Abstract:Being aimed at the third bridge over Fu river in the city of Mianyang, Sichuan, a tied arch bridge with concrete-filled steel tubes andwith a main span of 202 m, a 3-dimensional compound structural calculation model constructed by flat shells, beams, trusses and rope elements is used to analyze the structural behaviorof the bridge. In the analysis, the structural nonlinearity and ultimate bearing capacityof members are considered, and the deformations during construction and the superposition effectof stresses are also taken into account. The emphasis of the study is focused on the deformations, internal forces and stability of the bridge during construction.