China Railway Engineering Equipment Group Co., Ltd. (CREG) has reported its 3.35m diameter compact TBM ‘Wendeng’, had successfully bored the first 270m of tunnel on the drainage gallery structures of the Wendeng pumped storage power station in China’s Shandong Province.
Wendeng passed the Factory Acceptance Test at CREG’s Luoyang base on September 10, 2019 and launched on October 13. Compared to an ordinary TBM, Wendeng is smaller with a total length of only 37m.
The five diversion structures of the Wendeng pumped storage power station are located within a complex formation some 300m deep within the Kunyu Mountain and pass through 7 curves and 8 faults over 2300m in length. The water diversions have a maximum gradient of 55°and an average length of 1140m. The layout of the five bores is like a labyrinth with a minimum spacing of only 3m.
With a total weight of about 250t, the TBM has a length some 80% shorter than conventional TBMs and a turning radius of just 30m, allowing it to turn at an angle of around 60°to complete the assembly, launch, tunnelling, turning, reception, disassembly and other operations within the narrow cavern space.
The Wendeng pumped storage power station, with a planned installed capacity of 1800MW, is the largest storage power station in the Shandong province and scheduled to be completed by June 2022. This project introduces the TBM method of construction of a pumped storage power station for the first time in China.