Optimization research on supporting parameters of roof cutting entry retaining with large mining height face

In view of the thick coal seam under the condition of large mining height, the problems such as the severe pressure of the mine and the serious deformat ion of the roadway are often encountered in the process of the roof cutting entry retaining, which brings great difficulties to the roof support design. Taking the large min ing height S1201 working face of Ningtiaota Coal Mine as the engineering background, with constant resistance and large deformation of roadway roof anchor as the su pport of key equipment, the different support schemes comparison are tested in the field. By comparing the law of roof subsidence under different support schemes, the paper find an effective roof support parameters of roof cutting entry retaining. The results provide an effective and economical reinforcement after support method for S 1201 haulage roadway of zone. On the basis of the original support, a row of constant resistance anchor rope is strengthened at the cutting seam side. In addition, thre e columns of ordinary anchor rope are added and the length of the anchor rope is increased to 9 000 mm, the row spacing is 2 000 mm, the normal anchor rope spacing is 1 500 mm, and the W steel strip is removed between the ordinary anchor cables. The successful application of this project provides a useful reference for roof cutting entry retaining in thick coal seam.