Abstract:
Since early 1980’s, research have been conducted on the prediction of tunnel boring machines (TBM) performance at the Earth Mechanics Institute (EMI) of Colorado School of Mines (CSM). The model for predicting the TBM performance are developed and named as the CSM model. The CSM model approaches are based on the TBM specification (i.e., thrust, torque and power) and rock properties including the uniaxial compressive strength, Brazilian tensile strength, and the brittleness of intact rock together with orientation and frequency of discontinuities in rock mass encountered. The model is semi theoretical but, it has also an empirical database. As the theoretical part of the model is improved in the institute, the utilized empirical database, updated continuously, is obtained from tunneling projects completed at the Earth Mechanics Institute of CSM since last couple of decades. In this study, the CSM model approaches for estimating the TBM performance in massive and fractured hard rock conditions are enlightened and discussed based on updated database. © BeFo and ISRM, 2012.