Abstract: In order to quantitatively evaluate the adaptability of open-type TBM under complex geological conditions, and to solve the problems of fixed index weights and insufficient representativeness of the research subject in the traditional evaluation methods, the authors propose a fuzzy comprehensive evaluation method based on dynamic weights with the Northern Xinjiang Water Supply Project Phase Ⅱ as the background. First, the key factors affecting the geological adaptability of TBM are systematically analyzed, and seven sensitivity indexes, including surrounding rock class, rockburst, large deformation, fault fracture zone, water-rich alteration zone, karst area, and water-rich fissure zone, are selected to establish the evaluation index system, and the membership function of each evaluation index is determined. Second, the variable weight calculation method is innovatively introduced. Based on the ratio of the tunneling time in different geology to the total tunneling time of each TBM, the variable weight of different geology is calculated, and then the adaptive fuzzy comprehensive evaluation method is established. The adaptability score is obtained through fuzzy operation and divided into five levels. The adaptability of 18 open-type TBMs in the main tunnel is evaluated, and the results show that the adaptability is poor for 1 TBM, limited for 2 TBM, moderate for 3 TBM, good for 7 TBMs, and excellent for 3 TBMs, and the evaluation results are highly consistent with the actual situation. The analysis shows that efficient tunneling can be achieved in the surrounding rock with a score of 85 or more for good or excellent adaptability, which can support efficient tunneling with an average utilization rate of more than 35%, an average availability rate of more than 90%, and an average monthly advance of more than 400 m.

Key words: open-type TBM, geological adaptability, fuzzy comprehensive evaluation method, variable weight analysis, membership function, unfavorable geology