新型重力式竖井连续掘进机滚动截齿破岩机理

Rock breaking mechanism of rolling cutter of new gravity vertical shaft continuous heading machine

为改变竖井掘进方式,提高破岩效率,研发一种新型重力式竖井连续掘进机。采用SolidWorks软件建模,利用HyperMesh和LS-DYNA软件开展有限元分析,模拟不同速度下截齿的滚动、扭转嵌入岩石的动态破岩过程;通过现场重力式竖井连续掘进机滚动截齿破混凝土相似试验,进行动态下截齿破岩试验以探究截齿破岩机理。结果表明:截齿在最优滚筒转动速度为30 r/min下破岩比能较低,可加大岩石内部应力变化,削弱岩石内部结构承载力,增加岩石裂缝产生和扩张范围,最终岩石发生凹陷性破坏。再结合重力式竖井连续掘进机滚动截齿破混凝土相似试验,分析在相同时间内混凝土破坏程度,证明最优滚筒转动速度为30 r/min,验证数值模拟的准确性。新型重力式竖井连续掘进机的研发可革新现有竖井掘进方式,尤其对卵砾石、冻土、中低强度岩石等地层具有良好的适应性。

To change shaft excavation mode and improve rock breaking efficiency, a new type of gravity shaft continuous heading machine was developed. Dynamic rock breaking process of pick rolling and torsion embedded in rock at different speeds was simulated with SolidWorks for modeling and HyperMesh and LS-DYNA for finite element analysis. Through similar concrete breaking test of rolling cutter of gravity shaft continuous heading machine, the rock breaking test of pick under dynamic condition was carried out to explore rock breaking mechanism. The results have shown that rock breaking specific energy of the cutter is lower when optimal rotation speed of the drum is 30 r/min, which can increase the change of internal stress in the rock, weaken bearing capacity of rock internal structure, increase generation and expansion range of rock cracks, and finally lead to the rock depression failure. Combined with similar concrete breaking test of rolling cutter of gravity shaft continuous heading machine, the damage degree of concrete in the same time was analyzed, which has proved that the optimal drum rotation speed is 30 r/min, which can verify the accuracy of numerical simulation. The research and development of new gravity vertical shaft continuous tunneling can innovate existing shaft excavation methods, especially for gravel, frozen soil, medium and low strength rock strata.