By using of combining theoretical model with empirical model, the nonlinear viscoelastic-plastic constitutive equations of soybean and cottonseed were developed on the basis of the creep test. The parameter inverse problem of constitutive model was proposed using improved particles swarm optimization. Numerical simulations of creep of soybean and cottonseed were carried out. The definition of c...

This paper presents chaotic behavior of a nonlinear viscoelastic beam under a moving mass interaction. Considering the stretching effect which is modeled by the Lagrangian strain theory and using linear Kelvin-Voigt model to constitute viscoelastic behavior of the beam, the governing equations of transverse vibration is derived. Then Galerkin truncation is applied to find the ordinary different...

A chondrocyte and its surrounding pericellular matrix (PCM) are defined as a chondron. Single chondrocytes and chondrons isolated from bovine articular cartilage were compressed by micromanipulation between two parallel surfaces in order to investigate their biomechanical properties and to discover the mechanical significance of the PCM. The force imposed on the cells was measured directly duri...

Large balloon structures are made of thin anisotropic polymeric film that shows considerable time-dependent material behaviour. While the material has been fully characterised and a detailed time-dependent material description by means of a nonlinear viscoelastic Schapery material model is available, there is no suitable numerical implementation for finite element analysis. This paper presents ...

In a material consisting of graphene oxide or reduced graphene oxide and poly-N-isopropylamide (PNIPAM) in an aqueous solution, a new type of rheological behaviour is found. When subjecting the material to a short and relatively small deformation pulse, the modulus, which is observed by small deformations in the linear-viscoelastic or very slightly nonlinear range, oscillates with periodicities...

This paper presents an Abaqus/Explicit simulation of the impact event when a golf club hits a golf ball. This is a challenging subject for finite element simulations because of it is characterized by high strain rate behavior. The simulation emphasizes accurate material characterization and realistic model construction. Specifically, an advanced nonlinear viscoelastic material model from Veryst...

We study the blow-up of the solution to a quasilinear viscoelastic wave system coupled by nonlinear sources. The system is of homogeneous Dirichlet boundary condition. The nonlinear damping and source are added to the equations. We assume that the relaxation functions are non-negative non-increasing functions and the initial energy is negative. The competition relations among the nonlinear prin...

In vivo measurements of the viscoelastic properties of breast tissue are described. Ultrasonic echo frames were recorded from volunteers at 5 fps while applying a uniaxial compressive force (1-20 N) within a 1 s ramp time and holding the force constant for up to 200 s. A time series of strain images was formed from the echo data, spatially averaged viscous creep curves were computed, and viscoe...

This paper develops a model for evolving wrinkles in a bilayer thin film consisting of an elastic layer and a viscoelastic layer. The elastic layer is subjected to a compressive residual stress and is modeled by the nonlinear von Karman plate theory. A thin-layer approximation is developed for the viscoelastic layer. The stability of the bilayer and the evolution of wrinkles are studied first b...

Using a picosecond pump-probe ultrasonic technique, we study the propagation of high-amplitude, laser-generated longitudinal coherent acoustic pulses in the viscoelastic fragile glass former DC704. We observe an increase of almost 10% in acoustic pulse propagation speed at the highest optical pump fluence which is a result of the supersonic nature of nonlinear propagation in the viscous medium....