23 documents found, page 1 of 3

Experiment and modelling of the strain-rate-dependent response during in vitro ...

Polylactic acid (PLA) fibres present, in their pristine state, a strain-rate-dependent behaviour. Their mechanical properties evolve during in vitro biodegradation. Tensile tests of PLA fibres are performed at five different strain rates 0.0001, 0.001, 0.01, 0.05 and 0.1/s and at seven degradation stages, 0, 20, 40, 60, 90, 120 and 150 days in a phosphate buffer solution at constant temperature at 37 degrees C....

PARTIALLY ENCASED COLUMNS EMBEDDED ON WALLS UNDER FIRE

Ultra high molecular weight polyethylene and its reinforcement with Carbon Nano...

This chapter discusses the advantages and complexities of ultra high molecular weight polyethylene (UHMWPE) when used as a bearing material for total joint arthroplasty (TJA) and total knee arthroplasty (TKA). The UHMWPE internal structure and its mechanical response depend strongly on a diversity of factors that include radiation crosslinking, fiber reinforcement, and the addition of antioxidants such as Vitam...

Stress-strain analysis of specimens subjected to tensile loading during moistur...

Abstract: A robust and efficient numerical method for the calculation of the internal stress state that develops within structures subjected to mechanical and steady state or transient hygroscopic loading conditions, has been developed. The method encompasses a layer by layer approach whereby the structure is discretised into plies with different material properties corresponding to the different ply moisture c...

Constitutive modeling and mechanical behavior prediction of biodegradable polym...

A large range of biodegradable polymers has been used to produce implantable medicaldevices, such as suture fibers, fixation screws and soft tissue engineering devices. Apartfrom biological compatibility, these devices should also be functional compatible andperform adequate mechanical temporary support during the healing process. Themechanical behavior of biodegradable polymers is known to be rate dependent an...

4D Numerical Analysis of Scaffolds: A New Approach

A large range of biodegradable polymers are used to produce scaffolds for tissue engineering, which temporarily replace the biomechanical functions of a biologic tissue while it progressively regenerates its capacities. However, the mechanical behavior of biodegradable materials during its degradation, which is an important aspect of the scaffold design, is still an unexplored subject. For a biodegradable scaff...

Creep Design of Piping Applications using Composites

The effect of carbon nanotubes on viscoelastic behaviour of biomedical grade ul...

Nanocomposites of ultra-high molecular weight polyethylene reinforced with multiwalled carbon nanotubes (UHMWPE/MWCNT) have been prepared with different volume fractions of MWCNTs: 0.2, 0.4, 0.6, 0.8 and 1.0%. DMTA experiments were carried out using a TA Instruments Q800 equipment and the samples were cut from the compressed sheets of polymer and composites. The experiments were conducted on each sample at 12 d...

Understanding and predicting stiffness in advanced fibre-reinforced polymer (FR...

This chapter describes the elastic qualities of advanced fibre-reinforced composites, in terms of characterization, measurement and prediction from the basic constituents, i.e. the fibre and matrix. The elastic analysis comprises applying micromechanics approaches to predict the lamina elastic properties from the basic constituents, and using classical lamination theory to predict the elastic properties of comp...

A simple and effective scheme for data reduction of stress relaxation incorpora...

A simple methodology for obtaining viscoelastic parameters from the stress relaxation tests incorporating physical-aging effects is presented. The method assumes that the experimental data are in the linear viscoelastic domain. Three different mathematical representations of the viscoelastic stress relaxation modulus are analysed and used. Experimental data obtained from literature and simulated data with a ran...