Abstract:

 Herein, the current development status of mechanized tunnel excavation is summarized based on analyzing typical tunnel projects in a pumped storage power plant(PSPP) constructed by tunneling machinery. It is found that: (1) The modern drill and blast machinery, such as drill jumbos, are commonly used. (2) Roadheader is in trail application. (3) The fullsection hardrock tunnel boring machines(TBMs) have been successfully verified for their feasibility and are promoted for use in small diameter tunnels. (4) Large diameter TBMs have completed tunnel excavation tests. (5) aise boring machines are widely used in inclined and vertical shafts. (6) The feasibility of shaft boring machines has been validated. (7) Inclined shaft TBMs are on their way for use in excavation. The current problems in the mechanization of PSPP tunnel excavation are revealed; the following causes are analyzed: high construction cost and difficulty in popularizing, weak universality and the lack of application cases for some new mechanical equipment, hardtoreplace traditional systems and conservative concepts, insufficient equipment operators, and low overall quality of operators. Based on the current technical level and market status, it is proposed that tunneling machinery used in PSPPs will certainly be developed toward electrification, automation, and intelligence, and the use of applied TBMs and shaft boring machines will be further promoted. Moreover, more tunneling machinery will be studied and developed, with the aim to promote the advancement of tunneling technology and mechanization level of PSPPs in China.

Key words: pumped storage power plant, tunnel, mechanization, raise boring machine, hardrock tunnel boring machine, shaft boring machine, noncircular/partial face tunnel boring machine