Abstract This paper gives a detailed analysis of the mechanical properties of a soil mass cut by a cutterhead in the process of shield driving and a method for calculating the cutter wear of a slurry shield that is deeply buried in sandy strata. The loading features of a single cutter are obtained by the solution of a soil shear failure equilibrium equation, and then the theoretical torque of the whole cutterhead is given by way of summation. The concept of a cutterhead wear coefficient is proposed based on the comparison of the theoretical torque and the measured torque. Application to a specific case indicates that the shield can keep driving if the cutter wear coefficient is around 0.8, while the torque tends to decline rapidly if the coefficient is lower than 0.75, and the cutting tools must be changed if the coefficient is lower than 0.5. After changing the cutting tools in the above mentioned project, the calculated theoretical torque is approximate to the measured torque, which further validates the reliability of the research method presented in this paper.
Abstract：
This paper gives a detailed analysis of the mechanical properties of a soil mass cut by a cutterhead in the process of shield driving and a method for calculating the cutter wear of a slurry shield that is deeply buried in sandy strata. The loading features of a single cutter are obtained by the solution of a soil shear failure equilibrium equation, and then the theoretical torque of the whole cutterhead is given by way of summation. The concept of a cutterhead wear coefficient is proposed based on the comparison of the theoretical torque and the measured torque. Application to a specific case indicates that the shield can keep driving if the cutter wear coefficient is around 0.8, while the torque tends to decline rapidly if the coefficient is lower than 0.75, and the cutting tools must be changed if the coefficient is lower than 0.5. After changing the cutting tools in the above mentioned project, the calculated theoretical torque is approximate to the measured torque, which further validates the reliability of the research method presented in this paper.
2016, Vol. 53 