Strength, stability and size effects in the brittle behaviour of bonded joints under torsion: theory and experimental assessment

Abstract

This paper describes a simple Griffith fracture energy criterion to predict the brittle failure load for tubular or non-tubular bonded joints subjected to torsion. The theoretical solution generalizes to non-tubular bonded joints an analogous result already presented in the literature and experimentally validated for particular tubular bonded joints. The stability of brittle crack propagation and the size effects on mechanical collapse behaviour, as well as the ductile-brittle transition, are analysed. Experimental measurements of failure loads under torsion for non-tubular bonded joints agree satisfactorily with the theoretical predictions.