Experimental study and modeling of polymer granular structures submitted to internal underpressure
Mariusz Pyrz , Robert Zalewski
AbstractThe paper deals with a system that consists of a granular material encapsulated in a tight, flexible envelope and submitted to an internal underpressure using a vacuum pump. It is found that the underpressure value has a considerable impact on the behavior and properties of the medium. Experimental studies and modeling of this phenomenon are provided in this work. Results of uniaxial tensile tests carried out on special cylindrical samples and characteristic hardening curves are presented for structures filled up with plastic grains. The nonlinear behavior of these materials is modeled using the viscoplastic constitutive Chaboche law, that requires the determination of several material parameters. The parameters identification problem is formulated as an optimization problem and solved by using an evolutionary algorithm. The numerically simulated graphs follow the experimental curves well. A modified version of Chaboche model, capable of capturing the polymer granular structure response to external loading and including underpressure parameter, is proposed. The presented methodology can be easily adapted to other constitutive models and experiments of special granular structures submitted to internal underpressure.
|Journal series||Mechanics of Materials, ISSN 0167-6636|
|Keywords in English||Granular material, Underpressure, Viscoplasticity, Experiments, Modeling, Evolutionary algorithm|
|ASJC Classification||; ;|
|Score|| = 40.0, 10-09-2019, ArticleFromJournal|
= 40.0, 10-09-2019, ArticleFromJournal
|Publication indicators||= 22; : 2013 = 1.721; : 2013 = 2.225 (2) - 2013=2.575 (5)|
* presented citation count is obtained through Internet information analysis and it is close to the number calculated by the Publish or Perish system.