High-strength Combined Supporting Technology of Coal Roadway with Large Thickness and Thin-Layered Composite Roof

To solve the problem of large deformation of the roadway with large thickness and thin-layered composite roof in the 53151 haulage roadway of Zhaozhuang Coal Mine, combining with field investigation, laboratory experiments, theoretical analysis and physical experiments, the main causes of deformation and failure of the roadway are analyzed, including the thickness of stratification of composite roof, content of expansive minerals, unreasonable supporting parameters of supporting body and supporting surface components. Based on the theory of combination beam and suspension, the “high-strength combined support technology” is proposed, and the support parameters are optimized. The results of numerical simulation and field practice show that compared with the original support scheme, the deformation amount of roof and floor and two sides of roadway in the optimized supporting scheme are reduced by more than 80% and 63% respectively, and good surrounding rock control effect is achieved.