Overburden failure and water-sand mixture outburst conditions of weakly consolidated overlying strata in Dananhu No.7 coal mine.

This study presents a case of weakly consolidated strata developed in Dananhu No.7 coal mine. Using a combination of numerical simulation, field measurement comparison, and the critical hydraulic gradient criterion, we investigate the overburden failure and the risk possibility of water-sand mixture inrush during excavation.