Three-dimensional modeling method for half-bearing frame girder

The invention discloses a three-dimensional modeling method of a half-bearing frame girder, which comprises the following steps that: girder parts on two sides are only independently designed in size and shape, and when the girder parts on the two sides are arranged in a frame assembly, the girder part models on the two sides are not provided with hole sites; establishing a skeleton model file under the frame assembly model; a corresponding reference plane is designed in the middle of the skeleton model, and design hole sites corresponding to hole sites in the frame girder model are arranged on the reference plane; activating the girder part in the frame assembly model, removing materials by referring to the designed hole displacement in the skeleton model, and generating a hole site on the girder part; and respectively activating other part models, and generating all hole sites on the girder. Hole sites do not need to be drawn independently on each part, all the hole sites only need to be designed once on th