2019 CSCE Annual Conference - Laval (Greater Montreal) Conference
Dr. Ahmed Hammad, University of Alberta (Presenter)
Achieving sustainability is a major global challenge pressing on construction industry to reduce the pollution caused by its activities. Achieving sustainability requires changing the traditional cost/benefit analysis, which focuses only on financial gains, to a multicriteria decision-making model taking into consideration the three pillars of sustainability: economical, environmental and social aspects.
Construction waste is considered to be one of the main barriers towards achieving sustainability in construction. As per previous studies, concrete waste is the number one contributor to construction waste. This study is proposing a generic model to enable decision makers to select the most sustainable alternative to reduce concrete waste on construction sites.
The study starts with a comprehensive literature review regarding construction waste, Multi Criteria Decision Making (MCDM) techniques and their application to solve the construction waste problem. After that, Fuzzy Analytic Hierarchy Process (FAHP) technique is selected to minimize concrete waste. The developed model defined selection criteria and compared applicable alternatives to reduce concrete waste on construction sites with respect to the three aspects of sustainability: economical, environmental, and social using pairwise comparison matrices. Technical criteria has been also considered in the decision-making model. A case study has been conducted and several meetings have been held with various experts from the construction industry in United Arab Emirates. During these meetings, the experts defined selection criteria and agreed-upon weights to be assigned to the proposed criteria and applicable alternatives. Finally, the proposed model has been validated using the consistency test to eliminate inconsistency in the judgments of each pairwise comparison matrices as well as for the whole hierarchy. Results show that Concrete Prefabrication is the most sustainable alternative to solve this problem according to experts’ judgment.
The developed model defines the most important decision making criteria required to minimize concrete waste and introduces a new generic application to FAHP. The model can be implemented on any construction site and can be utilized by any group of expert decision-makers. Produced model results reflects experts’ preferences, increases awareness of sustainability measures and introduces a multicriteria consistent technique into the decision-making process.
Keywords: Construction Waste, Fuzzy Analytical Hierarchy Process, Multicriteria Decision-Making, Construction Waste Reduction.