TBM扩挖方式及其对比分析

Comparison and Analysis of Tunnel Boring Machine Overcutting Methods

为解决TBM在软弱围岩和断层破碎带中掘进的适应性以及有效应对收敛变形造成的侵限和卡机问题,结合秦岭隧道、大瑞铁路等TBM应用案例,通过对液压式扩挖刀、边滚刀外移、预留扩挖刀箱、主驱动偏心设计和更换刀盘边块5种针对性设计方案进行对比,得出不同扩挖方式的应用特点及适用机型。主要研究结论如下:1)液压式扩挖刀可单独适用,适用于短距离扩挖,其他4种方式均适用于长距离扩挖;2)在半径方向扩挖量大于50 mm时,边刀外移必须和刀盘抬升同时使用;3)半径方向最大扩挖量不宜超过100 mm,更大的扩挖必须通过更换边块方式解决;4)随着TBM技术的发展,半径方向100 mm以上的便捷扩挖方式仍是下一步研究的方向。

To improve the applicability of tunnel boring machine(TBM)excavation in the weak surrounding rock and fault fracture zone and effectively cope with the problems caused by the convergence and deformation of the surrounding rock,such as beyond-limit deformation and TBM jamming,five targeted overcutting designs,namely,hydraulic over cutter,outward movement of gauge disc cutter,reserved over cutter housing,main drive eccentricity design,and changing cutterhead side block are compared based on the application of TBMs in Qinling Tunnel,Dali-Ruili Railway and other projects,and the application characteristics,and applicable TBM types of different overcutting methods are concluded.It is concluded from the above research that:(1)the hydraulic over cutter can be used alone and is suitable for short-distance overcutting,whereas the other four methods are all suitable for long-distance overcutting;(2)when the overcutting volume needs to be greater than 50 mm in the radial direction,both the outward movement of gauge disc cutter and the lifting of cutterhead must be conducted simultaneously;(3)the maximum overcutting volume in the radial direction shall not exceed 100 mm,and a larger overcutting volume must be achieved by changing cutterhead side blocks;and(4)with the development of TBM technology,the easier overcutting method with an overcutting volume of more than 100 mm in the radius direction should be further studied in the future.