Supporting trolley for variable-section excavation of cavern

The utility model relates to the field of engineering mechanical equipment, and discloses a support trolley for cavern variable section excavation, which comprises a trolley main body and an I-shaped steel support frame, a positioning column is fixedly arranged on a frame of the trolley main body, a top construction platform is arranged at the top of the I-shaped steel support frame, and a vertical column of the I-shaped steel support frame is sleeved on the positioning column. A lifting oil cylinder is further installed on the trolley frame of the trolley body, the I-shaped steel supporting frame ascends and descends along the positioning columns through the lifting oil cylinder, a telescopic piece is arranged on the side face of the I-shaped steel supporting frame, a side face construction platform is fixedly arranged on the telescopic piece, a telescopic oil cylinder is fixedly arranged on the side face of the I-shaped steel supporting frame, and the telescopic oil cylinder is used for pushing and pulling