Study on the Mechanical Environment and Adaptability of Fillings beside Non-pillar Mining Roadway

Through the analysis and research on the overburden movement and rock strata breaking rule of gob-side entry with non-pillar mining, it was known that with the advance of the stope working face, the masonry blocks formed by the fracture of the old roof beams were hinged together to form an "arch like" structure. At the same time, it was pointed out that the control object of the surrounding rock with non-pillar mining was the rock beam which had obvious influence on the lateral support pressure of the stope in "arch like" structure, the control idea of "given deformation" was adopted to control the above rock beam; the mechanical model of the surrounding rock structure of gob-side entry with non-pillar mining was established, which was jointly supported by the solid coal seam of the gob-side entry, the fillings beside roadway and the gangue of the gob. Taking 1706 east working face of Zhaoguan Coal Mine as the engineering research object, the theoretical calculation of working resistance and coordinated deformation of the fillings beside roadway was carried out. According to the above calculation results, orthogonal test method was adopted to study the proportion of filling materials and the mechanical characteristics of fillings was analyzed, which obtained a new type of fillings beside roadway suitable for deformation of gob-side entry with non-pillar mining and having good bearing performance. The field measurement results show that the new type of fillings beside roadway can achieve the expected effect of surrounding rock control in non-pillar mining, which provides a new way for safe and green mining of coal mine.