Theory And Application Of Disc Cutter Life Prediction Of Full Face Rock Tunnel Boring Machine

Full face rock tunnel boring machine(TBM)is a commonly used mechanical equipment for underground tunnel excavation,and the rock breaking process mainly depends on disc cutters installed on the cutterhead.The cutters work in harsh environment and are easy to wear,thus require frequent replacement and needs TBM to shut-down.The replacement time of the worn cutters costs 1/4 of the whole project period,and the cost of the disc cutters is also about 1/4 of the whole project cost.Due to the fact that there is no practical application of on-line monitoring of the wear of cutters,it is of great importance to study cutter wear to reduce cutter consumption and to reduce cutter changing time.In this paper,a prediction method for disc cutter wear is proposed by analyzing the rock breaking movement of disc cutters.The specific research contents are as follows:(1)With the Microanalysis of rock breaking movement of disc cutters,disc cutters are deviede into two categories according to the different trajectories in rock breaking.The center cutters and face cutters are classified as a class of wear analysis whereas edge cutters and transition cutters are classified as another class.(2)For center cutters and face cutters,a concept of arc length wear coefficient is proposed.For edge cutters and transition cutters,a concept of Wear coefficient of spiral line is presented.Based on the above two wear class in TBM,analytical models for the both classes are established,which provides theoretical support for the prediction of wear and its life prediction analysis on different installation position of cutters(3)According to the established analytical models,the wear and replacement data of disc cutters collected from Qinling tunnel construction are applied to verify the above models.