The Appliaction of the Finite Element Method to Fracture Mechanics Problems

A new finite element which adequately represents the character of<br/>the strains near the crack-tip is presented. The element is based on displacement functions, derived from, assumed simple strain functions, by integrating the strain - displacement equations. The resulting displacement functions contain terms associated with the rigid body modes.<br/><br/>The element is 'trapezoidal' in shape with two straight and two circular boundaries. A 'triangular' crack-tip element based on assumed simple displacement functions is also presented. This element has two of its boundaries straight, meeting at the tip of the crack, and the other circular.<br/><br/>When employed in the singular region of the crack-tip, using as few as 312 degrees of freedom, these elements give results for displacements and stresses whose accuracies are within l«57o and ~y/o , respectively, of 'exact' solutions. The elements are combined with Constant Strain Triangular elements to analyse practical geometries used in fracture toughness testing*<br/>Relatively coarse meshes are sufficient to obtain accurate estimates of stress intensity factors by a direct displacement method not requiring an extrapolation process.

Name dc:type.qualificationname

Doctoral Thesis

Level dc:type.qualificationlevel

Student thesis

Grantor dc:publisher.institution

Polytechnic of Wales

Year dc:date.issued

1980

Author dc:creator

• Sabir, Bahir

Language dc:language

eng

Identifier

oai:pure.atira.dk:studenttheses/887406f9-6b9c-4150-b9de-b8177c519710

OAI identifier oai:identifier

oai:pure.atira.dk:studenttheses/887406f9-6b9c-4150-b9de-b8177c519710