A lattice discrete element method to model the falling-weight impact test of PMMA specimens

LUIS E. KOSTESKI; IGNACIO ITURRIOZ; ADRIÁN P. CISILINO; RICARDO BARRIOS D?AMBRA; VALERIA PETTARI´N; LAURA A. FASCE; PATRICIA FRONTINI

INTERNATIONAL JOURNAL OF IMPACT ENGINEERING

PERGAMON-ELSEVIER SCIENCE LTD

Lugar: Amsterdam; Año: 2016 p. 120 - 131

0734-743X

t is introduced in this paper a Lattice Discrete Element Method (LDEM) for modelling the fallingweighttest of polymethyl-methacrylate (PMMA) specimens. The method exploits the inherent characteristicsof discrete methods to model crack initiation and propagation by simply breaking the links between theirdiscrete components. It results in a flexible modelling tool that is implemented using Abaqus/Explicit.Numerical results are validated by comparison with experimental tests. The results are compared in termsof the time evolution of the striker force and velocity and the specimen crack patterns. The LDEM simulationsare, in every case, of predictive nature. Material properties are neither left open for calibrationnor used to adjust the numerical results. There is a good agreement between experimental and numericalresults. It is shown that the proposed LDEM has the capability to capture all the main features ofthe sequence of events that occur during the experiment: the elastic specimen loading prior to the crackinitiation, the nucleation and propagation of radial cracks as the test progresses, and the final failure afterthe rapid propagation of a circular crack that joins the radial cracks together. The effects of the variabilityof the material fracture toughness