Finite element modelling of orthotropic material behaviour in pneumatic membranes

Effect of reinforcement volume fraction and orientation on a hybrid tissue engineered aortic heart valve with a tubular leaflet design

“…This section describes first the structural tensor material model adapted from Reese et al [17] to describe the fiber-reinforced tissue under large deformation. Next, the material characterization is briefly summarized, and finally the boundary conditions of the model are defined.…”

“…However, the magnitudes near the bottom suture and the corner stitch should be considered suspect and useful for more of a qualitative rather than quantitative comparison. For the (17) Fig. 9 Elemental convergence study for heart valve with no fiber reinforcement; a average error at the leaflet centerline and b maximum principle strain distribution in the valve.…”

“…The model chosen for this particular study is based on the model first proposed by Reese et al [17] and further developed and/or applied in [18][19][20]. The fiber directions are captured through so-called structural tensors, and the matrix is represented by a hyperelastic Neo-Hookean model.…”

Effect of Fabric Webs on the Static Response of Spindle-Shaped Tensairity Columns

“…Wielgosz and Thomas (2003) developed a Timoshenko beam finite element and predicted deflections along the span and wrinkling loads of inflatable fabric beams at high internal air pressure subjected to 3-point bending. Reese et al (2001) applied a hyperelastic material model for the fabric and developed a brick finite element for the coating and non-linear truss elements for the fibers to predict the static response of a membrane under pressure. Cavallaro et al (2003) developed unit cell models accounting for friction between crossing tows and studied the effect of material, air pressure and loading rate on the midspan deflection in airbeams subjected to 4-point bending.…”

An anisotropic viscoelastic fibre–matrix model at finite strains: Continuum formulation and computational aspects

“…In this latter, the authors have pursued Simo's constitutive framework [27] where the overstresses of each compound of the composite materials are chosen as internal variables which, in turn, are governed by linear differential equations in a form similar to that employed in linear viscoelasticity. In all these formulations, the anisotropic behaviour is, among others, captured by a particular choice of the free energy function formulated in terms of the so-called integrity basis as proposed by Spencer (1984) [31], and widely employed for purely elastic materials, see for example [1,22,34] to mention few.…”