A hybrid approach to determining cornea mechanical properties in vivo using a combination of nano-indentation and inverse finite element analysis approach. A validation experiment using nano-indentation showed that an isotropic GM model was insufficient for describing the corneal material behaviour when exposed to a complex stress state. A new technique was proposed for determining the properties, using a combination of nano-indentation experiment, an isotropic and orthotropic GM model and inverse finite element method. The good agreement using this method suggests that this is a promising technique for measuring material properties in vivo and further work should focus on the reliability of the approach in

This paper investigates different approximation techniques for planar beam column elements in force-based methods. The three fields, introduced in this review, are: curvature-based displacement interpolation (CBDI) used in matrix-based flexibility formulations, linear displacement approximation applied in state space, and higher-order displacement approximation utilized again in state space. Using these three approximation fields, the responses and their accuracies in some systems are compared in examples. Finally, focusing on the accuracy and regarding the performed analyses, it seems that the computational cost is reduced and accuracy of responses is elevated in many engineering problems using the higher-order approximation field in state space.

An increase in interfacial properties between the matrix, a polyurethane cellular foam, and the reinforcement, a short carbon fibre, led to improved mechanical properties of a lightweight composite. The carbon fibre surface modification was designed with two aims: to impart magnetic properties so the discontinuous fibres could be aligned on-demand during the manufacturing process using a weak magnetic field, and to promote interfacial adhesion between the matrix and the reinforcement. After surface treatment, functionalising and coating with magnetite nanoparticles created and deposited in situ via electrodeposition prior to their deployment, the fibres were susceptible to magnetic manipulation and orientation within the reacting foam. The fibre coating contributed to interfacial compatibilization between the matrix and the reinforcement. Comparing the results between unreinforced, reinforced with untreated fibre, and reinforced with magnetised fibre, the results show that: foam reinforced with a low %vol content, i.e., from 0.1%vol to 0.4%vol, of any of the fibres improved specific strength, stiffness and toughness in tension relative to the unreinforced cellular polymeric matrix without densification, modification of cell size or compromising their lightweight properties. The magnetised fibre-containing composites showed significantly improved mechanical properties overall in tension, when compared to the untreated fibres, due to their enhanced interfacial adhesion and their alignment in the matrix. Results in compression yielded improvement only in compressive strength, with other properties being similar to the unreinforced matrices. No significant differences were observed between the magnetised (aligned fibres) and the untreated (randomly distributed) configurations in compression.