Computational study of compact tension and double torsion test geometries

In the design of many engineering components subjected to cyclic or repetitive loading,fatigue is an ever-present challenge. The engineer often endeavors to design the structural or component system in such a way that the cyclic stresses are below a particular fatigue limit, or, in fracture mechanics terms, at stress levels below threshold. In the Paris formulation, fatigue threshold, Δҝₜₕ, may be regarded as that value of cyclic stress intensity below which fatigue crack growth does not occur. For a particular material and environment, this threshold value, Δҝₜₕ, is determined experimentally by monitoring growth of a crack (typically in a compact tension ( CT) specimen) and continually reducing cyclic stress levels until the threshold condition is reached. This procedure is very cumbersome and time-consuming, and this project rather considers the design of a fracture mechanics specimen geometry in which there is a decreasing stress in tensity (with crack length) that facilitates determination of the threshold value simply at constant applied cyclic amplitude, and the crack length at which fatigue crack growth arrests.

Grantor dc:publisher.institution

Department of Mathematics and Applied Mathematics

Year dc:date.issued

2014

Author dc:creator

• Goqo, Sicelo Praisgod

Advisors dc:contributor.advisor

• Daya, Reddy
• Tait, Robert
• Becker, Thorsten
• Skatulla, Sebastian

Language dc:language.iso

eng

Handle dc:identifier.uri

http://hdl.handle.net/11427/9108

OAI identifier oai:identifier

oai:open.uct.ac.za:11427/9108