Fluid pressurization in articular cartilages and menisci plays an important role in the mechanical function of the knee joint. However, fluid pressure has not been incorporated in previous finite element modelling of the knee, instead elastic models of the knee are widely used. It is believed that an elastic model can be used to predict the instantaneous load response of the knee as long as lar...

an analytical nonlinear stress-strain model and a microscopic damage index for confined and unconfined concretes together with a macroscopic damage index for reinforced concrete (rc) structures under cyclic loading are proposed. in order to eliminate the problem of scale effect, an adjustable finite element computer program was generated to simulate rc structures subjected to cyclic loading. by...

Realistic finite element modelling and simulation of neurosurgical procedures present a formidable challenge. Appropriate, finite deformation, constitutive model of brain tissue is a prerequisite for such development. In this paper, a large deformation, linear, viscoelastic model, suitable for direct use with commercially available finite element software packages such as ABAQUS is constructed....

The stiffness of articular cartilage is a nonlinear function of the strain amplitude and strain rate as well as the loading history, as a consequence of the flow of interstitial water and the stiffening of the collagen fibril network. This paper presents a full investigation of the interplay between the fluid kinetics and fibril stiffening of unconfined cartilage disks by analyzing over 200 cas...

Unconfined compression tests are more convenient to perform on cylindrical samples of brain tissue than tensile tests in order to estimate mechanical properties of the brain tissue because they allow homogeneous deformations. The reliability of these tests depends significantly on the amount of friction generated at the specimen/platen interface. Thus, there is a crucial need to find an approxi...

Mechanical behavior of articular cartilage was characterized in unconfined compression to delineate regimes of linear and nonlinear behavior, to investigate the ability of a fibril-reinforced biphasic model to describe measurements, and to test the prediction of biphasic and poroelastic models that tissue dimensions alter tissue stiffness through a specific scaling law for time and frequency. D...

The aim of the presented study is to identify some properties of the dynamic behavior of the cancellous bone and to identify the link between this mechanical behavior and the microstructural properties. 7 cylinders of bovine cancellous bone (diameter 41 mm, thickness 14 mm) were tested in quasi static loading (0.001 s), 8 in dynamic loading (1000 s) and 10 in dynamic loading (1500 s) with a con...

Knee articular cartilage exhibits complex mechanical behavior, even under high strain rates, which poses a challenge to developing accurate and efficient cartilage models. In particular, the tissue's stress–strain response is non-linear and the stiffness of the response is location-dependent. Hyperelastic models such as those of Alan Gent and others have increasingly found use in soft tissue bi...

The tensile modulus of articular cartilage is much larger than its compressive modulus. This tension-compression nonlinearity enhances interstitial fluid pressurization and decreases the frictional coefficient. The current set of studies examines the tensile and compressive properties of cylindrical chondrocyte-seeded agarose constructs over different developmental stages through a novel method...