Abstract: Located in the highaltitude alpine region, SichuanTibet railway is featured by complex geological conditions, numerous superlong tunnels, large burial depth, poor setting conditions for auxiliary tunnels and high environmental protection requirements. Smooth tunnel construction is one of the key factors for successful construction of SichuanTibet railway. According to the preliminary investigation and research, construction of such a great number of superlong tunnels by the drilling and blasting method can be very challenging. It is believed that TBM tunneling is a better choice for construction of long tunnels for SichuanTibet railway in the highaltitude alpine region. However, TBMs have seldom been applied in similar conditions. By considering the geological conditions, environmental characteristics and general requirements of SichuanTibet railway Tunnels, and the advantages and disadvantages of various types of TBMs, systematic analysis and indepth comparison are conducted for application of TBMs in construction of SichuanTibet railway tunnels. The basic principles of TBM selection and TBM adaptability are discussed. Some suggestions and thoughts are put forward on targeted TBM design, construction measures and project progress, aiming at the unfavorable geology along SichuanTibet railway.

Key words: SichuanTibet railway tunnels, TBM, adaptability, type selection, measures for unfavorable geology