Developing a Priority-Based Decision Making Method to Evaluate Geometric Configuration of Urban Interchanges

The present article involves in evaluation and engineering judgment of various geometric configurations for highway interchanges by considering substantial parameters over the discretion process. The geometric, economical and architectural criteria as the fundamental indicators are divided into related sub-indicators and the total combinations of such sub-elements from the general criterion for establishment of decision making process. Hence, this article deals with geometric configuration analysis of interchanges as a complex decision problem by the use of analytic hierarchy process (AHP) which is a structured technique to analyze complicated engineering systems. By considering an interchange as a case study in north of Tehran, the capital of Iran, the performance of the proposed method has been examined in order to  select the most suitable type of interchange by forming the evaluation process of AHP and taking into account the given design and construction data. In order to find a reasonable decision making approach for the optimum geometric configuration of highway interchange before construction stage, an interactive methodology has been reported in this study to facilitate the decision process, once a wide range of notorious criteria and desired prerequisites are available. Owing to established the AHP model and perform the decision-making method, the Expert Choice analytical software has been utilized. Only four options are considered for geometric shape of the interchange in the case study and the functionality of the process examined by reporting the general quantities for any option. The evaluation results are determined in terms of priorities for various options and their decision weights in the case study. However the presented model is able to be applied for other cases and different alternatives. As a tentative finding, using directional pattern for the case example of current work has been the optimum variant rather than parallel alternatives i.e. semi-directional and loop schemes.