Underground passage supporting structure for underneath passing existing large-section shallow-buried pipe gallery

The utility model provides an underground passage supporting structure penetrating an existing large-section shallow-buried pipe gallery downwards, cast-in-situ bored piles are arranged at the four corners of the intersection of the pipe gallery and the underground passage structure in a driving mode, and the tops of the cast-in-situ bored piles on the single side of the underground passage structure are connected through a top beam. The tops of the cast-in-situ bored piles on the two sides of the underground passage structure are connected through transverse concrete supports. A plurality of I-shaped steels are inserted into a soil body below the bottom of the pipe gallery and are attached to the bottom of the pipe gallery; a concrete supporting beam is arranged below the I-shaped steel and attached to the I-shaped steel, the two ends of the concrete supporting beam are connected with the cast-in-situ bored piles on the two sides of the underground passage structure, the underground passage structure is loca