Study on roof deformation characteristics of gob-side entry retained by hydraulic fracturing

In order to explore the deformation characteristics of the roof of the gob-side entry and the top position of the roadside backfill body with hydraulic fracturing main roof, FLAC^3D numerical simulation method is used to simulate the deformation characteristics of gob-side entry and roadside backfill body before and after hydraulic fracturing based on the main roof hydraulic fracturing project of 22104 working face transportations in Liuta Coal Mine.The results show that the roof deformation of gob-side entry increases gradually from the coal wall to the roadside backfilling body, and the deformation at the top of roadside backfilling body also increases gradually from gob-side entry to gob.After main roof hydraulic fracturing, the average roof deformation of gob-side entry decreases from 10.70 mm to 7.23 mm, and the average deformation at the top of the roadside backfilling body decreases from 16.82 mm to 9.13 mm.The deformation of roof of gob-side entry and at the top of the roadside backfilling body both decrease obviously.The field measurement results show that the deformation of the roof deformation of the gob-side entry and the top position of the roadside backfilling body are maintained between 20-25 mm and 60-65 mm, respectively.The successful application of hydraulic fracturing basic roof gob-side entry retaining technology in Liuta Coal Mine provide a certain reference for other similar mines or working faces.