Directional Destress with Tension Blasting in Coal Mines

In China, engineering geological disasters are frequently encountered in the underground mining sites where room and pillar method is used. This paper presents a novel method for developing the gateway tunnel without any excavation using directional tension blasting (DTB) in the mine panels. The mining-induced stress transfer will be blocked by cutting the roof stratum with a slit produced by DTB. The method has the following advantages: 1) forming the gateway tunnel without any excavation work; 2) de-stress, and 3) reducing the number of the pillars significantly. The DTB has been applied in many giant coal mining corporations in China and proved to be very helpful in 1) increase in productivity and reduction in costs dramatically, and 2) elimination of engineering geological disasters induced by the coal pillar and mining stress.