Non-linear Viscoelastic Beams Under Periodic Strains: An Approach for Analyzing of Longitudinal Fracture

This work describes a longitudinal fracture analysis of beam structure of circular cross-section under periodic strains. The material whose properties vary in radial direction has non-linear viscoelastic behaviour. The beam is loaded in torsion so that the twist angle represents a periodical function. Time-dependent behaviour under periodic strains is dealt with a model having a non-linear spring and a linear dashpot. The complementary strain energy in the beam is considered to determine the strain energy release rate. The balance of energy is examined to verify the strain energy release rate. The ascendency of various parameters over strain energy release rate is assessed.