Mechanical behaviour and seepage characteristics of coal under the loading path of roadway excavation and coal mining

The mechanical behaviour and seepage characteristics of coal under the mining engineering disturbance are great significance to prevent gas disasters. Based on geological conditions No. 12 mine China Pingdingshan Mining Group, experiments stress path roadway excavation were carried out. experimental result shows that: in fracture zone is most strongly affected by excavation. samples showed obvious expansion phenomenon, their cracks complex. They formed effective permeability before peak strength, was largest; less excavation, after strength. Their smaller than zone; original rock only mining, its crack growth degree lowest. stable residual strength stage, smallest. In practical engineering, special attention should be paid sudden gushing caused increase seam permeability, which will cause disaster.