Experimental verification of similarity laws for impacted structures made of different materials

Autor(es)

Mazzariol, Leonardo M. ^{[1, 2]} ; Alves, Marcilio ^[1]

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo, Grp Solid Mech & Struct Impact, Dept Mechatron & Mech Syst Engn, BR-05508900 Sao Paulo - Brazil

^[2] Fed Univ ABC, Engn Modeling & Appl Social Sci Ctr CECS, BR-09210580 Santo Andre, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: INTERNATIONAL JOURNAL OF IMPACT ENGINEERING; v. 133, NOV 2019.
• Citações Web of Science: 1

Resumo

Recent developments of similarity laws for impact have focused on approximated methods of distorting impact velocity to overcome strain-rate effects and differences in material mechanical properties. Although many advances were proposed, all studies lack comprehensive experimental tests to corroborate the theoretical propositions. The present study shows an experimental verification of these scaling laws, using three different scales, three different materials and two loading cases. The chosen materials have differences in density, material mechanical properties and a small thickness distortion. An extensive material characterisation program was conducted. Tested structures comprise circular plates, impacted in its centre by a low velocity indenter or a high velocity projectile. Both initial velocity and impacted mass are calculated using scaling factors based on the material properties. In addition, numerical simulations are performed to assess the behaviour of these models and extract informations such as deformed profile at maximum displacement and strain-rate history. Displacements and force response results have shown that differences in density, material mechanical properties as well as thickness distortions can be compensated by respecting dimensionless quantities based on mass ratio and on plastic bending moment. However, care must be taken when choosing model material ductility so as to avoid that failure strain is reached, as here discussed. Furthermore, the influence of viscoplasticity effects in these scaled structures are shown to be small when compared to other quantities such flow stress scaling factor and/or thickness distortion. (AU)

• Processo FAPESP: 14/03135-7 - Representação de estruturas sujeitas a cargas de impacto através de modelos escalonados: estrutura e modelo feitos de materiais diferentes
• Beneficiário: Leonardo Monteiro Mazzariol
• Modalidade de apoio: Bolsas no Brasil - Doutorado