Surrounding rock support technology of extra thick coal seam roadway under the influence of mining

In view of the difficulty of surrounding rock support in the extra thick coal seam roadway affected by twice mining in Suancigou Coal Mine, the deformation and failure law of surrounding rock in the extra thick coal seam roadway under the influence of mining was analyzed by means of theoretical analysis, numerical simulation and engineering practice. The staged supporting technology for the roadway surrounding rock of extra-thick coal seam under the influence of mining was proposed, and the engineering practice was carried out. The results show that under the influence of primary mining, the plastic zone of surrounding rock of roadway presents a trend of “enlargement and stabilization”, which is mainly manifested as lag effect. Outside 300 m behind the working face, the plastic zone remains unchanged. Under the influence of secondary mining, the plastic zone of surrounding rock of roadway presents a trend of “reduction-stabilization”, and the effect is larger within 30 m of the working face, and then gradually tends to be stable. And the surrounding rock of the test roadway can maintain stability.