| Autor: |
Iliopoulos, Sokratis, Polyzos, Demosthenes, Angelis, Dimitrios |
| Přispěvatelé: |
Mechanics of Materials and Constructions |
| Jazyk: |
angličtina |
| Rok vydání: |
2015 |
| Předmět: |
|
| Popis: |
The propagation of longitudinal ultrasonic waves through fresh and hardened concrete is strongly affected by dispersion and this is clearly indicated experimentally from the change of phase velocity at low frequencies. Analytically, only few attempts have been made to explain this dispersive behavior through enhanced elastic theories. The most commonly used higher order theory is the strain gradient elastic theory which takes into account the microstructural effects in heterogeneous media like concrete. These microstructural effects are described by two internal length scale parameters (g and h) which correspond to the micro-stiffness and micro-inertia respectively. In the current paper, it is shown that Mindlin’s gradient theory explains sufficiently the experimentally observed velocity dispersion of the fresh and hardened material sharing different water to cement ratios or sand contents while it is able to inform on concrete’s phase change through the monitoring of the relative difference of the g and h values. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
|
