Overall Disc Cutters Layout's Optimization Of Tunnel Boring Machine

TBM(Tunneling Boring Machine)is a highly automatic large-scale tunnel drivage machinery equipment,which has a great advantage over ordinary mining method especially for big-long tunnel.These years,tunnel projects implemented by TBM are increasingly growing in quantity,such as mountain railway,subway tunnel,undersea tunnel,and large water project,etc.So far,the disc cutter on TBM devices often face with seriously destruction,frequently change,and other abnormal damages.Therefore,based on deep research of the rock breaking mechanism,force analysis,and the cutterhead layout of TBM disc cutter,this paper proposed an integrated disc cutter' layout design method,main content of which are as follows:(1)Emphatically research on the force of disc cutters which are placed near the center of the cutter-head,and through this research,the unbalanced force model of center disk cutter is proposed.Based on the physical truth of the disc cutter cutting rock and the force analysis of the original CSM model,the improved CSM model is proposed.The NX-Nastran software is used to analysis the disc cutter's force and its strength is checked.Then the calculation of original CSM mode,other existed force model in domestic and foreign,and the experimental data are compared,the improved CSM model has been verified more accurate.Based on the reason of unbalanced force existed,the new center disk cutter layout method is proposed.(2)A generalized layout design method is proposed for front disc cutter.Based on the basic principle of TBM disc cutter layout and analysis of spiral cutter decorating rule,this paper described a brand new layout design method of disk cutter' layout design by spiral.Under theory of making minimum difference in rock-broken volume,we established a multi-objective optimization model through two step optimizing method of polar radius and angle.Then genetic algorithm is used to make further optimization,and finally NSGA-II algorithm is adopted for multi-objective optimization in polar angle.Taking TB880 E disc cutter as a calculating example to analysis the layout optimization result,in contrast of the original cutter layout decorating method,the unbalanced radial force and capsizing moment of cutter have reduced.Rock broken variance of disc cutter also decreased apparently to a large extent,which can be beneficial to balance the damage of front disc cutter.The integral layout centroid of disc cutter also shows closer proximity with the cutter-head center.(3)The edge cutter's layout design method is proposed.Based on the summary of principle of TBM disk cutter layout,and combined the disk cutter layout design by spiral,objective optimization model of the edge disk cutter layout for the Wear difference minimization is established.Using step by step optimization design method to design the polar radius and oblique angle of every disk cutter.Firstly,optimizing the polar radius and oblique angle of edge disk cutter,and then using the NSGA-II algorithm to optimize its polar angle.In this paper,the TB880 E model's cutter-head is used for example to analysis and redesign its layout of edge cutters.Then compared the performance parameters with original disk cutter layout: Unbalanced radial force,cutter overturning moment and edge cutter wear variance have all decreased;The mass center of all cutters after redesign,is more close to the geometric center of the cutter-head.