Ultimate behavior of cable stayed bridges under construction: Experimental and analytical study

While the girders of cable stayed bridges are designed to be slender, they are subjected to large compressive forces, causing a stability problem. If cable stayed bridges are constructed using the balanced cantilever method, the stability problem of the girder is more significant during the construction stage than at the initial state. In this study, to investigate the ultimate behavior of cable stayed bridges, experimental and analytical studies were conducted for three models: Harp type 1, Harp type 2, and Semi-Harp type. At the limit state, several inner cables lose the initial tension, several plastic hinges occurred and the girders buckle along the entire span. Experimental results show that the geometrical and material nonlinearity of cable stayed bridges are the governing factors along with the successive loss of cable tension. Numerical analysis was also conducted for each experimental model, the results of which showed good agreement with the experimental results.