多滚刀顺次作用下岩石破碎模拟及刀间距分析

相邻滚刀刀间距设计是全断面岩石掘进机(TBM)刀盘设计的关键技术之一,刀间距设计的合理与否直接关系到刀盘刀具掘进效率和寿命.刀间距设计不仅与岩石边界条件、刀盘掘进参数及刀具参数有关,而且与刀盘结构相互耦合相互影响,且相邻滚刀之间是一种顺次破碎岩石的过程.基于有限元岩石破碎仿真平台RFPA2D,考虑相邻多滚刀的顺次约束关系,分别以2种典型岩石(泥质粉沙岩和花岗片麻岩)为边界条件,建立多滚刀顺次作用下垂直压入岩石的破碎仿真模型,模拟多滚刀在顺次压入和同时压入岩石的仿真过程,建立了刀间距与岩石破碎能量之间的映射关系,进而建立了多滚刀最优刀间距下顺次角度与岩石破碎能量之间的映射关系,通过此映射关系可以确定滚刀在刀盘上不同位置的最优刀间距和最优的顺次角度,并为下一步滚刀在刀盘盘面上的布置设计提供设计依据.

Numerical simulation of the rock fracture process induced by multi-disc-cutters and cutter spacing design

Spacing design of adjacent cutters is one of the key technologies in the full face rock tunnel boring machine(TBM) cutter head design,which is directly related to the boring efficiency of the TBM cutter head and the cutter tool’s life.Spacing design of adjacent cutters not only is related to the boundary conditions and rock as well as the cutter and cutter parameters of the tunneling parameters,but also couples with the cutter structure interaction;it is a sequential process of broken rock.Based on the finite element simulation platform of rock crushing-Rock Failure Process Analysis(RFPA2D),considering the adjacent multi-cutters sequential constraints,taking two typical rocks(muddy pink sandstone and granite gneiss) as boundary conditions,smoother hob times under the vertical pressure into the rock crushing simulation model were constructed.This simulated how the multi-cutters in the sequential and simultaneous pressure pushed the rock into the simulation process.The mapping between disc cutters spacing and rock fragmentation energy was established,and thereby a mapping between multi-cutters sequential location angle and the energy of rock fragmentation was established during spacing of the optimal cutters.The cutters’ optimal spacing and the optimal sequential angle in a different location can be determined through this mapping,and it can also provide the design basis for the layout design of future cutters.