ARRA: Development of Functionally of Graded Protective Systems for Attenuation of Blast Loading

Abstract: This award is funded under the American recovery and Reinvestment Act of 2009 (Public Law 111-5) The aim of this project is to develop new structural architectures for resisting and mitigating the effects of impulsive loadings, such as blast and high velocity impacts, using functionally graded protective systems. The research approach combines theoretical concepts from wave propagation and nonlinear dynamics with a heuristic optimization methodology, based on genetic algorithms, to develop protective systems that have spatially varying stiffness, density and damping. In particular, this research will investigate functionally graded material systems, along with strategically allocated voids and solid or fluid inclusions for the objective of attenuating stress waves imparted on a structural system by blast and high velocity impacts. The first phase of the research will feature the use of numerical simulations, within a parallel grid computing environment, to develop novel functionally graded protective system concepts. A rigorous experimental investigation will then validate the effectiveness of the proposed functionally graded protective systems for mitigating impulsive loads and provide feedback for further enhancements of these protective systems. The impact of the project will occur at several levels. The research will lead to the generation of new knowledge associated with functionally graded materials and systems, along with the development of robust optimization tools that rely on coupling genetic algorithm methodology with finite element analysis to tailor material architectures for mitigating blast and high velocity impact loading. The validated functionally graded protective systems will enable engineers to apply these new design concepts in structural systems vulnerable to blast and high velocity impact environment. Finally, this has the potential to transform the present design philosophy for structural design under blast and high velocity impacts from one that emphasizes hardening to one focused on energy and momentum management. The project involves the education and mentoring of at least one doctoral student, the research findings will be incorporated into several graduate level courses, including one specifically on blast engineering and a web-based repository will be established to enable broad dissemination of the research results.