Two movements of particular interest are the creation of gaps above coal pillars and falling of standing support elements without apparent damage. A dynamic boundary element program was used to explore movements induced by slip on geologic features removed ...

<p>Pillar design is the first line of defense against rock falls&mdash;the greatest single safety hazard faced by underground coal miners in the United States and abroad. To help advance the state of the art in this fundamental mining science, the National ...

This research has attempted to construct the stress and convergence profiles of the pillar in order to evaluate the ultimate strength, pillar deformation modulus, visco-elastic deformation, and violent failure characteristics during longwall mining. This information ...