| In recognizing dwindling resources, an ever-changing dynamic society and an environment which is increasingly being adversely affected by anthropogenic activities, civil engineering as a discipline has been moving steadily to anticipate what changes a future engineering climate would entail. The traditional way of assessing the characteristics of an engineering project solely based on cost and performance criteria is gradually being replaced by a paradigm centered on sustainable practices. Sustainability examines the whole continuum of a civil engineering project through the lenses of economics, society and the environment. By accepting this new paradigm, industry experts have helped raise the merits of sustainability from a level of awareness to the development of ratings that aid in assessment of sustainable initiatives. Though progress has been made in effectively disseminating the concept of sustainability to stakeholders, there still remain challenges as to how to move forward. Some of these challenges pertain to the exclusive use of qualitative assessments to analyze sustainable initiatives or the difficulty in translating strategic macro-level objectives into practical engineering actions at the micro-level as part of the infrastructure delivery process.;To counter some of these challenges, this research looks at how sustainability assessments can be improved by complementing the use of qualitative analysis with a more objective quantitative framework. With both qualitative and quantitative assessments, the asset management experience for civil infrastructure managers would be greatly enhanced. The research examines the current state of both qualitative and quantitative analyses, investigates their merits and demerits and recommends the use of a mathematical tool: viability theory which has been successfully applied to sustainability in fisheries and economic markets. Viability theory is based on a satisficing approach which recognizes that sustainability involves achieving multiple goals with value-laden constraints and provides the platform to assess multiple feasible solutions to achieve targets without focusing on a unique optimal solution path which may not meet the demands of sustainability. A case study using maintenance of an asphalt concrete pavement is presented. |
