TBM performance and disc cutter wear prediction based on ten years experience of TBM tunnelling in Iran

Accurate estimation of rate of penetration (ROP), daily rate of advance (AR), and cutter cost/life is necessary for the justification and successful use of a TBM on any tunneling project. Various models have been introduced over the years to provide such estimates. In many cases, these models have been successful with pin point accuracy, and in other instances off by a wide margin. Improving the accuracy of performance prediction models for hard rock TBMs has been the subject of many studies, some yielding project-based models and some more universal models that can be used elsewhere. This paper will discuss the latest version of a new empirical model for estimating penetration rate and disc cutter life for hard rock TBM tunneling based on recent tunneling projects, constructed during the period 2002-2009. The new model was then applied to predict TBM performance and disc cutter wear in different mechanized tunneling projects under construction since 2009. Accuracy and validity of the model for prediction of ROP were checked by comparing predicted and measured values of TBM performance in 24 km of newly bored tunnel. The results indicate that despite some minor deviations in estimates in some tunnel sections, reasonable agreement can be observed between predicted and actual ROP of TBMs.