夹矸煤层巷道锚杆支护角锚杆倾斜角度的确定及稳定性研究

针对国内某大型矿井工作面顺槽的现场条件,以整体锚固理论为指导,采用理论分析与数值计算相结合方法,研究不同锚杆支护方案下巷道的应力场变化情况.研究结果表明:采用整体锚固能够使巷道围岩形成一个整体锚固带,即锚固应力压缩带,角锚杆不同的倾斜角度会产生不同的整体锚固效果;煤层巷道顶板、两帮及底板由于层状分布而整体性差,在利用锚杆支护时,应采用整体锚固支护技术,以使其形成整体的锚固结构;顶板和两帮的角锚杆随着倾斜角度的增大,巷道锚固体间的缝隙逐渐变小,直至完全成为一个整体;当顶角锚杆、底角锚杆倾斜角度达到一定值时,最大主应力场在巷道周围形成了一个完整的压缩带,即整体锚固,此事如果角度继续增大,锚固效果将逐渐降低.

Determination of Inclination Angle and Stability Study of Bolting in Seams with Dirt Band

Based on the field situation of working face crossheading of one large-scale mine and the whole bolted structure theory,theoretical analysis and numerical calculation are combined to study stress field variation under different supporting plans.The results show that: the whole bolted structure enables the surrounding rocks to form a whole bolted belt,anchoring stress compaction band;different inclination angles of angle anchor have different effects;because of poor integration caused by layer distribution of coal seam roof,two sides,and floor,the whole bolted structure should be used.With the increasing inclination of the angle anchors of roof and two sides,the cracks between the bolted structure decrease gradually until a whole structure appear;when the inclination angles of top and bottom angle anchors attain to a certain value,the maximum principal stress field forms a complete compaction belt,the whole bolted structure,but if the angle increase continues,the supporting effects will drop gradually.