Underwater directional cutting device for concrete and cutting method thereof

The invention discloses an underwater directional cutting device for concrete and a cutting method of the underwater directional cutting device. The cutting device comprises a dismounting frame and a lifting dismounting module. The lifting dismantling module comprises a bottom plate, a rotary table, a supporting plate, a vertical plate, a circular ring and a connecting frame. According to the device, manual work can be replaced to dismantle the concrete structure of the cofferdam, the overall dismantling process is that breaking is conducted firstly and then cutting is conducted, the convenience of actual dismantling is improved, manual work can be replaced to complete underwater dismantling work, the labor intensity of constructors is reduced, potential safety hazards existing in dismantling construction are reduced, high practicability is achieved, and the device is suitable for popularization and application. The overall safety is high; and multiple construction procedures can be completed at the same time