Frost Engineering & Consulting was enlisted to analyze document storage rack systems in The National Archives and Records Administration’s Federal Records Center in Missouri. The center is in an excavated limestone cave, 60 ft. below the surface. Frost was tasked with developing a safe methodology for raising individual rack posts in order to level existing rack systems without needing to unload those documents already being stored.
After running several iterations of finite element models with imposed displacements specified by the client, Frost determined that the intended displacement would cause fracture in primary bracing elements in the rack system. In support of the client, Frost proposed multiple alternative solutions, including raising multiple posts simultaneously to reduce relative strain concentration, installing enhanced bracing in the overstressed locations, and scoped out a physical validation test.