Application of the squeezing degree to estimate the specific energy of TBM, case study: Karaj – Tehran water conveyance tunnel of Iran

Tunnel Boring Machine (TBM) is one of the most popular tunneling equipment in the industry. Performance prediction of TBM and the determination of some design parameters have become crucial, as they are critical elements in planning a project of mechanical excavation. The specific energy of TBM (SE), which is defined as the amount of energy required to excavate a unit volume of rock, is one of the most important parameters used for performance prediction degree is an indicator parameter of post failure behavior of rock mass because it is a function of two parameters of these machines. The aim of this work is to estimate the specific energy using the squeezing degree. The squeezing including uniaxial compressive strength of rock mass and in situ stress. So, based on the performed statistical analysis through collected actual data from Karaj-Tehran Water Conveyance Tunnel, a new relationship between the specific energy of TBM (SE) and the squeezing degree is achieved. The results show that there is a direct relation between the specific energy of TBM and squeezing degree and finally three equations is proposed between mentioned parameters for different post failure behavior of rock mass.

کلیدواژه ها:

specific energy for drilling ، post failure behavior ، torque ، thrust ، squeezing ، TBM.