Research on Ground Ecological Protection Technology for Large Area Filling Mining

In order to solve the problems of large area ground subsidence and limited discharge of mined gangue caused by the traditional collapse method for roof management, this research takes Xingdong Mine as the engineering background, comprehensively uses methods of theoretical analysis and constructing mathematical calculation model, based on the interaction mechanism between rock layer control and deformation and theories of continuous curved beams and so on, different elastic gradient filling methods are explored and adopted to conduct roof management, and a filling body support structure of "weak-strong-weak" is proposed, through the elastic modulus gradient design from 50 MPa in the strong filling area to 30 MPa in the weak filling area, the large area surface sedimentation caused by non-uniform deformation at the boundary is effectively alleviated; Processes such as poor coagulation modified filling, regional protective filling coal mining, mining selection filling and retention filling mining and others are implemented to repair associated ground fissures in subsidence basins in sequence. The practice shows that surface deformation can be controlled at level I, achieving coal mining without relocating villages, eliminating downhole safety hidden dangers, processing over 1 million tons of gangue annually, reducing carbon emissions by over 180 000 tons, and obtaining significant benefits.