TBM Performance Prediction in Iran

In order to prevent shortage of drinking and industrial water for the next two decades in the city of Tehran, according to growth requirements, many projects have been designed and implemented. The Karaj-Tehran water tunnel is one of these. This tunnel, approximately 16km long, is being excavated by full-face TBM to carry water from Amir Kabir dam to Tehran refinery no.6. Because of their rapid excavation speed, TBMs have a special place in more than 6km of tunnelling in Iran. Predicting the machine excavation work, especially in longterm projects, has become very important, considering the growth in the use of these methods from early 1990s. Many prediction methods are available, such as those of the Colorado School of Mines, Norwegian rock mass quality index (RMi of RockMass) and the TBM Tunnelling Quality Index (QTBM). In this paper, to analyse the Karaj-Tehran project the Norwegian rock mechanics method (RMi) and the TBM Tunnelling Quality Index methods were used