Strata movement and stress evolution when mining two ...
Sep 01, 2019· 1. Introduction. Deep coal seams usually bear a higher ground stress and a higher gas content than shallow coal seams, which increases the risk of gas outburst, and most coal seams deeper than 500 m are prone to dangerous gas release,, .To reduce the risk of explosion, the development of a safety coal seam as a measure of protection is a method that is widely used all over the world.