深部巷道预应力协同支护数值分析

Numerical Analysis of Theory of Pre-Stress Synergetic Support in Deep Mine Roadway

为了改善深部巷道围岩稳定性难以控制这一现状,提出了锚杆、锚索预应力协同支护思想.采用数值模拟的方法对巷道预应力协同支护进行计算与分析.结果表明:在现有的实际支护条件下,高强锚杆需施加40 kN及以上的预应力才能与锚索100 kN以上的预应力相协同;当锚杆、锚索的预应力产生协同作用时,对深部巷道的支护效果明显,巷道周边的应力集中区范围明显减小,应力分布趋于均匀;同时锚杆、锚索的平均利用率都达到0.5以上,且它们之间相差不大,充分发挥了高强锚杆、锚索的受力特性,使锚杆、锚索协同工作,避免了单独依次受力.故应该采用协同支护理论作为深部巷道工程支护设计的理论依据.

In order to improve the actuality that the stability of surrounding rocks in deep roadway is difficult to control,we put forward the idea of bolt and cable＇s pre-stressing synergetic support.Using numerical simulation,we calculated and analyzed the deep roadway supported based on this idea.The results show that,under the current support condition,high-strength bolts must be used with a pre-stressing force greater than 40 kN to cooperate with cables with more than100 kN pre-stressing force.When the pre-stressing force of bolt and cable have a synergistic function,the deep roadway will have an apparent support effect,for example,the stress concentration area surrounding the roadway decreases significantly,and the stress distribution tends to be more uniform.The average utilization rate between bolt and cable has only a little difference and both of them are greater than 0.5,making the mechanical properties of bolts and cables give fully play,avoiding the bolts and cables working separately.So we suggest that the idea of pre-stressing synergetic support can be used as a theoretical foundation for the roadway support design.