Research on rational width of entry protection coal-pillar in large mining height workface

For the study on the problems of rational width of entry protection coal-pillar, according to the gateway of 6103 mining face with large mining heitht in Kanghe mine, through theoretical calculation and numerical simulation, rational width of entry protection coal-pillar was educed, and its feasibility was demonstrated through engineering practice, which provided some theoretical references for preserving reasonable coal-pillar for the similar coalface with large mining heitht.