Underwater prestressed steel cofferdam device for water intake tunnel water inlet

The utility model discloses an underwater prestressed steel cofferdam device for a water intake tunnel water inlet. A water inlet pipe (2) is arranged on the water taking tunnel (1), a water inlet (3)is formed in the top of the water inlet pipe (2), a steel cofferdam side wall (4) of an annular structure is arranged above the water inlet pipe (2), the bottom of the steel cofferdam side wall (4) is connected with the outer wall of the water inlet pipe (2) through a chassis (5), and the top is higher than a horizontal plane. A plurality of steel bar holes are evenly formed in the steel cofferdam side wall (4) in the circumferential direction, deformed steel bars (8) penetrate through the steel bar holes, the top ends of the deformed steel bars (8) extend out of the top of the steel cofferdam side wall (4), and the bottom ends of the deformed steel bars (8) are located at the bottom of the chassis (5) and provided with prestress locking devices (14) and automatic locking devices (15). And the water inlet (3) is