ULTIMATE BENDING BEHAVIOR OF EXTERNAL TENDON-REINFORCED PRESTRESSED-CONCRETE GIRDERS MADE CONTINUOUS BY NO-JOINT METHOD

A study was made, by nonlinear analysis and static load experiments, into the ultimate bending behavior and failure mechanism of continuous prestressed-concrete girders in which simple girders of an existing highway bridge were joined by a no-joint construction method and reinforced with external tendons. It was found that because of the improved flexural capacity due to the increased external tendon stress accompanying the deformation of the structural members, the moment redistribution that occurs with the deformation of the plastic hinges of the intermediate supports predominates, the load-carrying capacity of the girders is improved, and safety against flexure is satisfied. Also, an analysis method is proposed that makes use of secant stiffness to directly reproduce the structural system in the plastic region.