Sökning: "viscoelastic measurements"
Visar resultat 1 - 5 av 52 avhandlingar innehållade orden viscoelastic measurements.
Sammanfattning : Two system identification problems, identification of viscoelastic material properties and identification of continuous-time stochastic systems, are considered in the thesis. The viscoelastic material properties are characterised by the frequency-dependent complex modulus. LÄS MER
2. Estimation of state and identification of complex modulus based on measurements om a bar traversed by waves
Sammanfattning : Estimation of state and identification of complex modulus based on measurements on non-uniform rods and beams have been studied theoretically and experimentally. Two principal cases were studied. In the first case, the material properties are fully known and the state at a section is to be estimated. LÄS MER
3. Mechanistic-Empirical Modelling of Flexible Pavement Performance : Verifications Using APT Measurements
Sammanfattning : Mechanistic-Empirical (M-E) pavement design procedures are composed of a reliable response model to estimate the state of stress in the pavement and distress models in order to predict the different types of pavement distresses due to the prevailing traffic and environmental conditions. One of the main objectives of this study was to develop a response model based on multilayer elastic theory (MLET) with improved computational performance by optimizing the time consuming parts of the MLET processes. LÄS MER
Sammanfattning : The viscoelastic behaviour of biopolymer mixtures showing synergism was investigated under different physicochemical conditions using small deformation oscillatory measurements. In addition, the rheological properties of binary polysaccharide mixtures were related to the microstructure as observed using transmission electron microscopy. LÄS MER
5. Determination of viscoelastic material properties and impact force from measurements on impacted bodies
Sammanfattning : Methods are presented for identification of linear and nonlinear viscoelastic materials and for prediction of impact force on the basis of measurements made on impacted bodies. The complex modulus is identified from measured end-point accelerations of an impacted rod specimen, and in-situ from measured strains at three sections of a rod-like member of an impacted structure. LÄS MER