Study on development law of water-conducting fault zone in deep gently inclined double coal seam mining

Abstract

In order to study the development characteristics of water-conducting fracture zone in deep-buried gently inclined multi-coal seam mining, taking the overlapping mining area of 2-1 coal and 2-2 coal in Shicaocun Coal Mine as the research object, through the underground uphole water injection test and numerical simulation method, the overlying rock failure and the development characteristics of water-conducting fracture zone are studied. The results show that under the same geological and mining conditions, the development process of water-conducting fracture zone of overlying 2-1 coal with 1.8 m mining thickness and 2-2 coal mining thickness of 3.4 m can be divided into occurrence and slow increase stage, sudden increase stage and stable stage. However, the development rate of 2-2 coal water-conducting fracture zone is higher than that of 2-1 coal water-conducting fracture zone. Under the condition that the distance between 2-1 coal and 2-2 coal seam is 11 m, the height of compound water-conducting fracture zone produced by 2-2 coal mining is greater than that of 2-1 coal mining. After comprehensive analysis, it is determined that the development height of water diversion fracture zone in repeated goaf of multiple coal seams in Shicaocun Coal Mine is 49.6 m.

Keywords

• deep buried gently inclined coal seam
• multi-seam mining
• numerical simulation
• underground uphole test
• water-conducting fracture zone