矩形巷道缓倾斜煤层锚杆支护效果数值模拟分析

Numerical simulation analysis of bolt supporting effect in gently inclined coal seam of rectangular roadway

为分析浅埋深矩形巷道在倾斜煤层中锚杆支护效果,采用数值模拟的方法进行研究。首先设计了锚杆支护方案,并针对城兰矿22031工作面的地质采矿条件建立数值模型,模拟巷道长20 m、高3 m、宽4 m的围岩应力、塑性区和位移量的变化情况。从模拟结果可以看出施加锚杆后,巷道表面不出现拉破坏,仅出现剪切破坏,巷道顶板、底板及两帮中部最大主应力最小;锚杆支护后围岩破坏以顶板、底板、两帮表面中部最严重,特别是顶板和右帮;巷道顶板和底板破坏延伸距离相似,但顶板破坏范围大于底板;锚杆支护后矩形巷道两帮和顶板位移量较大,底板位移量非常小。综合分析可见,虽然锚杆支护对巷道变形控制起到作用,但变形量仍很大,锚杆支护对巷道破坏产生较好抑制作用,但并未达到控制巷道破坏的目的。

In order to analyze the effect of bolt support in inclined coal seam of shallow and deep rectangular roadway,numerical simulation method was used to study.Firstly,the bolt support scheme was designed,and a numerical model was established according to the geological and mining conditions of the 20231 working face in Chenglan Mine.The stress,plastic zone and displacement of surrounding rock with a length of 20 m,a height of 3 m and a width of 4 m were simulated.From the simulation results,it can be seen that there was no tension failure on the roadway surface,but only shear failure,and the maximum principal stress in the roof,floor and the middle of the two sides was the smallest;the surrounding rock failure after bolt support was the most serious in the middle of the roof,floor and two sides,especially in the roof and the right side of the roadway;The extension distance was similar,but the roof damage area was larger than the floor;the displacement of both sides and roof of rectangular roadway was larger after bolt support,and the displacement of floor was very small.Fully mechanized caving analysis showed that although bolt support played a great role in controlling the deformation of roadway,the deformation was still very large,the bolt support with inhibition effect on the roadway damage,but not achieving the goal of controlling the roadway damage.