A mechanistic approach for predicting the service life & performance of steel reinforced concrete bridge becks

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One of the significant problems facing the world today is the decay of infrastructure. The cost of protecting and restoring concrete structures worldwide is a large and growing problem (more than $100 billion in annual expenditures). A major component of this decay is the degradation of bridges and highways due to corrosion of the embedded reinforcing steel. This problem has prompted the development of a variety of alternative strategies for increasing the service life of reinforced concrete structures exposed to harsh environments. Among the most well known procedures, one can mention: chemical corrosion inhibitors, protective coatings on steel reinforcement, corrosion-resistant steels (stainless steels, MMFX, etc.), waterproofing membranes or sealants applied to the exposed surface of the concrete, cathodic protection, high performance concrete etc. Each of these alternative technologies has different technical merits and costs associated with their use. An optimum design/repair strategy requires not only an estimate of upfront costs, but also the means to compare all associated costs against the potential extension to the life of the structure. This issue is hardest to answer when considering newly developed materials (such as stainless steels, MMFX, and FRP composites) because of a lack of historical data about their field performance. In such situations, based on first principles, mechanistic approaches have proven to be very powerful tools for making reliable predictions under previously untested conditions. The main objective of the proposed research is to develop sound mechanistic models for reliable service life predictions using advanced theories and experimental techniques, including synchrotron-based testing methods. The presence of the Canadian Light Source (the national synchrotron facility: http://www.lightsource.ca) on the U of S campus provides the opportunity to conduct unprecedented high resolution microscopic analyses of materials. Synchrotron Light covers the full range of the light spectrum; allows greater accuracy and precision than has ever before been possible; and allows matter to be probed in real time under general environmental conditions (moisture, chemical reactions, etc.)