Outer Formwork for Open Cut Structure of Hydraulic Tunnels and Construction Method

The present invention discloses an outer formwork for open cut structure of hydraulic tunnels and a construction method, comprising multiple sets of outer formworks arranged longitudinally along the central axis, wherein the outer formworks comprise an outer formwork A, an outer formwork B and an outer formwork C, which are arranged symmetrically; the outer formwork A, the outer formwork B and the outer formwork C are connected with the outer formworks arranged longitudinally along the central axis; a group of back frame is in corresponding connection with the upper part of each set of outer formwork, and a pair of vertical supports is symmetrically connected at two sides of each set of the outer formwork. The present invention enlarges the working surface from the undercut to the open cut and provides space conditions for the development of large equipment.