Lead University: Lehigh University
PI: Dan M. Frangopol, Department of Civil and Environmental Engineering
PA Industry: ArcelorMittal

Steel and concrete bridges under aggressive environmental effects require frequent inspection, maintenance and repair activities to extend their service life and maintain an adequate performance level. In addition to the direct maintenance and inspection costs, these interventions may result in indirect costs associated with traffic delays and their economic, social, and environmental effects. These effects, if considered by using their monetary value, significantly affect the life-cycle cost of the bridge under consideration. Moreover, these deteriorating bridges become very vulnerable under extreme events (e.g., earthquakes and hurricanes). The use of more sustainable materials, such as maintenance-free steel, may increase the initial cost of the structure; however, the life-cycle cost, including maintenance, repair and inspection actions along the service life and their associated indirect effects, can be reduced. Therefore, an integrated approach is required to establish the optimum design alternative while considering life-cycle interventions. This project develops a sustainability-based framework to evaluate the life-cycle performance and cost of bridges. Emphasis will be placed on steel bridges which represent more than 30% of the bridges in Pennsylvania.

Outcomes of this project include (a) optimum choice of the bridge construction material based on he location in order to maximize sustainability, and (b) optimum intervention schedule to simultaneously maximize the service life and minimize the life-cycle cost considering traffic disruptions and thier associated impacts. Outcomes from this project are relevant to the management of the Nation's steel bridge infrastructure, and so should provide significant economic and social benefits to Pennsylvania. Companies such as ArcelorMittal will benefit from this project by using a life-cycle cost model that will clearly indicate the economic advantages of new solutions for steel bridges in terms of material and configuration which provide maintenance-free service during the whole bridge lifetime.