The risk of extreme damage to critical facilities by attacks from terrorists or disgruntled employees combined with process risks is becoming a major factor in the design. The approach suggested by extant practices and guides with this regard has evolved into a pseudo-design methodology involving missing columns and "tie force" designs and detailing. Very different design concepts are needed to analyze structures that are highly damaged or have failed completely. The New Design Paradigm focuses on component design of critical building elements using a threat dependent, performance based methodology using high-fidelity physics-based (HFPB) finite element codes that capture actual material and component response. One of these is LS-DYNA developed by Livermore Software Technology Center. To counter the difficulty, expense and high degree of skills needed for use of HFPB codes one approach is to develop and use a library of Fast Running Models (FRM's) which interrogate a database of virtual HFPB response data for given components and loading. These FRMs can be rapidly and easily run on desk top computers and can provide access to a domain of solutions far outside the capability of simplified engineering tools for a range of loading scenarios such as air blast loading from high-explosive detonations, vapor cloud explosions and primary and secondary fragmentation. Component design using HFB codes and FRMs for speed and economy of analysis will provide a far more meaningful analysis for blast effects, including disproportionate collapse than simplified methods advocated in the Unified Facilities Criteria (UFC) and similar design guidance documents.
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