Abstract:To solve the difficulties of local boundary condition simulation and analytical precision guarantee for analyzing the springing joint of CFST tied-arch bridge by traditional elaborate finite element model, a new modeling idea of introducing global scale model to local accurate finite element model of springing joint with reasonable connections was proposed based on the multi-scale modeling theory. The multi-scale modeling method was also developed to investigate the behaviors of springing joint for CFST tied-arch bridge. The mechanical behavior and the safety of springing region of a CFST tied-arch bridge with computed span of 96 m and rise-span ratio of 1/5 were investigated. The results show that the concurrent multi-scale modeling method can not only model the local boundary conditions of CFST tied-arch bridge, but also can predict the mechanical behavior of springing joint with significantly reduced computation cost. The stress in springing joint is reasonable, while the stress concentration in prestressed anchorage zone and near supports is obvious.