A NEW APPROACH TO THE ANALYSIS OF UNIDIRECTIONAL TITANIUM MATRIX COMPOSITES WITH BRIDGE AND UNBRIDGED CRACKS

An alternative method to the continuum approach for calculating the fi ber stresses and crack opening displacements for a longitudinal lamina e containing a crack that may be bridged by unbroken fibers is develop ed. The composite is modeled as discrete cells containing a fiber and the surrounding matrix material. Shear lag theory including the stiffn ess of the matrix material is used to formulate the stress-strain-disp lacement relations. The method allows for the implementation of differ ent crack bridging laws for each composite cell including the presence of broken fibers among intact, bridging fibers. Results are compared with results from the literature and finite element analysis. The capa bility of this method to model broken fibers among bridging fibers in the crack wake is demonstrated through an example. (C) 1997 Published by Elsevier Science Ltd. All rights reserved.