Evaluation of Alternate Roof-Wall Details for the Keyworker Blast Shelter

Abstract : At the time this study was initiated, several civil defense policy options were being analyzed for protection of the nation's industrial capability and key workers. One option under consideration called for construction of blast shelters to protect key workers remaining in high-risk areas during a national crisis. In support of this option, the Federal Emergency Management Agency (FEMA) tasked the US Army Engineer Division, Huntsville (HND), to develop Keyworker shelter designs. The design required an earth-covered shelter to resist the radiation and blast effects of a 1-MT nuclear detonation at the 50- psi peak overpressure level. Personnel in the Structures Laboratory of the US army Engineer Waterways Experiment Station (WES) supported HND with design calculations and design verification experiments. In the construction of a large number of shelters, it is important that the shelter design provide the required structural capacity at reasonable costs. The original roof-wall reinforcement detail created a constructibility problem that increased construction costs. The objective of the experimental program described in this report was to evaluate alternate roof-wall joint details for the Keyworker blast shelter in an effort to improve constructibility without reducing structural capacity.