Material point method and its application in different failure modes of grillage structure under penetration

The paper presents numerical investigations of 921A steel target plates impacted by truncated nosed alloy steel projectiles. The material point method is used to simulate and analyse the problem. Decohesion is an important failure mode to solve the fracture mode, because its constitutive equation is established to solve the local discontinuous fracture problem. The numerical results are in good agreement with the experimental results. The error of the break diameter is only 2.6% compared with the experimental data. The residual velocity agrees well with the experiment under six different conditions, and the error is less than 10%. The failure behaviour of the frame is similar to the actual situation, and the failure modes are almost the same. The penetration effects of different nosed projectiles are also compared, which verifies the conclusion that different contact forms lead to different failure modes. The results of this study show that MPM with decohesion can be well used to simulate the penetration problem.