Abstract:In order to reduce the health risk of equipment due to excessive cutterhead torque fluctuation, the overload and fluctuation of cutterhead torque need to be dynamically suppressed. The dynamic control thresholds of tunneling parameters under the constraint of tunneling efficiency control law is explicitly derived to reveal the suppression strategy on the basis of decoupling the network influence mechanism among geological parameters, tunneling parameters and rock mass boreability through the combinational two-factor analysis. The results show that: the combinational two-factor analysis can learn the low-dimensional characteristics of the mechanism of differential interaction within the rock mass boreability control factors, the multigroup monotonicity analysis and the elliptic conic envelope model can explain the influence mechanism of the factors on boreability. The elliptic conic envelope model can accurately determine the overload risk of cutterhead torque in the form of analytical model in multiple stratum. In the risk management and control task against the tunneling parameters fluctuation and the key components damage of shield, the dynamic control method for shield tunneling parameter thresholds based on decoupling analysis of boreability can provide explicit decision instructions and the control chain of fast command response. The output of the instruction layer of the control method is interpretable for the two-dimensional projection of the elliptic conic envelope equation can be transformed into a dynamic threshold model of tunneling speed with the cutterhead torque thresholds as the control goal under the constraint of tunneling efficiency control law. The command logic of the application layer is prior-determined single factor control, which can not only respond to dynamic instructions quickly, but also enhance the steady state of tunneling parameters.