The Pingnan Third Bridge, with a main span of 575 m, is currently the world's largest arch bridge. It features large diameter tubes, a vast span, and is situated in a flat plain. The construction of the north bank involves underground continuous wall construction. Several innovations have been applied in the construction of this bridge: (1) High-precision manufacturing technology for the arch ribs. High-precision manufacturing of the arch ribs has been achieved through the application of techniques such as BIM and Tekla structures construction drawing detailing, flange plate precision machining, and the “3 + 1” horizontal matching manufacturing technology. (2) Optimization technology for one tensioning and dismantling of the cable in the cable-stayed buckle system. Based on the principles of the influence matrix and the optimization calculation theory of “optimal process, controllable result”, an optimal calculation method for the one tensioning of cable-stayed anchors during arch bridge construction has been established. In response to the time-consuming and high-risk traditional method of loosening the cables step by step, a rapid cable-loosening method has been proposed, which involves alternately loosening the cables from the arch foot to l/4 of the arch and then to the arch crown based on an analysis of the impact of loosening individual anchor cables at different positions on the structural deformation. (3) Vacuum-assisted grouting and four-stage continuous pumping technology. To address the issue of gaps forming at the top of the tubes and inner flanges in traditional grouting and pressure injection processes, a vacuum-assisted grouting method and equipment for concrete inside the tubes have been developed. Relevant experimental research has been conducted, resolving the long-standing issue of air voids in the concrete inside the tubes.