Life Cycle Thinking–Based Decision Making for Bridges under Seismic Conditions. I: Methodology and Framework

Abstract

Bridges are an integral part of a country’s transportation infrastructure system. Earthquake-induced damages to bridges could result in fatalities and injuries, disturbances to the transportation infrastructure system, and incur significant repair costs. Furthermore, bridges must stay functional following an earthquake to maintain the continuity of transportation. Thus, innovative high-performance materials in the critical regions of structures and/or structural systems must be used located in regions of high seismic activity to mitigate the impacts of earthquakes. Despite having a higher seismic resilience, these structures, in general, tend to require a greater capital investment as a result of utilizing expensive material and special workmanship. However, when accounting for the postearthquake repair and maintenance costs, these seismically enhanced bridges can deliver significant cost advantages over conventional structures in the long run. Even so, the outcomes depend on the frequency and severity of the seismic damage, the lifespan of the bridge, the cost of materials, and the embodied emissions of the structures. To ensure better overall results, the cost–benefit analysis should be done with a life-cycle thinking perspective when comparing and making a decision related to multiple bridge systems. In this regard, a decision framework is developed to evaluate the overall life cycle performance of such a novel bridge, using fuzzy logic to integrate uncertainty. The proposed framework will assist engineers and the construction industry as a whole in making informed decisions regarding bridge infrastructure planning under dynamic conditions.