Geometrically Nonlinear Analysis of Long Span Composite Girder Cable-Stayed Bridge with Three Towers under Live Load

Abstract

A comparison on geometrically nonlinear analysis of composite girder cable-stayed bridge is presented. The spatial nonlinear analysis model named double-girder is established, the geometrically nonlinear behavior of whole bridge is analyzed under dead load plus live load in normal service stage, the nonlinear analysis involves cable sag, large displacement and beam-column, the three nonlinear factors effect on internal force and deformation of side tower, main girder are investigated. The results show that the effect of geometric nonlinearity is small on bending moment and deformation of side tower, and also small on vertical deflection of main girders, but nonlinear effect is large on bending moment of main girders. Results obtained in this research and conclusions made provide valuable insight and guidelines for the design of composite girder cable-stayed bridge with three towers.