Physical simulation modeling of roof water inrush in underwater mining

A physical model was used to simulate high-pressure water inrush during underwater mining. The model was constructed from parameters from the Sanshandao mine in Shandong province. An acoustic emission instrument (PCI-2) was used to locate crack development by observing emissions that occurred during the experiment. As the isolation layer in the model was excavated to 100 mm water inrush occurred with development of microscopic cracks that were monitored by stereo-microscope. Using microscopic measurements with image analysis software the average crack width was determined to be 0.08 mm with an inclination of the upper cracks of 32.26 degrees. Observation of how the micro-cracks developed and statistical analysis of model deformation allowed the development of a comprehensive understanding of the mechanism by which water inrush, caused by seepage flow through roof fractures, occurs.