Noise Reduction of TBM Big Tunneling Data by Butterworth Filter

The location of a Tunnel Boring Machine (TBM) is prone to external environmental and internal system noise interference. To address TBM vibration characteristics, this study analyzed the sources of excavation data noise, the need for noise reduction, and the methods used, using excavation speed as the prime example. We validated the results through three actual tunnel projects. Our research showed that excavation parameters automatically collected by the TBM, such as excavation speed, cutter head thrust, and cutter head torque, contain noise and require filtering and noise reduction before data mining. Different cutoff frequencies correspond to varying filtering effects, and after considering both smoothness and accuracy, we recommend setting the Butterworth filter's cutoff frequency to 0.1.