rock samples in the laboratory,the weakening effect of physical and mechanical properties of strong weathered thin bedrock in thick unconsolidated bed when exposed to water is studied,therefore,the integrated scheme of"advance water exploration and drainage+double support with anchor cable and scaffolding+small section openoff cut tunneling+timely roof separation monitoring"is put forward in 31410 working face.The technology is applied to the roadway excavation under the special conditions of thin bedrock in the No.4 panel of Jinjie coal mine,it has realized the safe,efficient and economical tunneling work under the multiple complex conditions of the limit bedrock thickness of 2 m under the strong weathering and the rich water thick loose layer,the effective theoretical basis and technical scheme are put forward to solve the practical engineering problems under the same geological conditions.