| Abstract:Rong River Large-Span Bridge, locating on the passenger-dedicated railway from Xiamen to Shenzhen, is a flexible arch bridge with steel truss girders and orthotropic steel deck. The main span is (110+2×220+110) meters long, the longest span among similar-type bridges in the world.Combined with engineering construction practice and the original research projects of Ministry of Railways, the key construction technology, such as the flexible arch construction scheme, main pier foundation construction and the cushion scheme of the steel bridge deck is studied in this paper. The main works are introduced as follows:(1) The history, current research situation and development trend of the structure and construction technology of similar-type bridges both at home and abroad are investigated and summarized.(2) By conferring to the construction scheme of similar domestic bridges, combining with site hydrology, geological conditions and the time limit for the project, and considering the navigation requirements, transport conditions of members and nodes and other factors, four construction schemes of the main bridge are formulated. After comparing the technology, time limit,resource input, the convenience and safety of navigation, etc, the scheme of "bracket beside the pier+symmetric erection of double cantilevers+separate closure of the main span" is proposed.(3)Based on the overall construction scheme, the main construction procedure from preparation to completion is raised and the study of key technology on the factory of the prefab girder, trestle bridge, temporary buttress and support is carried out.(4)Mechanical analysis and inspection during the most unfavorable conditions in the process of cantilever construction of the main span steel truss beam to verify the safety of the construction procedure.(5) The research on craft and control technology is conducted in this paper, including in-water measurement, the foundation of deep-water bored cast-in-place pile, double wall steel cofferdam, and the bearing platform above the water.(6)By the analysis and comparison of the orthotropic steel bridge deck cushion, high-adhesive light protective cushion and MMA high-performance waterproof coating based new deck cushion structure is recommended. The construction technology and quality control measures of MMA are put forward.Practice demonstrates that the construction method, craft and control technology of this bridge is reasonable and reliable, and it may contribute to the design and construction of other similar bridge structure. |
