Slip locking in finite elements for composite beams with deformable shear connection.

In this paper, the authors discuss problems that may occur in the finite element analysis of composite beams with deformable shear connection, where slip arises between beam components while contact is preserved. E2ects of locking problems, comparable to the membrane and shear locking that may develop in finite elements for common beams, are illustrated. These locking problems mostly a2ect the description of the curvature and interface slip. A strategy to avoid locking by means of a calibrated choice of the displacement shape functions is then proposed and a comparison between di2erent displacement-based elements, in terms of local error, global error and convergence rate, is presented. The authors also illustrate the effects of slip locking on mixed !nite elements and comparisons between displacement-based and mixed elements are shown.