Affection on the Deformation of Surrounding Rock of Railway During Bottom-Slice Mining with Sublevel Caving

摘要

Based on the geological condition of low-stress zone railway of bottom-slice and fully mechanized coal face with sublevel caving of Yangcun Coal Mine, Yima Coal Group, China, observation stations were set up in railway in front of the coal face. With multipoint-displacement meter and nondestructive detection meter of ultrasonic-wave, the paper systematically studied on deformation quantity, deformation speed and the range of loose zone of railway during mining coal face. The results show that, the deformation quantity of railway laid in gob during mining coal face is 200-300mm which the value is in the range of permission deformation for rigidity ladder-shaped supports. The dimension of loose zone of surrounding rock of railway beyond mining affected zone is 2.9m, while the dimension in mining affected zone is more than 3. 8m. Therefore, strata behavior of low-stress zone railway during mining coal face is gentler and conventional support can meet requirement on railway service. The conclusions have a definite reference for gateway layout in the coal face.