|M.Sc Student||Bassan Amir|
|Subject||Comparative Evaluation between a Conventional Diamond and|
Single-Point Urban Interchanges
|Department||Department of Civil and Environmental Engineering||Supervisor||Professor Abishai Polus|
This final paper is about the comparative evaluation between a conventional diamond and a single-point urban interchanges. The main objective of this research paper is to estimate, evaluate and compare the different characteristics between conventional diamond interchange and a single point urban interchange. A second objective is to estimate the capacity of the two interchanges, and compare the results with capacity values that have been accomplished by other researches. The data outcome has been used to develop models and create graphs in order to present and describe the traffic behavior in each type of interchange. Several scenarios of different traffic distributions have been examined in order to evaluate the capacity, the total delay and the level of service in each type of interchange. The models that were calibrated represent the equilibrium traffic volumes on the ramps vs. the traffic volumes in the crossroad street. The results have shown that there are particular volume ranges that justify the CDI alternative, whereas other ranges that justify the SPUI alternative. Those graphs are constructed for different volume scenarios and different cycle lengths between 50 and 150 seconds. The major findings indicate that the SPUI has higher capacity than the CDI, and is also superior as far as safety is concerned. A suitable design of the SPUI can decrease dramatically the traffic delays and traffic congestion mainly in high volumes. Furthermore, when the left turn traffic volumes in the crossroad exceeds 1000 vehicles\hour\lane, the SPUI functions more efficiently than the CDI.