STP772: Statistical Fracture Initiation in Randomly Oriented Chopped-Mat Fiber Composites Subjected to Biaxial Thermomechanical Loading

    Wang, SS
    Associate Professor and Graduate Research Assistant, University of Illinois, Urbana, Ill.

    Yu, TP
    Associate Professor and Graduate Research Assistant, University of Illinois, Urbana, Ill.

    Pages: 16    Published: Jan 1982


    Abstract

    Owing to the inherently heterogeneous microstructure of constituent elements and the random orientation of fiber mats, initiation of local fracture in chopped-mat fiber composite materials is statistical in nature. An analytical approach is presented in this paper for studying the fracture initiation. The study is formulated on the basis of the statistical failure theory and fundamental concept of mechanics of fracture for brittle fiber composites. The heterogeneity of chopped fiber mats with random orientations and the effect of biaxial thermomechanical stress are incorporated into the Weibull strength theory. A computer simulation procedure with the aid of a numerical stress analysis is introduced. Estimation of the location of fracture initiation in a statistical sense is conducted for the disk-type chopped-mat fiber composite. Selected results are presented to illustrate the fundamental nature of the statistical fracture initiation behavior in this class of composite material.

    Keywords:

    chopped fiber mat, fiber reinforced composite, fracture initiation, statistical strength theory, thermomechanical stresses, failure probability, Weibull's weakest-link model


    Paper ID: STP29384S

    Committee/Subcommittee: E08.07

    DOI: 10.1520/STP29384S


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