The dependence on the physical infrastructure of roads, bridges, dams, water supply pipelines/aqueducts, ports and harbors, etc., is an integral part of our day-to-day life and so ingrained in our culture that we are mostly unaware of its existence as long as functionality is provided. The aging of our structures, natural hazards such as earthquakes, floods, and fires, as well as man-made disasters such as terrorist attacks and accidents, threaten the functionality of our physical infrastructure and extraordinary expenditures are required to just maintain the status quo. While advances will come in the form of new materials, new structural design and rehabilitation concepts and systems, the major breakthrough will come from a cyberinfrastructure coupled with our physical infrastructure, consisting of distributed multi-use sensor nets, wireless and high speed networks, fully searchable data bases, and modeling/performance simulations which provide the user with on-line infrastructure management tools.
From a structural engineering perspective, natural and man-made hazards, e.g. earthquakes and bomb blasts, can cause local structural damage, and in the absence of redundancy, progressive structural collapse. Research has shown that seismic design and retrofit concepts, e.g. confinement in columns, can go a long way to also harden structures against air blast loadings, and redundancy in a structural system can prevent progressive structural collapse for either load case. Thus, modern structural design needs to incorporate a multi-hazard risk assessment and hazard mitigation strategy based on a comprehensive performance assessment of the entire structural system’s response to all critical loads. To accomplish this, validated models and simulations of the performance of complex systems need to be developed, fully database-assisted to assess the most likely consequences of structural performance/non-performance. Validation of these simulation tools, in turn, requires large or full-scale structural testing that is representative of actual damage patterns and failure modes, as well as realistic loading patterns and rates.