Quantitative Models for Life-Cycle Sustainability Cost of Concrete Bridge Structures

Abstract:

To quantitatively consider the environmental and social impacts of engineering structures at the planning and design stage， a comprehensive life-cycle sustainability cost framework and corresponding computational models are proposed. In terms of environmental impacts， the costs of preventing and controlling air， water， and soil pollutants are used as quantitative indicators， the environmental costs arising from engineering activities， traffic detours and congestion are modelled， and the environmental cost rates of common construction materials and fuels are summarized. In terms of social impacts， social cost calculation models are proposed， covering construction and traffic safety， passenger and freight transportation， regional economy， residential environment， and public services. The parameter values and calculation methods for life-cycle sustainability costs are illustrated with the comparison and selection of maintenance schemes for coastal bridges. For bridge maintenance schemes that occupy lanes， the sum of environmental and social costs far exceeds the direct economic costs， while maintenance schemes that do not occupy lanes have fewer environmental and social costs. Furthermore， among these maintenance schemes， the sustainability of the epoxy coating scheme is superior to that of the electrochemical chloride extraction scheme.

Key words:concrete bridge structures;sustainability;economic cost;environmental cost;social cost