Engineering Fracture Mechanics (in press)
Z.
Dong
G.H.
Paulino
Department of Civil and Environmental Engineering, University of Illinois at Urbana-Champaign, Newmark Laboratory, 205 North Mathews Avenue, IL 61801, U.S.A.
Abstract
A nonhomogeneous, functionally graded, elastic strip containing an interior crack arbitrarily located with respect to the material property gradient direction is investigated using a singular integral equation formulation. The crack is parallel to the upper and lower edges and subjected to self-equilibrating crack surface loadings. The problem is solved under plane strain and generalized plane stress considering four basic types of boundary conditions (BCs): semi-infinite, fixed, mixed and traction-free. The BCs for the upper and lower edges can be chosen separately from the four basic types, leading to a total of sixteen sets of distinct BCs. The results obtained include crack opening displacements, crack sliding displacements, and mixed-mode (I & II) stress intensity factors. The influence of several factors on these results is investigated such as BCs, crack length, thickness of the strip, relative position of the crack, Poisson's ratio, material gradient, and loading distribution.
Key words: Functionally graded
material, stess intensity factor, integral equation method, mixed mode crack
problem