A life cycle perspective for infrastructure management.

Circular Economy, founded on the self-generative economic system concept, can be traced back to the theoretical approach of Life Cycle Thinking, that conceives the project as a process which develops along its whole life cycle, at the different scales: material, component, system, building, urban district and territorial area, infrastructure. In Italy, as in the main part of European Countries, a great portion of infrastructures was built in reinforced concrete before 1960 and is approaching the end-of-life stage, or has reached the end of its service life. Thus, aim of this article is to propose an operative modality for supporting the preventive maintenance investments planning in function of life cycle costs and benefits, assuming the presence of uncertainty over time. Focus is posed on the use-maintenance-adaptation stage in the infrastructures’ life cycle. The operative modality implies different cost/benefit amounts for maintenance-replacement interventions over time, including also society, owner, user and environmental costs. The work develops in three parts: firstly, a synthetic recalling of the “classic” Cost Benefit Analysis (CBA) approach is presented. Secondly, an introduction to the Life Cycle Cost Benefit Analysis (LCCBA) approach is proposed, as a tool for supporting long-term investments, management of public services and maintenance planning activities in the infrastructure sector (bridges, roads or highways). Thirdly, by integrating CBA and LCCBA, an operative modality is proposed focusing on the use-maintenance-adaptation phase in the construction life cycle. On the background, “life cycle management”, “optimal maintenance planning” and “durability” concepts are assumed. The methodological work opens some issues to address future researches: the possible shift from the Global Cost calculation to the Annuity Method, as a tool to resolve the LCCBA; the service life estimate and the maintenance time intervals definition, to guarantee construction durability; the control of uncertainty components in model input/output data and over time.