As part of the United States Marine Corps (USMC) Mitigation of Blast Injuries through Modeling and Simulation project, Protection Engineering Consultants investigated and compared a range of landmine modeling strategies in LS-DYNA. Dividing the constituent materials into solids (soil) and fluids (air and explosive burn products), various numerical formulations were applied to the two groups in different combinations. Single-formation strategies included a traditional all-ALE approach and a less conventional all-SPH approach. Hybrid formulation strategies included combinations of ALE fluid and explosive materials with FEM, DEM, or SPH soil. The various single-formulation and hybrid-formulation are compared in terms of implementation, required coupling definitions, stability issues, calculation demands, and overall feasibility.
The quantitative performance of three front-runner strategies were compared against benchmark test data. Evaluation cases included initial soil bubble formation, scaled-test impulses against flat plates, scaled-test impulses against angled plates, and full-scale impulses against flat plates. The benchmark tests used sandy soils at varying levels of saturation.
A generalized sandy soil modeling approach was used to generate parameters for the Pseudo Tensor material model and the Tabulated Compaction equation of state. The average error for predicted impulse was less than 2.5%, which was obtained from the generalized soil model using a priori material parameter settings and without post hoc tuning.