| The conceptual establishment for sustainability in this research emphasizes concurrently enhancing environmental, economical and social aspects in urban infrastructure development. It is anticipated that this new concept, the enhancement of sustainability, is going to generate more long-term benefits without compromising the capability of future generations' prosperity. The development of a sustainability assessment model, through suggesting a new methodological assessment approach and decision making process, is the first step in integrating the complicated interrelations of sustainability issues that occur in real practice. The main objective of this research is to develop and implement a modeling framework for enhancing sustainability in urban underground infrastructure. The modeling framework in this research is named the Sustainability Assessment Model (SAM).; The SAM framework involves: (1) proposing alternatives; (2) identifying sustainability issues and indicators; (3) applying assessment methods; (4) integrating assessment results and prioritizing alternatives; and, (5) verifying the final decision. The SAM is designed to utilize multi-criteria decision making methods (MCDM), including AHP and WSM, and various quantitative estimation methods for cost, pollution, energy, time, and natural resource depletion as components of the modeling process.; In this study, the SAM is demonstrated and validated through a hypothetical case study for replacing an existing watermain system in the City of Scottsdale. Implementation of the SAM can effectively facilitate a project decision making process by simulating multiple scenarios, reflecting the various interests of potentially conflicting stakeholders. The most significant outcome of this research is the attempt at numerical expression and prioritization for future sustainability evaluation from present viewpoints. Application of the SAM may be premature in real world practice mainly because of the use of unreliable and inadequately defined data for future assessment. However, this study and the proposed SAM is surely a step forward in enhancing sustainability in infrastructure development by considering more sustainability issues and providing a more detailed framework than previous research. |
