A hybrid contractor selection approach with analytical hierarchy process (AHP) and VIKOR method in public building auctions

Contractor selection is an important factor in order for construction projects to be completed within the foreseeable budget and time and within the required quality specifications. After certain conditions are met in public tenders in Turkey, the bids given by the contractor companies are subject to the limit value account. As a result of this account, the company that made the lowest bid economically is considered to have won the tender. But looking at the lowest bid criteria in selecting a contractor can lead to problems over time. In fact, determining the contractor of a construction tender is the nature of many criteria decision-making problems that require the optimization of many criteria separately. For this reason, the use of solution approaches based on multiple criteria will provide more qualified results in the selection of contractors. In this study, an alternative approach to the approach applied in existing public tenders was proposed. A model has been proposed in which some of the pre-qualification or qualification requirements are included, but also added to other criteria. The proposed model is a Multi-Criteria Decision-Making (CCC) hybrid approach to selecting the most suitable one among the candidates participating in the public construction tender. In this approach, the analytical hierarchy process (AHP) and the VIKOR method were applied together. AHP method was used to determine the weights of the criteria and VIKOR method was used to reflect many criteria to the solution. For the study, a wide-ranging literature review was conducted and determined the main and sub-criteria. Ratings of the criteria determined were interviewed and conducted with experts on public construction tenders. First, contractor selection was made using the AHP method. After that, the choice of contractor was made by the VIKOR method. Finally, the AHP-VIKOR hybrid solution was made with the weights of the criteria obtained by the AHP method in order to realize the rankings made using both methods individually with a healthier approach. In this way, if the criteria to be minimized and maximized contradict each other, the VIKOR method, which is a successful approach to achieving an optimal solution, was hybrid with the AHP method and an even more appropriate choice was made for the purpose. As a result of the study, the rankings obtained with all three approaches were compared. In this way, it has been concluded that if the company that will win the tender in the tender system is decided in this alternative way, healthier solutions can be achieved than in its current state.