Box type main beam structure capable of reducing uplift pressure of plane emergency gate of water stopping of downstream positions

The invention discloses a box type main beam structure capable of reducing uplift pressure of a plane emergency gate of water stopping of downstream positions. The box type main beam structure comprises a box type main beam body (1) of the plane emergency gate; the box type main beam body is provided with through holes penetrating through an upper web (2) and a lower web (3), and communicating pipes (4) are arranged in the through holes; a communicating hole (6) is formed in the back wing edge of the box type main beam (1). The communicating pipes are equidistantly arranged between the upper web and the lower web of the box type main beam of the gate, the communicating hole is formed in the back wing edge of the box type main beam of the gate, and water between the upper web and the lowerweb is communicated through the communicating pipes; the water can flow into a cavity body between the upper web and the lower web through the communicating hole, the water pressure difference of theupper web and the lower we