Sustainability Metrics for Performance-Based Seismic Bridge Response

Abstract

Previous performance-based earthquake engineering investigations on highway bridges focused on repair cost and repair time metrics. These are primarily related to economic life-cycle cost analysis decision-making strategies for evaluating the vulnerability of bridges. However, environmental impacts considered during life-cycle assessment are also of interest. A methodology for quantifying the sustainability of bridge designs using carbon footprint as the performance metric is presented. Point estimates of the carbon footprint, repair cost, and repair time are used to compute resilience of several bridge-ground scenarios. Several multispan reinforced concrete highway overpass bridges in California from previous studies were selected for study because post-earthquake probabilistic repair cost and time data are already available. It is demonstrated that the disaggregation of the structure into performance groups, or components that are repaired together, and the probabilistic methodology previously employed lend themselves to the additional computations for carbon footprint. The performance groups and material quantities that drive the major contributions to carbon footprint as opposed to economic costs are presented.