The Effect of Delamination Between Layers in U-shaped Members Made of Functionally Graded Multilayered Viscoelastic Materials

Document Type : Research Paper


Department of Technical Mechanics, University of Architecture, Civil Engineering and Geodesy, 1 Chr. Smirnensky blvd., Sofia, 1046, Bulgaria


This theoretical work deals with delamination in U-shaped load-carrying structural members. The latter represent multilayered functionally graded systems of non-linear viscoelastic behaviour. The right-hand vertical part of the structure under consideration is delaminated. The structure is clamped in the lower end of the left-hand vertical part. Besides, the structure is supported by a rotational spring which has non-linear elastic behaviour. The strain energy release rate is derived by using an approach that is based on analysis of equilibrium of the various components of the U-shaped structure. The solution derived is checked-up by applying the method of the integral J. The dependence of the strain energy release rate on different parameters is studied and presented in form of various graphs. Analysis of a U-shaped structural member with two rotational spring supports also is carried-out and the strain energy release rate obtained is compared with that in the U-shaped structure with one rotational spring support.


Main Subjects

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