Validation of a Loading Model for Simulating Blast Mine Effects on Armoured Vehicles

An ongoing program at Defence R&D Canada to reduce the vulnerability of Light Armoured Vehicle (LAVs) to anti-vehicular blast mines is relying heavily on LS-DYNA to help design and optimize add-on armour systems. A significant challenge in the numerical modelling work is the development of an accurate, or at least representative, loading history for the pressure and momentum transfer from the detonation of a buried blast mine. Arbitrary Lagrange-Eulerian (ALE) techniques offer some promise but the analysis is very computationally intensive. Another option that is more attractive from the point of view of simplicity (implementation and computation time) is an empirically based loading model. The LS-DYNA implementation of the CONWEP blast equations (*LOAD_BLAST) is one such example. While some authors have used this model to predict the effects of mine blasts on vehicle structures, there are significant limitations in this model. A more advanced empirical model for predicting the effects of blast mines on structures was developed for the U.S. Army Tank Automotive Command (TACOM) by Southwest Research Institute. This model has been implemented by the Defence R&D Canada - Valcartier (DRDC - Valcartier) in a pre-processor for LS-DYNA. A parameter study has been conducted using this implementation of the impulse model and the results are compared to those obtained from the CONWEP blast model. Validation is based on a series of experiments conducted at DRDC - Valcartier using square aluminium and steel test panels subjected to detonations of buried charges (surrogate mines) of 6 kg of C-4 explosive.