A review of water rock interaction in underground coal mining: problems and analysis

Underground coal mining has a strong disturbance on surrounding rock strata, causing inevitable water inflow into mined spaces, which seriously affects safety production. Mine water disaster is regarded as one of the most critical problems in coal mining and, thus, has been a research hotspot in coal mining. This review focuses on water-rock interaction (WRI) in underground coal mining and lists the main issues of WRI. The corresponding analysis methods (laboratory testing and numerical simulation) of WRI in coal mining are discussed. The research related to WRI in underground coal mining mainly focuses on the water inrush form roof and floor, water weakening of roadway surrounding rock (coal pillar), water inrush from fault or collapse column, and the utilization of abandoned mines. Laboratory test (on intact rock mass, fractured rock mass, and broken rock mass) approaches and numerical simulation methods of WRI are summarized, and their advantages and limitations are discussed. Based on the WRI problems and analysis in underground coal mining, future works on laboratory testing and numerical simulation are prospected.