ABSTRACT
In order to push forward retrofit technology for domestic urban bridges, the application and development of retrofit technology for urban bridges have been investigated and researched. At the same time, the key technical points of a bridge retrofit project in Kunming are described in this paper, with emphasis on the construction method of replacing hollow slabs with I-steel composite beams for large-scale viaducts under space-constrained conditions and the construction method of replacing long-span concrete box girders with steel box girders for the upper-span closed-frame passage. The research results can provide a reference for the design and construction of urban bridge retrofit engineering.
