Structural Identification of Various Constructed Systems to Inform Decisions

With the recent collapse of the I-35 Bridge in Minneapolis, MN, the societal challenges associated with our nation's aging infrastructures were thrust to the forefront. Throughout the recent election season, infrastructure issues, for the first time in recent memory, were mentioned alongside perennial political discussions related to health care and education. These discussions and the issues associated with infrastructure preservation and renewal have resonated at both the local/state and national levels. For example, Governors Edward Rendell and Arnold Schwarzenegger along with Mayor Michael Bloomberg formed a non-partisan coalition, backed by the Rockefeller Foundation, aimed at making infrastructure funding a national priority. In addition, in early December of 2008, President-elect Barack Obama indicated his administration would make the single largest investment into the U.S. infrastructure since the 1950s, when the interstate system was developed. While the call for increased infrastructure funding is welcomed by owners; the reality is that current civil engineering practices may not be capable of effectively leveraging such funds for preservation and renewal. The traditional practice of using conservatism in the face of uncertainty serves new design well, but provides owners with a poor picture of reality and has fueled record budget shortfalls. This challenge demands approaches capable of establishing accurate estimates of infrastructure vulnerability and risk to facilitate rational and informed decisions. Over the last decade the Drexel Intelligent Infrastructure Institute (DI3) has served numerous infrastructure owners through the use of structural identification (St-Id) to more reliably assess structural vulnerability and risk as they meet this challenge. The objective of this paper is to outline some of these experiences with a particular focus on the perspective of the decision-maker. The paper begins with an overview of St-Id, which is followed by a summary of the types of applications DI3 has been involved in. The relationship between St-Id applications and risk-based decision making is then discussed and the paper is concluded with a summary of the challenges related to using St-Id to support infrastructure decision-making.