This paper describes the development of a point-loaded, centre-cracked (P.L.C.C.) plate in fracture studies. The methods used to determine a satisfactory geometry for the specimen, in terms of the stability of cracking, are discussed, and the results agreed well with those obtained experimentally. The stress intensity factor (KI) of the plate is presented for a wide range of H/W values, using a finite-element method based on a displacement-function approach. Fracture-toughness (Gc) tests, involving the use of a quasistatic energy concept, are conducted and used to check the accuracy of the computed KI-values. Good correlation is obtained between the stress and energy approaches.
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