Interchange ramp terminals are critical components of the highway network. They provide the connection between various highway facilities (e.g., freeway–arterial and arterial–arterial), and their safe and efficient operation is essential. The objective of this research was to develop improved methods for capacity and quality-of-service analysis of interchange ramp terminals. The research focuses on at-grade intersections but not on the freeway proper. All geometric configurations and interchange types except trumpet interchanges are considered, and the scope of the research includes only signalized interchanges and not “Stop” sign–controlled interchanges and roundabouts. The development of the analytical methodology is primarily based on simulation. The reason for using simulation is that adequate samples of field data are not available, and it is prohibitively expensive to collect them for all types of interchange configurations. The research team assessed several simulation models that were identified as capable of simulating all types of interchange ramp terminals and selected the most appropriate one for model development. Once a simulation model was selected, a variety of interchange configurations were simulated, and selected measures of effectiveness were obtained. Analytical models were developed on the basis of the results of simulation to predict different measures, such as average control delay, volume-to-capacity ratio, and queue-to-storage ratio, for a variety of design and traffic control characteristics.

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Fang (Clara) Fang, University of HartfordDr. Fang Clara Fang is an Assistant Professor at the University of Hartford, where she teaches both undergraduate and graduate courses, and conducts research in transportation engineering. She received a Ph.D. degree from the Pennsylvania State University and MS from the University of British Columbia. She is the author or co-author of more than dozen of refereed Journals, conferences and reports. Her research interests include computer modeling and simulation of transportation systems, traffic signal control, and the application of advanced mathematical and operation research knowledge including optimization methods, artificial intelligence, and stochastic process in transportation engineering.

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This research is dedicated to the study of dynamics of vehicles moving through the additional entry lanes of a roundabout. Using the data created on the base of that model the constant coefficients of the sixth-degree polynomial function, previously proposed by us, have been found. In result of this there were obtained two analytic equations of vehicles' movement, where one of them presented with the positive sign of the leading coefficient and the other one negative. These two equations allowed to make comprehensive investigation of the delays and the kinematics of the vehicles moving by such kinds of lanes. Based on the appropriate calculations it is determined vehicles' consequent delays, velocities, accelerations and decelerations. Analyzing the delays, the dynamics of accelerations and decelerations, it is done an assumption that if the leading coefficient of algorithm of movement of vehicles is negative than it will lead to larger deceleration and consequently higher environmental pollutions and higher noises.