Abstract: To create application conditions for TBM in traffic tunnel construction of a pumped storage power station and achieve the continuous operation of TBM, the crosssection characteristics of traffic tunnels of a pumped storage power station, which is to be built, are analyzed. The crosssection size range is determined and the crosssection design control factors like the steel branch pipe, electromechanical equipment, and construction traffic are optimized. It is found that based on TBM, the electromechanical equipment is the design control factor for tunnel crosssection. Further, two crosssection design schemes, i.e. onetime excavation and invert enlargement construction, are relatively analyzed. The research results show that the two crosssection design schemes can meet the functional requirements of traffic tunnels, while the effective crosssection excavated by invert enlargement construction is larger than that of onetime excavation. The TBM diameter is smaller, and the comprehensive construction difficulty is less than that of onetime excavation, which can meet the overall needs of the pumped storage power station.

Key words:  TBM, traffic tunnel, excavation crosssection, steel branch pipe; transport road, pumped storage power station