Simulation of blast-loaded aluminium plates with crack-like defects

Abstract

This paper presents a numerical study on the response of blast-loaded AA6016 T4 aluminium plates with crack-like defects. Explicit finite element simulations were performed with LS-DYNA, using an uncoupled plasticity and fracture model with throughthickness damage regularization valid for shell elements. Uniaxial tensile tests are used to determine the parameters of the constitutive model by inverse modelling. Four different crack-like defects are considered at a load level resulting in failure and crack propagation in all the plates. The simulation results obtained with different mesh sizes are evaluated against experiments conducted in a shock tube facility. The shell element model is able to predict failure and crack propagation with good accuracy for the finest mesh, i.e., shell elements with length-to-thickness ratio of 1/3, while the accuracy decreases rapidly as the mesh size is increased.