The goal of this study was to determine the duration of time that ligaments from a study group need to be loaded in order to adequately determine their collective viscoelastic behavior. Rat ligaments were subjected either to creep or stress relaxation for 1,000 s or stress relaxation for 10,000 s to compare estimates of viscoelastic behavior for different test durations. Stresses versus time (r...

Trabecular bone has been previously recognized as time-dependent (viscoelastic) material, but the relationships of its viscoelastic behaviour with bone volume fraction (BV/TV) have not been investigated so far. Therefore, the aim of the present study was to quantify the time-dependent viscoelastic behaviour of trabecular bone and relate it to BV/TV. Uniaxial compressive creep experiments were p...

Motivated by recent progress in viscoelastic indentation analysis, the identification of viscoelastic properties from materials exhibiting elastic, viscous and plastic material behaviour by means of nanoindentation is dealt with in this paper. Based on existing solutions for pure viscoelastic material behaviour, two methods allowing us to consider the effect of plastic deformation are presented...

The nonlinear dynamic response of thin plates made of linear viscoelastic material of fractional derivative type is investigated. The resulting governing equations are three coupled nonlinear fractional partial differential equations in terms of displacements. The solution is achieved using the AEM. According to this method the original equations are converted into three uncoupled linear equati...

It is well known that there are wide varieties of materials which form self-organized structure. When a sort of 3 dimensional network structure is formed, the system may possess viscoelastic properties similar to entangled polymers or gels depending on life time and strength of the structure. A typical example of low molecular weight system is wormlike micelles formed in aqueous solutions of su...

Introduction Tendons are hierarchical fibre composite materials, designed for the efficient transfer of force from muscles to the skeleton, and thus displaying high tensile strength, as well as complex viscoelastic and anisotropic characteristics [1] . Although the gross viscoelastic behaviour of tendon has received considerable attention, the mechanisms by which the tissue structure facilitate...

Associate Professor, Graduate Aeronautical laboratories, California Institute of Technology, Pasadena, Calif. The tip velocity of a crack propagating through a vi scoelastic material depends on geometry, apptied toad and its history , and material properties. A consideration of the work done by the unloading tractions at the crack tip shows that, f or a large crack propagating throitgh an infin...

AIM OF THE STUDY To compare and estimate the safety and efficacy of a new viscoelastic substance combined with anaesthetic used in phacoemulsification surgery. METHOD Eight hundred seventy-four patients observed at the Department of Ophthalmology and the Department of Family Medicine of the General State Hospital of Nikea-Piraeus (Greece) submitted to a phacoemulsification surgery for catarac...

Simulation of a large number of deformable bodies is often difficult because complex high-level modeling is required to address both multi-body contact and viscoelastic deformation. This necessitates the combined use of a discrete element method (DEM) and a finite element method (FEM). In this study, a quadruple discrete element method (QDEM) was developed for dynamic analysis of viscoelastic m...