1 Δεκεμβρίου 2021
|11:00 - 12:20||
Buckling, restabilization and dynamics of extremely deformable structures subject to configurational forces
The concept of configurational (material) force has been introduced by Eshelby to describe the motion of massless (voids, microcracks, vacancies, or dislocations) or heavy (inclusions) defects within a solid body as the result of mechanical or thermal loading. This concept has been exploited through the years for modelling the crack-driving force in fracture mechanics, the Peach–Koehler force of dislocations, or the material force developing on a phase boundary in a solid under loading. In the present work, the action of configurational forces on elastic structures are theoretically and experimentally proven in the presence of a specific movable constraint: a frictionless, perfectly smooth and bilateral sliding sleeve. Intriguing mechanical behaviours are disclosed for compliant structural systems involving configurational constraints. The following cases will be examined: (i) An elastic rod constrained by a frictionless sliding sleeve ending with a linear spring and subject to a dead load at the other end, (ii) The sudden release of a rod with a concentrated weight attached at one end and partially inserted into a frictionless sliding sleeve at the other and (iii) The periodic oscillation of a configurational constraint during the fall of a rod. The results represent innovative concepts in mechanics to be used in advanced applications, as for example in actuation mechanisms, energy harvesting, vibration mitigation, shock absorbers.
Francesco Dal Corso
Αναπληρωτής Καθηγητής στο University of Trento, Italy