A DETAILED ANALYSIS OF CRACKS BRIDGED BY FIBERS .1. LIMITING CASES OFSHORT AND LONG CRACKS

TWO AXISYMMETRIC bridged crack problems that correspond to the limitin g cases of short and long cracks are studied. The objective is to unde rstand such details of crack bridging as the tensile stress distributi on in bridging fibers, the effect of bridging on crack propagation and the load transfer from bridging fibers to the matrix. The solution me thod, which accounts for interfacial slip explicitly, involves the use of continuous distributions of dislocation loops to represent the ope ning of the crack and the slip at the fiber-matrix interfaces. This yi elds a set of coupled singular integral equations, which are solved nu merically. In Part II, cracks of intermediate size will be studied. Th e results will be used to determine the effect of initial flaw size on the proportional limit and to assess the range of validity of a commo nly used model of crack bridging in which bridging fibers are represen ted by distributed springs.