A Two Parameter Approach to Elastic-Plastic Fracture Mechanics

Mechanical engineering, Mechanics

Nekkal, Abderrahmane

University:University of Glasgow

关键词: Mechanical engineering, Mechanics;   

Others  :  http://theses.gla.ac.uk/77276/1/10987053.pdf

来源: University of Glasgow

【 摘 要 】

The work presented in this thesis establishes techniques for the implementation of two parameter fracture mechanics. Two parameter fracture mechanics is based on the characterisation of elastic-plastic crack tip fields by the crack tip opening displacement (C.T.O.D) or equivalently by the J-contour integral introduced by Rice (1968), and the elastic T-stress which is the non-singular term in the Williams expansion (1957). In order to establish failure criteria in the form of a C.T.O.D-T fracture locus, it was necessary to design and analyse specimens which were capable of producing a range of T-stresses. An eccentrically loaded single edge crack bar was used to produce a range of bending to tension ratios on the ligament. Linear elastic finite element analyses established the relationship between the T-stress and the applied loading. Subsequent non-linear finite element analyses established techniques for the measurement of J and hence C.T.O.D.