断层对U型钢支架承载性能影响规律研究

Research on bearing capacity of U-shape steel frame under the influence of fault

为了分析断层对U型钢支架承载性能的影响规律,基于断层参数和支架偏载对其承载能力的作用,以顾北煤矿北一(6-2)上山采区6煤底板专用回风巷为工程实例,采用现场调研、数值计算与工业性试验方法,研究了断层法距、倾角和位置对支架载荷的影响以及偏载支架的承载能力.结果表明:随法距增大,支架上最大弯矩先后在左肩角、左帮出现,之后在两帮出现,并在巷道与断层法距5m时取得最大值3.664MN·m;断层倾角为45°和60°时,支架弯矩分别取得最小和最大值;断层位于巷道顶板时支架弯矩取得最小值0.193 MN·m,断层越靠近底板对支架承载越为不利,支架顶梁与棚腿相比受断层位置变化影响较小;支架抗顶压能力较强,拱顶偏载荷载与均布荷载比值为1.0~2.0时有利于整体承载,肩部偏载对支架最为不利;拱顶偏载较小时,锁棚锚杆(索)的增加反而降低架棚承载能力.

In order to analyze the bearing capacity of U-shape steel frame under the influence of fault,based on the parameters of the fault and eccentric load of U-shape steel frame,the return airways of No.6 coal in north 1（6-2）raise panel in Gubei was taken as an engineering example.By utilizing in-situ investigation,numerical simulation,and industrial experiment,the bearing capacity of U-shape steel frame under different normal distance,dips and location of the fault were studied.The results show that with the increasing of the normal distance,the maximum bending moment on the support appeared successively at the left shoulder angle and left side,and then appeared at the two sides of the roadway.When the normal distance between the roadway and the fault is 5 m,the bending moment reached the maximum value 3.664 MN·m.When the dip is 45°and 60°,the minimum and maximum bending moment values reached respectively.When the fault was located in the roof of the roadway,the bending mo-ment of the support reaches the minimum value 0.193 MN ·m.The nearer the fault was to the bottom,the more unfavorable for bearing capacity.Compared with booth lag,roof beam was less affected by the variation of fault location.The support had stronger resistance to roof pressure.It was conductive to the overall bearing capacity when the ratio of eccentric load on vault to uniform load was1.0—2.0.Eccentric load on spandrel was the worst for support.With the increase of bolts,the bearing capacity of support decreases when the eccentric load on vault is low.