大采高工作面切顶留巷支护参数优化研究

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

针对大采高开采条件下煤层较厚,在切顶留巷技术现场实施过程中,常遭受矿压显现剧烈、巷道变形严重,给留设巷道的顶板支护带来难题,以柠条塔煤矿大采高S1201工作面为工程背景,采用恒阻大变形锚索作为巷道顶板的关键支护设备,在现场进行了5种不同支护方案的对比试验,通过对比不同支护方案下的顶板下沉规律,得到了有效的切顶留巷顶板支护参数。结果表明:S1201区段运输平巷有效且经济的架后补强支护方式是在原支护的基础上,于切缝侧补强1排恒阻锚索,锚索长度增加至9 000 mm,排距2 000 mm,除此之外补打3列普通锚索,普通锚索间距1 500 mm,普通锚索间去掉W钢带。该工程的成功应用为国内厚煤层切顶留巷技术提供了借鉴。

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 deformation of the roadway are often encountered in the process of the roof cutting entry retaining,which brings great diffi- culties to the roof support design. Taking the large mining height S1201 working face of Ningtiaota Coal Mine as the engineering back-ground,with constant resistance and large deformation of roadway roof anchor as the support 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 S1201 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, three 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.