Weakening of elastic solids by arrays of cracks

Thesis/Dissertation · Tue Jan 01 04:00:00 EST 1974

OSTI ID:5042154

Delameter, W R

The stress intensity factors and the effective elastic constants of an infinite body with a doubly periodic array of parallel slit-like cracks are determined. The material is isotropic (although the response of the body with cracks is anisotropic) and linearly elastic, and the cracks are arranged in one of 2 patterns: (1) a rectangular array or (2) a diamond-shaped array. The problems are formulated by representing each crack by suitable continuous distributions of straight dislocations. Singular integral equations for the dislocation distribution functions are obtained by requiring that the crack faces be traction-free, and an approximate numerical method for the solution of these integral equations, which begins with the expansion of the nonsingular part of the kernel in a series of Chebyshev polynomials, is presented. It is shown that a solid containing a doubly periodic array of cracks, subjected to inplane shear stress (Mode 2), is generally weaker (i.e., will fracture at a lower level of applied load) than a similar body which contains a single crack of the same length. That is, the cracks interact such that the stress intensity factor increases. It is also shown that the effective shear modulus of the body is reduced considerably by the presence of the cracks.

• OSTI ID: 5042154
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360103* -- Metals & Alloys-- Mechanical Properties
360603 -- Materials-- Properties
CRACK PROPAGATION
ELASTICITY
FRACTURE MECHANICS
MATHEMATICAL MODELS
MECHANICAL PROPERTIES
MECHANICS
SOLIDS
STRESS INTENSITY FACTORS
TENSILE PROPERTIES