Abstract: In order to improve the extraction rate of strip mining,the method of coal pillar reinforcement and reducing the width of pillar is proposed.By analyzing numerical simulation,it is revealed that the strip coal pillar can optimize the strip mining and the coal pillar reinforcement.The results show that the coal pillar reinforcement can reduce the width of remaining coal pillar and improve recovery rate of strip mining.Combined with special geological and mining conditions of a certain coal mine in China and the thought of coal pillar reinforcement with roadway shores,the joint reinforcement technology of shed and wood crib was used in the test area with the width and interval of reinforcement bodies composed of shed and wood crib 1.5 m and 2m separately.Analysis on data of the underground displacement monitoring of coal pillar and the surface settlement monitoring indicated that the maximum vertical displacement of underground pillar reinforcement body is 361 mm,and the maximum subsidence of surface is 217 mm.Coal pillar reinforcement can effectively prevent from the destruction of the coal wall,control ground surface deformation,and ensure the safety of the building.So,the thought of coal pillar reinforcement with roadway shore can provide important way and reference for coal mining under buildings.

Key words: Mining subsidence, Strip mining, Coal pillar reinforcement with roadway shores, Joint reinforcement technology of shed and wood crib, Monitoring data