Efficient construction method for pumped storage power station set and temporary supporting structure

The invention discloses an efficient construction method for a pumped storage power station set. The method comprises following steps: casting a large-diameter pit liner, and polishing and machining a seat ring; installing steel supports and hoisting a bottom ring after the large-diameter pit liner is casted; casting the small-diameter pit liner; dismounting the steel supports after the seat ring is polished and machined; and then connecting the bottom ring and the seat ring through bolts and through a welding manner. A temporary supporting structure constructed according to the method mentioned above comprises the large-diameter pit liner (1) and the small-diameter pit liner (2). The large-diameter pit liner (1) is internally provided with the seat ring (3), the multiple steel supports and the bottom ring (4), and the diameter of the bottom ring (4) is larger than the inner diameter of the small-diameter pit liner (2). Each steel support comprises an overhung I-steel (5) and diagonal bracing I-steel (6), and the inclination angle of the diagonal bracing I-steel (6) is 25-35 degrees. The construction method and the temporary supporting structure are advantaged by high security, high stability and high construction efficiency, and a whole construction period can be greatly shortened.