A comparative study for beams on elastic foundation models to analysis of mode-I delamination in DCB specimens

作者：Shokrieh Mahmood Mehrdad^*; Heidari Rarani Mohammad

来源：Structural Engineering and Mechanics, 2011, 37(2): 149-162.

• delamination
• compliance
• strain energy release rate
• beam theory
• elastic foundation

The aim of this research is a comprehensive review and evaluation of beam theories resting on elastic foundations that used to model mode-I delamination in multidirectional laminated composite by DCB specimen. A compliance based approach is used to calculate critical strain energy release rate (SERR). Two well-known beam theories, i.e. Euler-Bernoulli (EB) and Timoshenko beams (TB), on Winkler and Pasternak elastic foundations (WEF and PEF) are considered. In each case, a closed-form solution is presented for compliance versus crack length, effective material properties and geometrical dimensions. Effective flexural modulus (E(fx)) and out-of-plane extensional stiffness (E(z)) are used in all models instead of transversely isotropic assumption in composite laminates. Eventually, the analytical solutions are compared with experimental results available in the literature for unidirectional ([0 degrees](6)) and antisymmetric angle-ply ([+/- 30 degrees](5), and [+/- 45 degrees](5)) lay-ups. TB on WEF is a simple model that predicts more accurate results for compliance and SERR in unidirectional laminates in comparison to other models. TB on PEF, in accordance with Williams (1989) assumptions, is too stiff for unidirectional DCB specimens, whereas in angle-ply DCB specimens it gives more reliable results. That it shows the effects of transverse shear deformation and root rotation on SERR value in composite DCB specimens.

• 出版日期2011-1-25