One-time in-place splicing control method for large-span arch bridge pre-splicing manufacturing

The invention discloses a one-time in-place splicing control method for large-span arch bridge pre-splicing manufacturing, and relates to the technical field of bridge design. The method specifically comprises the steps that S1, three-dimensional scanning is conducted on arch rib sections to be assembled, and an actual arch rib point cloud model is obtained; s2, performing optimal matching on the actual arch rib point cloud model and the theoretical arch rib point cloud model to obtain an optimal pre-splicing posture of the arch rib; s3, extracting the center line of the optimal pre-splicing posture of the arch rib; s4, calculating the three-dimensional coordinates of the jig frame under the optimal pre-splicing posture of the arch rib; s5, pretreatment is conducted before the to-be-assembled arch rib is placed; and S6, the arch rib to be assembled is placed on the jig frame with the determined three-dimensional coordinates, and arch rib entity pre-assembling posture adjustment work is completed. According to