TBM滚刀破岩效果及新型刀具的应用研究

Research on rock-breaking effect of TBM hob and application of new type cutter

TBM滚刀磨损是影响TBM掘进效率和施工成本的重要因素,不同刀刃刃形的破岩效率和磨损均会有所不同。本文对楔形弧刃滚刀的破岩机理进行了分析,建立了滚刀法向切削力计算模型,分析了滚刀刀刃角对法向切削力的影响;继而设计了3种不同刀间距、3种不同刃形滚刀,并进行了室内滚刀破岩试验。试验结果表明:刀间距15 mm为合理刀间距;尖刃滚刀最易磨损,齿刃比弧刃滚刀破岩效果好,破岩效率相对较高且耐磨损。结合工程现场实际情况,研发了一种新型齿刃楔形刀具,并应用到工程现场TBM斜井掘进。应用情况表明:新型齿刃楔形刀具比两种常规刀具的磨损量减少20%,刀具寿命有所提高。新型齿刃楔形刀具的研发和成功应用,解决了斜井TBM掘进刀具的较大磨损和频繁更换问题,为TBM长距离斜井掘进提供了技术支持,缩短了掘进工期,节约了施工成本。

TBM hob wear is an important factor that affects the TBM tunneling efficiency and construction cost.Different blade types differ in rock breaking efficiency and wear.By analyzing the rock-breaking mechanism of the arc blade wedged hob,this study established the calculation model of hob normal cutting,and analyzed the influence of hob edge angle on normal cutting force.This study then designed three kinds of hobs with different cutter spacing and three types of hobs with different blade for rock breaking tests in laboratory.Results show that the reasonable cutter spacing is 15mm,sharp blade is prone to be worn,the tooth-like blade,which has higher rock breaking efficiency and wear resistance,is better than arc blade.Combined with the actual situation of the project site,a new hob with wedgeshaped blade is developed,which are applied to inclined shaft TBM tunneling at engineering site.Results show that the wear rate of the new wedge-shaped hob is 20%less than that of the conventional ones,and the service life of former is longer than that of latter.Under the same geological conditions,new wedge-shaped hob can reduce the number of hobs consumption and improve efficiency of tunnelling.The development and application of the new type successfully solved the problems of hob wear and frequent replacement of hobs in the TBM inclined shaft excavation.It can provide technical support for TBM long distance inclined shaft driving,which not only shortened the construction period,but also saved the construction cost.