Sökning: "Rate-dependent models"

Visar resultat 1 - 5 av 16 avhandlingar innehållade orden Rate-dependent models.

1. 1. On cyclic accumulation models for degradation of railway foundations

   Författare :Hossein Tahershamsi; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Natural soft clay; Global Sensitivity Analysis; Sobol method; Experimental design; Rate-dependent models; Cyclic accumulation models; Cyclic degradation; Uncertainty analysis;

   Sammanfattning : The degradation of railway foundations due to the repeated loading of traffic induces maintenance and safety obligations for the track operator. One major contributor to track degradation is the accelerated settlement rates in soft soils below the track that lead to alignment issues, especially at stiffness transitions. LÄS MER

3. 2. Continuum modeling of paperboard for the mechanical response of converting processes

   Författare :Kristofer Robertsson; Hållfasthetslära; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Paperboard; Continuum modeling; Converting processes; FEM simulations; Finite strain theory; Damage modeling; Rate-dependent; Creasing and folding; Out-of-plane experiments;

   Sammanfattning : Paperboard is a thin and lightweight material made of cellulose fibers and it is an important component in packaging material where it provides stiffness and rigidity. The scope of this work is the development of continuum models, and its numerical treatments, for simulating the processes of converting paperboard into packages. LÄS MER

4. 3. Topology optimization of non-linear, dissipative structures and materials

   Författare :Niklas Ivarsson; Hållfasthetslära; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Topology optimization; Stiffness optimization; Finite strain; Rate-dependent plasticity; Discrete adjoint sensitivity analysis;

   Sammanfattning : Topology optimization is a mathematical tool for finding optimal distributions of material phases within a design domain. It is commonly used in early design stages to generate conceptual structural layouts. Ultimately, designs generated by topology optimization consist of distinct material phases with enhanced performance. LÄS MER

5. 4. Development of Energy-based Damage and Plasticity Models for Asphalt Concrete Mixtures

   Författare :Ibrahim Onifade; Björn Birgisson; Linbing Wang; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; energy-based models; damage; X-ray computed tomography; continuum plasticity mechanics CPM; effective micro-crack stress; Transportvetenskap; Transport Science;

   Sammanfattning : Characterizing the full range of damage and plastic behaviour of asphalt mixtures under varying strain-rates and stress states is a complex and challenging task. One reason for this  is partly due to the strain rate and temperature dependent nature of the material as well as the variation in the properties of the constituent materials that make up the composite asphalt mixture. LÄS MER

7. 5. Modeling of Elasticity and Damping for Filled Elastomers

   Författare :Per Erik Austrell; Byggnadsmekanik; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; rheological models; contact-free strain measurement; modified hardness test; solid dumbbell test specimen; mechanical conditioning; strain energy plot; hyperelasticity; carbon-black-filled rubbers; amplitude dependence; multiaxial viscoplastic model; Building construction; Byggnadsteknik;

   Sammanfattning : Elasticity and damping are significant properties of rubber, taken advantage of in engineering applications. It is therefore important that the constitutive model accurately captures these aspects of the mechanical behavior. LÄS MER