چكيده به لاتين
In the present work, comparing the non-localized and classical failure, when examining the stress of the crack tip in the first mode of failure, is considered for an orthotropic composite material made of glass fibers and epoxy resin. One of the reasons for trying to compare these two theories with each other is the existence of infinite stress at the tip of the crack based on the failure of the classical theory and also the study of the effect of existence and absence of this infinite stress on the amount of the critical stress intensity factorof the piece.
In this thesis, firstly, the classical stress fields as well as the factor of the critical stress intensity of the first mode of failure were calculated through modeling in Abakus software. Then, due to the fact that in the nonlinear theory of strain and displacement fields with the theory of non-localized stress fields, are calculated with the Eringen equations. Then the amount of factor of the critical stress intensity of the first mode of the (K_IC) of the composite plate has been calculated and compared with the critical stress intensity factor of classical theory.
Finally, we conclude that, according to the calculations, the tip stress of the crack is non-infinite and limited amount, and the critical stress intensity factor, regardless of the non-nominal and classical failure theory, is constant amount.
