TBM Roller Cutter Evaluation Method Based on Analytic Hierarchy Process

Abstract

[Objective] In order to reduce the number of cutter replacements during TBM (hard rock tunnel boring machine) excavation in highly abrasive rock strata and select the most suitable roller cutter for highly abrasive rock strata, a roller cutter evaluation method based on AHP (analytic hierarchy process) is proposed. [Method] An evaluation model for roller cutter wear failure and hazards is established. Seven factors related to wear failure are selected, and an evaluation model and comparative judgment matrix for roller cutter wear failure are developed based on AHP. The proportions of hazard for each failure type are calculated. Taking the interval between Dayuan Station-Taihe Station on Guangzhou-Foshan East Ring Intercity Railway as an example, a quantitative analysis is conducted on four commonly used brands of roller cutters. A risk assessment scoring table is established to analyze the failure impact evaluation values in the use of four roller cutter brands. [Result & Conclusion] The proportion of abnormal cutter wear in highly abrasive rock strata accounts for 23.29%, while normal wear accounts for 76.71%. The failure impact evaluation values for brand C and brand D roller cutters are 7.141 and 4.816 respectively, which are much lower than the failure impact evaluation value of brand A (7.587) and brand B (9.058) roller cutters. The relative wear rate of brand D roller cutters is higher than that of brand C cutters, indicating that brand C cutters are most suitable for highly abrasive rock strata. Brand A roller cutters are suitable for high hardness level rock strata, brand B cutters are not recommended for use, and brand D cutters are suitable for lower hardness level rock strata.

Keywords

• hard rock tunnel
• analytic hierarchy process
• roller cutter evaluation method