Weapons Effects FRMs for Reinforced Concrete Walls & Floor/Ceiling Slabs

A 24 month SBIR Phase II Project is proposed to develop weapons effects fast-running models (FRMs) for reinforced concrete walls and floor/ceiling slabs in hardened bunker-type structures. The objective is to develop High-Fidelity Physics-Based (HFPB) fast-running models (FRMs) for simulating the effects of air-delivered weapons on heavily reinforced concrete walls and floor/ceiling slabs. The hardened structure FRM will include walls and floor/ceiling slabs for bunkers constructed of normal to ultra high-strength concrete (UHSC), realistic bunker layouts, and current and future weapons ranging from the Small Diameter Bomb (SDB) to the Massive Ordnance Penetrator (MOP). FRMs are also required for predicting breach/spall and secondary debris-projection, i.e. debris throw. The secondary debris models will be used to extend the load parameter spaces for non-charge room wall/slabs. BENEFIT: The ability to model high-strength concrete is important for new hardened structures that will use HSC to combat the effects of new “bunker busting” weapons. The expansion of ARCWall to include weapons ranging up to the MOP, along with the incorporation of HSC in ARCWall will benefit the Air Force by enabling the assessment of damage to new bunker construction subjected to new weapons of the foreseeable future. MOP-type weapons will likely affect more than just the charge room in a typical bunker. The new version of ARCWall will model hallways and outer rooms of a typical bunker. The proposed innovation for modeling concrete damage will enable the direct modeling of holes in breached walls so that the venting of gasses from one room to another can be more accurately modeled. Stochastic debris cloud models will allow the stochastic modeling of individual fragment clouds where the mass, and velocity components of the individual fragments are properly correlated, based on HFPB modeling.