Abstract:
The PhD Thesis entitled Experimental investigations and
numerical simulations of the mechanical behaviour of polyamides
deals with the analysis of the behaviour of a PA-12 based
polymer that has applications in sports footwear components.
The mechanical properties of this material were investigated for
various loading scenarios, results being used in designing virtual
material models for finite element analysis simulations. The
thesis is structured in 5 chapters. The first chapter consists of the
thesis introduction, presenting the research background, the
state of the art and the objectives. The second chapter presents
the experimental procedures and the obtained results for tensile
loadings (monotone tests, cyclic tests, low-cycle fatigue tests),
three-point bending tests, dynamic tests (dynamic tension, DMA
tests, puncture impact tests) and for compression tests
performed on footwear components. In the third chapter several
analytical models for describing constitutive relations were
presented: linear elasticity, hyperelasticity, plasticity and
viscoelasticity. The fourth chapter presents the results for
simulations performed on three constitutive formulations: an
elasto-plastic model, a hyperelastic model and a viscoelastic
model. The constitutive models were evaluated for several test
scenarios (monotone tension, cyclic tension and three-point
bending) and validated on component simulations. The fifth
chapter presents the conclusions and the personal contributions.