Reliability-based design methods for protective structures

This paper summarizes the results of research to develop reliability-based design methods for use with the United States Air Force Protective Construction Design Manual (PCDM). The application of these methods is based on easy-to-use, reliability-based design factors (RBDFs). The research focused on five fundamental areas: (1) airblast and aboveground structure response; (2) groundshock and below-ground structure response; (3) fragmentation effects; (4) projectile penetration; and (5) protective structure systems reliability. The scope of the structural response research was limited to reinforced concrete structures; however, the load uncertainty analyses are generally applicable to protective structures of any material. The research also uncovered several areas of significant bias in the analysis methods, which could not be corrected without changes to the fundamental approach in the PCDM. RBDFs were not developed for these cases; however, either specific ways to improve the model prediction accuracy were recommended or improved models were provided and demonstrated.