INFLUENCE OF FINITE WIDTH AND ELLIPTICAL ASPECT ON NOTCHED LAMINATE STRENGTH PREDICTIONS

The notched strength of composite laminates is commonly predicted by first determining the. stress distribution within a laminate and subsequently applying a stress fracture criterion to it.Difficulties are encountered in predieting the notched strength because there are no closed-form expression of the stress distribution near the notch in orthotropic materials for finite width plates,ln this paper a finite clement stress analysis is presented for isotropic and orthotropic plates containing as elliptical opening, Formulae for estimating the stress concentration factor K_T and stress distribution σ_y(x,0) near the opening are proposed,in which the influences of finite width and elliptical aspect on K_T and σ_y(x,0) have been taken into account reasonably. Both finite width and elliptical aspect exert an influence on K_T and σ_y(x,0) although the former exert a greater influence than the latter.It also can be seen that the notched strength predicated by the traditional methodology is unreliable.