Mechanical Properties and Failure Mechanism of the Weakly Cemented Overburden in Deep Mining

With increases in the mining depth and area Ordos coal field, failure law of super thick sandstone Zhidan group leads to frequent disasters, such as rock bursts mine earthquakes, which have become a significant issue, restricting large-scale continuous mining. To adequately understand movement mechanism super-thick weakly cemented overburden, promote resources under it, this study analyzes physical mechanical properties, along with microstructural characteristics, overburden Yingpanhao Coal Mine through mechanics tests, scanning electron microscope tests (SEM) hydrolysis experiments. A two-dimensional discrete element model survey region is then built explore temporal spatial evolution laws failure. The results show that, even though poorly strata Cretaceous Zhiluo are weak lithology, their unique mineral composition characteristics give them greater rigidity when thickness reaches certain value. surface subsidence exhibits sudden increase, dynamic disaster range overlying wide deep multi-face was carried out overburden. influence boundary closely related depth, relationships evolve into Boltzmann function Boltzmann–parabolic function, respectively. mode ‘beam–arch shell–half arch shell’, fractures.