Accession Number : AD0712122

Title :   THE DYNAMIC ORTHOTROPIC DUGDALE MODEL,

Corporate Author : VIRGINIA POLYTECHNIC INST BLACKSBURG DEPT OF ENGINEERING MECHANICS

Personal Author(s) : Gonzalez,H. , Jr. ; Brinson,H. F.

Report Date : AUG 1970

Pagination or Media Count : 42

Abstract : The problem of ductile fracture in anisotropic solids is an important engineering problem. In this report the Dugdale model is assumed, that is, the yielded zone is replaced by a constant yield stress. A solution is presented for an orthotropic dynamic solid. The solution was obtained by the complex variable approach. Stress functions which must satisfy a generalized bi-harmonic equation are represented in terms of two analytic functions of two different complex variables. In this way boundary value problems can be reduced to problems of complex function theory. The yield stress is assumed to follow a Von Mises' yield criterion which was adapted to the orthotropic dynamic case. It was found that the plastic zone is given by the same relation as in the isotropic-static case. Any orthotropic dynamic parameter may be obtained from the corresponding isotropic dynamic parameter by simply multiplying the orthotropic parameter by a coefficient. A limit on yielding along the line of the crack and therefore a limit on the anisotropy and velocity are derived. (Author)

Descriptors :   (*CRACK PROPAGATION, MATHEMATICAL MODELS), STRESSES, LOADS(FORCES), FRACTURE(MECHANICS), EQUATIONS OF MOTION, BOUNDARY VALUE PROBLEMS, ELASTIC PROPERTIES

Subject Categories : Mechanics

Distribution Statement : APPROVED FOR PUBLIC RELEASE