Análisis del ensayo DCB de laminados angulares incluyendo tensiones residuales

The aim of the present study is the analytical determination of the energy release rate during the DCB test of angle-ply laminates. With this purpose, an analytic approach based on the complementary energy of a laminated beam including hygrothermal effects is proposed. These effects lead to initial strains that indeed, are impeded by the configuration of the DCB test. The consequent forces and moments are determined by means of Engesser-Castigliano theorem. Once these loads are known, an analytical expression for the energy release rate based on the complementary energy is obtained. Symmetrical and anti-symmetrical angle-ply laminates with 16 plies have been prepared and used for the tests. The configuration of the cracked arms is the same in both laminates, however, the delamination occurs between plies with different orientation. Experimental results of the energy release rate obtained by means of the area method agree with those determined by the proposed approach.