Bottom-hollowed underwater prestressed steel cofferdam device for water-taking working well

The invention discloses a bottom-hollowed underwater prestressed steel cofferdam device for a water-taking working well. The water-taking working well (5) is connected with a water-taking tunnel (1) which is provided with a water feeding pipe (2), and the top of the water feeding pipe (2) is provided with a water inlet (3); a semi-ring-shaped steel cofferdam (4) is arranged in the water-taking working well (5), and the two ends of the semi-ring-shaped steel cofferdam (4) are connected with the inner wall of the water-taking working well (5); and the bottom of the steel cofferdam (4) is fixed to the inner wall of the water-taking working well (5) through a bottom plate (14), and the top of the steel cofferdam (4) is higher than the horizontal plane (11). It is ensured that during detectionand reinforcement operation of the water-taking tunnel (1), no water is leaked at the water inlet (3) to affect the safety of construction personnel, working conditions are provided for detection andreinforcement of the water