Analysis of Delamination in Statically Indeterminate Steric Frames Subjected to Fixed Support Rotation

The paper is devoted to the problem of delamination in multilayered steric frames. The attention is focussed on statically indeterminate load-bearing frame structures that are under fixed support rotation. External mechanical loading is not applied on the frames under consideration. Only the stresses and strains induced by the fixed support rotation causes delamination. The layers of the frame are made of structural materials that continuously inhomogeneous in longitudinal direction. Thus, the elastic properties of the layers vary smoothly along the length of the frame portions. Due to steric geometry of the frame, the fixed support rotation generates torsion and bending in the frame portions. Therefore, in this paper we analyze delamination behaviour under combined action of bending and torsion moments. First, the mechanical behaviour of the frame portions is studied by using the equations of equilibrium. Then the strain energy release rate (SERR) is determined by analyzing the frame compliance.