Identification of cutter flat wear for rock TBMs using vibration signal of shield

Abstract

Identification of cutter wear status is one of the critical issues for the successful operation of tunnel boring machines (TBM). This study proposed a novel model for predicting the locations of cutters experiencing flat wear, leveraging measured vibration signals from the TBM shield. Field tests were conducted to collect vibration acceleration data using accelerometers. This paper outlines the equipment and setup for monitoring vibration acceleration and develops procedures for signal processing. Analysis of vibration acceleration patterns reveals distinct characteristics corresponding to varying numbers and locations of cutters with flat wear. A linear relationship can be identified between the frequency of different vibration acceleration peak intervals and the extent of flat wear on the cutters (number and location of wear cutters). The proposed model is then applied to a TBM tunnelling section in Guangzhou, China, and validated using on-site wear data. This method offers real-time insight into the potential need for cutter replacement during tunnelling operations in challenging hard rock conditions.