Analytical algorithm for the full-bridge response of hybrid cable-stayed suspension bridges under a horizontal transverse live load

Abstract

Hybrid cable-stayed suspension bridges (HCSSB) enjoy broad application prospects due to their excellent stability and economic benefits. The full-bridge response of this novel bridge type under a live load is a shared concern during the design and use stages. This paper proposes an analytical algorithm for solving the full-bridge response under the horizontal transverse live load. First, the entire bridge is subdivided into several components, and the mechanical model and response calculation theories are built for each component. However, some critical parameters for solving these models are still unknown, and these unknown parameters are treated as basic unknown quantities. The system of governing equations is built, considering the conservation of the unstrained lengths of cables, closure of span lengths, and elevation difference across the spans. Finally, the system of governing equations is solved to obtain the full-bridge response. The results include the deformation and internal force of the main cables, main beam, towers, stay cables, and hangers. Finally, the feasibility and effectiveness of the analytical method are verified in an HCSSB with a main span of 1400 m by comparing the full-bridge response results against those from the finite element model.