Modeling and Testing the Fracture Process of Impregnated Carbon-fiber Roving Specimens During Bending: Part I – Fiber Bundle Model

Abstract

A summarizing description of a statistical modeling method partly based on earlier publications is given to predict the total loading and breaking process of fiber bundles generated by tensile tests. This method uses some types of idealized fiber bundles, the so-called fiber bundle cells (basic types: E, EH, ES, and ET) to model the structure of real fibrous structures. Using one of these bundle cells or a composite bundle made of some bundle cells connected in parallel, the expected value and standard deviation of the whole damage process of this bundle can be calculated up to the breakage of the last intact fiber during a mechanical test. As a new application the fracture process of unidirectional composite beam is modeled during the 3P bending test considering the beam is built up of elementary embedded-fiber layers considered as E-type fiber bundle cells in the first step. Formulae for calculating the expected value and standard deviation processes of the bent specimen are elaborated assuming that the fiber breakages determined the failure of layers.