Nowadays, mechanized tunneling systems are frequently used in tunneling projects. For this aim, three basic systems including full face tunnel boring machines (TBMs), mobile miners, and roadheaders or boomtype machines are applied. The high capability of full-face mechanized tunnel boring machines in adverse geological conditions, including rocky and alluvial structures, has led to the widespread use of these machines in construction of urban mechanized tunnels, water conveyance tunnel, and road tunnels. Despite various applications of these machines, TBMs have been used less frequently in mining projects. However, some good examples of TBM application and other mechanized tunneling techniques for mine development are reported. TBM excavation is a continuous process, with cutting, mucking, and support installation proceeding concurrently. This presentation aims to emphasize on historical development and innovations in mechanized tunneling, various types of full face tunnel boring machines (e.g., shielded or open-type TBMs for tunneling in hard rock; and earth pressure balance, slurry shield and open face type for tunneling in soft ground), the field of application for different types of TBMs, the process of boring operation and evaluating the performance of these machines. Furthermore, some experience of TBM applications in Iran will be mentioned.
