Munition penetration-depth prediction : SERDP SEED Project MR-2629

Existing models for predicting the penetration depth of munitions and explosives of concern are inaccurate and insufficient from a user (range manager, U.S. Army Corps of Engineers project manager, or environmental consultant) operability perspective for current needs. We attribute poor model performance to (1) a heavy dependence on empirically derived parameterizations poorly linked to the physical properties of the target material or (2) physics-based models that inadequately capture the salient mechanical processes, especially in the first meter of penetration. Consequently, we have developed a micromechanical-based model using a hybrid discrete element model (DEM) / finite element model (FEM) approach capable of a detailed treatment of near-surface soil properties. To examine the effects of varying levels of moisture on the dynamic behavior of a soil, we fabricated a small-scale triaxial shear test to inform the development and calibration of the DEM contact model. We conducted projectile-drop tests into sand with a scale version of a 57 mm projectile and measured projectile penetration to compare with model results. DISCLAIMER: The contents of this report are not to be used for advertising, publication, or promotional purposes. Citation of trade names does not constitute an official endorsement or approval of the use of such commercial products. All product names and trademarks cited are the property of their respective owners. The findings of this report are not to be construed as an official Department of the Army position unless so designated by other authorized documents. DESTROY THIS REPORT WHEN NO LONGER NEEDED. DO NOT RETURN IT TO THE ORIGINATOR. ERDC/CRREL TR-17-12 iii

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