Developing Rational and Efficacious Blast-Resistant Design Methodologies

Abstract

Development of a rational, standardized, and efficacious design methodology to produce blastresistant designs for structural systems, such as those desired for buildings, sports arenas, bridges, air terminals, and other types of commonly built structural systems does not seem likely to happen anytime soon. The need for protective designs has engendered a host of issues needing resolution, starting with the difficulty of obtaining such a methodology. The difficultly stems from a variety of issues that need resolution, and the unsettled and embryonic state-of-theart vis-a-vis protective design. Some of the key difficulties needing address are: the uncertainties related to defining suitable design basis threats and transforming them to design basis loads, the complexities of the structural behaviors likely to be involved for most realistic threats, and the difficulty of creating transparent and workable design methods for addressing them. The problem is further exacerbated and its resolution hampered by the absence of a governing agency or group with the charter, skills, funds, and organization to promulgate such a methodology. Efforts at developing a design methodology to date seem to be too biased toward simplicity and have too little of the rational, efficacious, and transparency aspects, and lack an over arching means to balance risk, likelihood, consequence, and cost with the development of new design technologies, methods, and engineering skills/tools that can work for a broad spectrum of risks and protection measures. This paper presents data to highlight some of the issues involved with developing such a design methodology, describing some of the elements and capabilities needed for both assessing the behaviors of an existing building’s structural system that are engendered by blast, and generating protective designs for structural systems. This includes describing a range of failure modes and response behaviors not commonly considered in protective design and the design/analysis approaches needed to address them. The goal here is to foment discussion toward establishing a more rational, robust, effective, and transparent design methodology.