Effects of shear connection limited ductility in steel-concrete composite beams prestressed by unbonded tendons

In this paper a finite element approach is proposed to study the non-linear behaviour of externally prestressed composite beams with flexible shear connection. The solution of the problem is achieved by the displacement control method which makes it possible to capture the complex non-linear behaviour of the girder even if fragile failure occurs. Some applications on a simply supported beam and on a two-span continuous beam are reported and discussed showing the importance of the limited ductility of the shear connection in defining the collapse mechanism.