Abstract
Penetration rate is a key parameter for the performance prediction of hard rock tunnel boring machines (TBM), which has a high correlation with rock mass properties. The purpose of this study is to find an appropriate method for estimation of penetrability classification of TBM. To achieve this aim, a similarity measure model and a classification method were proposed based on the similarity measures of intuitionistic fuzzy sets of rock properties. The relationships between actual measured TBM penetration rate and rock properties were discussed by statistical analysis on the published database obtained from Queens’s tunnel project in New York. Then the rock mass parameters were classified into three categories and these normalized categories were transformed into intuitionistic fuzzy sets. According to the Dice similarity measures between the vectors of rock mass properties at each tunnel station, the TBM penetrability conditions in hard rocks can be predicted and described into Good, Medium, and Poor classes. Eventually, in comparison with the measured penetrability results, this suggested method was demonstrated to be effective for penetrability classification with accuracy of 77.5%.
Acknowledgements
The authors would like to thank Prof. Saffet Yagiz, for his valuable data of measured TBM penetration rate and rock properties published in previous literature.
Disclosure statement
No potential conflict of interest was reported by the authors.