Tall and big space ultra-large air duct assembling device and construction method

The invention provides a tall and big space ultra-large air duct assembling device and a construction method. The assembling device comprises a hoisting bracket and an assembling platform; the hoisting bracket comprises a transverse beam and two bottom beams, the two ends of the transverse beam are connected with the two ends of the two bottom beams through longitudinal beams, stiffening beams arearranged between the two bottom beams, a lifting device is arranged on the transverse beam and used for lifting air ducts, the two ends of the bottom beams are provided with traveling wheels, and profile projections of the longitudinal beams, the bottom beams and the stiffening beams form a triangle; the assembling platform is composed of standard joints of a box frame structure, and the standardjoints are used for allowing the air ducts to be placed; the hoisting bracket cooperates with the lifting device, and the inner space of a venue is utilized to the greatest extent; according to the length of the assembled air