METHOD OF STATE DECOMPOSITION AND SLICE COMPOSITION ONELLIPTICAL DELAMINATION IN COMPOSITE LAMINATE

The transverse loading state of a laminate with elliptical delaminations is decomposed by means of the principle of superposition, so the problem of delamination can be reduced to the analysis of the additional displacements and stresses caused by the additional shear loading acting on the delamination surfaces, and thus a simple mechanics model of the delamination area is established. The laminate sections parallel to the coordinate planes can be regarded as laminated beams with delaminations, the displacements of which can be expressed by the analytical solutions of the additional displacements in the above beams. In this way, the additional displacement fields satisfying the displacement boundary condition of the delamination area can be established. Finally, a closed form solution of additional displacements is obtained by the principle of minimum potential energy. The above results are compared with the convergent solutions obtained by the method of trigonometric series. It shows that the deflections acquired from two different ways agree with each other very well and are greater than the in plane displacements by 1~2 order of magnitude.