采动影响下软弱底板小煤柱巷道底鼓机理及协同控制技术OA

To address floor heave issue in small coal pillar roadways with weak floor strata under mining-induced disturbances,which restricts the safe and efficient production of coal mines,this paper presents a combined research method of theoretical analysis,numerical simulation and field tests to investigate the coupling mechanism between weak floor strata and mining-induced disturbances,reveals the floor heave mechanism of such roadways and establishes a prevention and control technology system.The results indicate that the core causes of floor heave in the 2103 return airway include the low compressive strength of the floor rock mass,the instability of the small coal pillar caused by mining,and the stress concentration caused by the transfer of the weight of the overlying strata in the goaf to the solid coal side.To mitigate the above coupling disaster-causing factors,a"blasting pressure relief+small coal pillar grouting reinforcement+concrete pouring"coordinated control technology is proposed.The coordinated control technology achieves precise control of floor heave by forming directional fractures through blasting pressure relief to release surface stress,blocking stress transmission through grouting reinforcement of the small coal pillar and constructing a"coal pillar-floor"coordinated load-bearing structure,and enhancing the floor stiffness to suppress deformation through concrete pouring.Field industrial tests show that the floor heave at the treated area decreased by 94.2％compared with the untreated area,verifying the reliability of the scheme.The research conclusions provide theoretical basis and engineering examples for the prevention and control of floor heave in similar roadways.