Longitudinal Fracture of Inhomogeneous Viscoelastic Beams Subjected to Combined Time-Dependent Loading: A Parametric Study

A parametric study of longitudinal fracture in continuously inhomogeneous viscoelastic beam structures subjected to combined time-dependent loadings is described in this paper. The beams are under angle of twist and vertical displacement which change continuously with time. Beams with different cross-sections (T-shape, I-shape, trapezium, and rightangled triangle) are considered in order to assess the influence of the beam cross-section on the longitudinal fracture. The viscoelastic behaviour under bending and torsion is treated by using time-dependent modulus of elasticity and shear modulus, respectively. A viscoelastic mechanical model with two springs and a dashpot under time-dependent strains is used in order to derive the time-dependent moduli. These moduli are applied when obtaining solution of the strain energy release rate. The compliances of the beam configuration under time-dependent angle of twist and vertical displacement are analyzed in order to derive the strain energy release rate for verification. The parametric study is carried-out by using the solution of the strain energy release rate.