Construction Scheme Research of Long-span Cable-stayed Bridge with Three Pylons Based on Structure Stability

摘要

This paper took the Wuhan Erqi Yangtze River Bridge as an example, using MIDAS software to simulate the working procedure of cantilever construction, and established the finite element model of composite girder cable-stayed bridge with three pylons during construction stage. Based on the first kind stability theory, this paper researched the influence of the different construction scheme, the setting of temporary pier, temperature load, and unbalanced construction load on the structure stability of composite girder cable-stayed bridge with three pylons so as to obtain the linear elastic stability safety coefficients of structure during construction stage, and then provided the theoretical explanation to the reasonable construction scheme and safety construction. The results showed that for the Wuhan Erqi Yangtze River Bridge, its linear elastic stability safety coefficients of structure during construction stage have met the code requirement. Besides, the buckling mode changed from the longitudinal buckling of pylon to combined instability of pylon and girder. Furthermore, the setting of temporary pier was reasonable, which effectively improved the linear elastic stability safety coefficients. Finally, temperature load and unbalanced load in construction reduced the linear elastic stability safety coefficients.