Abstract: The soil characteristics in TBM cutterhead excavating working，the TBM cutterhead torque and total thrust excavating were mainly analyzed.Based on soil characteristics of ion-absorbed rare earth，the TBM cutterhead structure model was established，and the mathematic model of cutterhead torque and total thrust excavating were established according to the structural model.Finally，the experimental model of cutterhead torque and total thrust excavating was established in the light of the cutterhead structure model.Through studies on the changing law of cutterhead torque and total thrust excavating of TBM in ionic rare earth mineral soil，the impact of different structural parameters on the cutterhead torque and cutter total thrust excavating was obtained.The results showed that the resulting of cutterhead torque and total thrust excavating from the tests differ from that of the mathematic model by less than 10% only，which verified the correctness of the mathematical model.The cutter aperture ratio and the angle between the front and the lateral are important parameters of affecting the torque and total thrust excavating through mathematical model.Finally the appropriate cutterhead structural parameters were summarized by analyzing experimental results.

Key words: Thrust boring machine（TBM) , Ionic rare earth, Total thrust excavating, Cutterhead torque